La gran cantidad de adhesivos en el comercio, su importancia en la retención y la filtración de las obturaciones de resina compuesta, asi como su diversidad, avalan la publicación de este tema.
Hasta hoy, dos tipos de adhesivos se presentan en el comercio: Los de un sólo envase (Ej. Single Bond 2) y aquellos que se denominan “autograbantes”. La literatura es un poco dispersa y no he incluído aquí la que dice relación con Ortodoncia, salvo excepciones.
He conservado el viejo cuadro de adhesivos publicado por CRA hace ya varios años sólo como ilustración.
Dr. Jorge Garat.
J Prosthodont. 2010 Feb 25. [Epub ahead of print]
Bonding to Zirconia Using a New Surface Treatment.
Aboushelib MN, Feilzer AJ, Kleverlaan CJ.
Dental Biomaterials Department, Faculty of Dentistry, Alexandria University, Egypt.
Abstract Purpose: Selective infiltration etching (SIE) is a newly developed surface treatment used to modify the surface of zirconia-based materials, rendering them ready for bonding to resin cements. The aim of this study was to evaluate the zirconia/resin bond strength and durability using the proposed technique. Materials and Methods: Fifty-four zirconia discs were fabricated and divided into three groups (n = 18) according to their surface treatment: as-sintered surface (control group), airborne-particle abrasion (50-mum aluminum oxide), and SIE group. The zirconia discs were bonded to preaged composite resin discs using a light-polymerized adhesive resin (Panavia F 2.0). The zirconia/resin bond strength was evaluated using microtensile bond strength test (MTBS), and the test was repeated after each of the following intervals of accelerated artificial aging (AA): thermocycling (10,000 cycles between 5 and 55 degrees C), 4 weeks of water storage (37 degrees C), and finally 26 weeks of water storage (37 degrees C). Silver nitrate nanoleakage analysis was used to assess the quality of zirconia/resin interface. A repeated measures ANOVA and Bonferroni post hoc test were used to analyze the data (n = 18, alpha= 0.05) Results: There were significant differences in the MTBS values between the three test groups at each of the test intervals (p < 0.001). AA resulted in reduction in the bond strength of the as-sintered and the particle-abraded groups (5.9 MPa and 27.4, MPa, respectively). Reduction in the bond strength of these groups was explained by the observed nanoleakage across the zirconia/resin interface. The bond strength of the SIE specimens was stable after completion of AA (51.9 MPa), which also demonstrated a good seal against silver nitrate penetration across the zirconia/resin interface. Conclusion: SIE established a strong, stable, and durable bond to zirconia substrates. Conservative resin-bonded zirconia restorations are now possible using this new technique.
Acta Odontol Scand. 2010 Mar 3. [Epub ahead of print]
Bond strength of a self-adhesive resinous cement to root dentin irradiated with a 980-nm diode laser.
Garcia LD, Naves LZ, Correr-Sobrinho L, Consani S, Pires-De-Souza FD.
Department of Restorative Dentistry, Dental Materials Area, Piracicaba School of Dentistry, Campinas State University, Piracicaba, São Paulo, Brazil.
Abstract Objective. To assess the bond strength of Rely-X Unicem (RX), in comparison with Cement-Post (CP), to the cervical, middle and apical thirds of root canal dentin irradiated with a 980-nm diode laser. Material and methods. Forty maxillary canines were separated into four equal groups according to the cement used and the laser surface treatment: RX/laser irradiation (LI) group; RX/no irradiation (NI) group; CP/LI group; and CP/NI group. Two slices (2-mm thick) of each root third were submitted to a push-out test to assess the bond strength of the cement to the root canal dentin. The data obtained were submitted to two-way ANOVA and fracture analysis was performed by scanning electron microscopy. Results. The type of cement as well as 980-nm LI at the different root canal thirds significantly affected the bond strength values (p < 0.05). LI promoted an increase in bond strength of RX in all root thirds (p < 0.05). For all groups, bond strength to the cervical third was highest, followed by the middle and apical thirds (p < 0.05). When the cements were compared, RX always presented the highest bond strength in comparison with CP, irrespective of the laser application (p < 0.05). Fracture analysis showed a predominance of mixed failures for RX and of adhesive failure between dentin and cement for CP, irrespective of the laser application. Conclusion. The 980-nm LI promoted an increase in bond strength of the self-adhesive resinous cement to root dentin.
Dent Mater. 2010 Feb 25. [Epub ahead of print]
Dental adhesives with bioactive and on-demand bactericidal properties.
Welch K, Cai Y, Engqvist H, Strømme M.
Nanotechnology and Functional Materials, The Angström Laboratory, Uppsala University, Uppsala, Sweden.
OBJECTIVES: The aim of the present work was to perform the first in vitro evaluation of a new interfacial bond-promoting material-and-method concept for on-demand long term bacteria inhibition in dental restoration procedures. METHODS: The bioactivity, mechanical bonding strength and photocatalytic bactericidal properties, induced by low dose ultraviolet-A (UV-A) irradiation of dental adhesives containing crystalline titania nanoparticles (NPs), were analyzed. RESULTS: Dental adhesives with a NP content of 20wt% were shown to be bioactive in terms of spontaneous hydroxylapatite formation upon storage in simulated body fluid and the bioactivity was found to be promoted by chemical etching of the adhesives. The mechanical bonding strength between the adhesives and a HA tooth model was shown to be unaffected by the NPs up to a NP content of 30wt%. Elimination of Staphylococcus epidermidis in contact with the adhesives was found to depend both on UV photocatalytic irradiation intensity and time. Efficient elimination of the bacteria could be achieved using a UV-A dose of 4.5J/cm(2) which is about 6 times below the safe maximum UV dose according to industry guidelines, and 20 times below the average UV-A dose received during an ordinary sun bed session. SIGNIFICANCE: The combined features of bioactivity and on-demand bactericidal effect should open up the potential to create dental adhesives that reduce the incidence of secondary caries and promote closure of gaps forming at the interface towards the tooth via remineralization of adjacent tooth substance, as well as prevention of bacterial infections via on-demand UV-A irradiation. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Am J Dent. 2009 Dec;22(6):371-5.
Enamel-resin bond durability of self-etch and etch & rinse adhesives.
Osorio R, Monticelli F, Moreira MA, Osorio E, Toledano M.
Department of Dental Materials, Dental School, University of Granada, Colegio Máximo, Campus de Cartuja s/n 18017 Granada, Spain.
PURPOSE: To evaluate the degradation of resin-enamel interfaces bonded with different adhesive systems. METHODS: Flat enamel surfaces were ground buccally on bovine incisors. Two etch & rinse self-priming adhesives (Single Bond, Prime & Bond NT), three two-step self-etch adhesives (Clearfil SE Bond, Resulcin Aquaprime, NRC/Prime & Bond NT) and two all-in-one adhesives (Etch & Prime 3.0, Adper Prompt-L-Pop) were used for bonding. A hybrid resin composite (Tetric Ceram) was selected for coronal build-up. Bonded specimens were stored in water at 37 degrees C for 24 hours, 6 months and 1 year, respectively, and then sectioned into 1 mm2 beams. Each microtensile stick was loaded in tension until failure (crosshead speed: 0.5 mm/minute). Bond strength data were analyzed with two-way ANOVA and Student Newman Keuls tests (P < 0.05). Etching patterns resulting from phosphoric acid etching and self-etch adhesives application on ground enamel were analyzed under SEM. RESULTS: All adhesives attained similar bond strengths after 24 hours. All-in-one adhesives and Resulcin Aqua Prime recorded a significant reduction in bond strengths after 6 months and 1 year of water aging.
Oper Dent. 2010 Jan-Feb;35(1):77-83.
Influence of adhesive application time on enamel bond strength of single-step self-etch adhesive systems.
Tsuchiya H, Tsubota K, Iwasa M, Ando S, Miyazaki M, Platt JA.
Nihon University School of Dentistry, Department of Operative Dentistry, Tokyo, Japan.
This study examined the relationship between the adhesive application time and enamel bond strength of several single-step self-etch adhesive systems. The adhesives used were: Bond Force (BF, Tokuyama Dental Corporation, Tokyo, Japan), Clearfil tri-S Bond (CT, Kuraray Medical Inc, Tokyo, Japan), iBond Self-Etch (IB, Heraeus Kulzer, Armonk, NY) and OptiBond All-in-One (OB, sds Kerr). Bovine mandibular incisors were mounted in self-curing resin and wet ground with #600-grit silicon carbide paper to expose labial enamel. Adhesives were applied for 10, 20 or 40 seconds and the resin composites were condensed into a mold (phi4 x 2 mm) on the enamel and light irradiated. Ten samples per test group were stored in 37 degrees C water for 24 hours, then shear tested at a crosshead speed of 1.0 mm/minute. One-way ANOVA and the Tukey HSD test (alpha = 0.05) were performed within each adhesive system. The enamel surfaces after adhesive application were also observed in a Field Emission Electron Probe Surface Roughness Analyzer and the Ra value was calculated. The enamel bond strength ranged from 13.6 to 17.8 MPa for BF, 13.6 to 15.9 MPa for CT, 14.3 to 16.2 MPa for IB and 13.4 to 19.8 MPa for OB. Significant increases in bond strength were found for the 40-second application groups, except for IB. No changes in Ra value were found for BF and IB, while significant decreases in Ra value were recorded with 40-second application for CT and OB. The data suggested that the duration of the single-step self-etch adhesive application was a crucial factor for determining the enamel bond strengths of some of the single-step self-etch adhesives employed in the current study.
Oper Dent. 2010 Jan-Feb;35(1):69-76.
Evaluation of bond strength and internal adaptation between the dental cavity and adhesives applied in one and two layers.
Soares CG, Carracho HG, Braun AP, Borges GA, Hirakata LM, Spohr AM.
Operative Dentistry, Pontifical Catholic University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
This research evaluated the influence of the number of adhesive layers of three adhesive systems on microtensile bond strength (microTBS) to dentin and the internal adaptation between the dental structure and the resin composite restoration. Two cavities (C-factor = 3) were made on the buccal surfaces of 30 bovine incisors. Scotchbond Multi-Purpose (MP), Adper Single Bond 2 (SB) and Clearfil SE Bond (CSB) were applied in one layer (MP-I, SB-I and CSB-I) and in two layers (MP-II, SB-II and CSB-II). The cavities were restored with Z250 resin composite. After 48 hours, beams were obtained (n = 15/group) for microTBS testing, and slices containing the two restorations were obtained for internal adaptation analysis. The beams were submitted to the microTBS test on a universal testing machine (EMIC DL-2000) and the failures were analyzed by SEM. The slices were analyzed under an optical microscope and the types and amounts of internal failures (gap, crack, rupture) were classified. The mean values of microTBS (MPa) were: MP-II: 56.92; MP-I: 52:23; CSB-II: 47:71; CSB-I: 42.25; SB-I: 35.12 and SB-II: 34.69. According to two-way ANOVA (alpha = 0.05), the independent variables adhesive system (p = 0.001) and the number of layers (p = 0.025) presented significant difference. The mixed failure was predominant in all groups. For the internal adaptation analysis, the Kruskal-Wallis test (alpha = 0.05) showed statistical differences for cracks and ruptures between the adhesive systems. SB-I and II were shown to have the highest values for cracks, and MP-I demonstrated the lowest. SB-II showed significantly higher values for rupture. The application of two layers promoted a slight increase in microTBS for Scotchbond MP and Clearfil SE Bond, but it did not improve the internal adaptation for the tested adhesive systems.
Swed Dent J. 2009;33(4):193-9.
One year clinical performance and post-operative sensitivity of a bioactive dental luting cement–a prospective clinical study.
Jefferies SR, Pameijer CH, Appleby D, Boston D, Lööf J, Glantz PO.
Kornberg School of Dentistry, Temple University, Philadelphia, USA.
A one-year clinical study was performed on the efficacy of a bioactive dental cement (Ceramir C&B) with calcium aluminate and glass ionomer components. The study was performed on 38 crown and bridge abutments in 17 patients. Preparation parameters were recorded, as well as working-times, setting-times, and other handling characteristics. Baseline data were also recorded for gingival inflammation (GI) and pre-cementation sensitivity. Post-cementation parameters included sensitivity, gingival tissue reactions, marginal integrity and discolorations. All patients were seen for recall examinations at 30 days, and 6 months. For sixteen patients one-year recall data were collected on retention and subjective sensitivity. Fifteen subjects were available for one year clinical examinations. Three independent examiners found the working and setting time of the cement to be well within expected limits and that cement removal was easy. Four patients reported low-grades of immediate post-cementation sensitivity, however, this disappeared after an occlusal adjustment or without intervention within one month. At 12 months no retentive failures were recorded and no subjective sensitivity reported. All crowns were rated in the “Excellent” quality category for marginal integrity. Both GI-scores and scores for tooth sensitivity decreased during the course of the study. One year recall data yielded no incidence of secondary caries and no visible marginal discoloration. The new cement was thus found to perform favorably as a luting agent for permanent cementation.
Dent Mater. 2010 Jan 24. [Epub ahead of print]
Effect of primer treatment on bonding of resin cements to zirconia ceramic.
Kitayama S, Nikaido T, Takahashi R, Zhu L, Ikeda M, Foxton RM, Sadr A, Tagami J.
Cariology and Operative Dentistry, Department of Restorative Science, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan; Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Diseases at Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan.
OBJECTIVES: To evaluate and compare bond strengths of different primers and resin cements to silica-based and zirconia ceramics. METHODS: Silica-based and zirconia ceramic specimens were ground flat with #600-grit SiC paper. The ceramic surfaces were airborne-particle abraded and then divided into 11 groups of seven each: untreated (control); and conditioned with one of the six primers in combination with a resin cement from the same manufacturer as follows: Bistite II/Tokuso Ceramic Primer, Linkmax/GC Ceramic Primer, RelyX ARC/RelyX Ceramic Primer, Panavia F 2.0/Clearfil Ceramic Primer, and Resicem/Shofu Porcelain Primer and Resicem/AZ Primer. Stainless steel rods were bonded to the ceramic surfaces using one of the five resin cements. After 24-h water storage, the tensile bond strengths were tested using a universal testing machine and failure modes were examined. RESULTS: Conditioning with primers containing a silane coupling agent (all the primers except AZ Primer) significantly enhanced bond strengths of resin cements to silica-based ceramic. For zirconia ceramic, Resicem/AZ Primer exhibited significantly higher bond strength than the other groups except Panavia F 2.0/Clearfil Ceramic Primer. The predominant failure mode of the groups conditioned with primers containing a phosphonic acid monomer (AZ Primer) or a phosphate ester monomer (Clearfil Ceramic Primer and Tokuso Ceramic Primer) was cohesive failure in cements whereas that with the other primers was adhesive failure at the zirconia surfaces. SIGNIFICANCE: The use of primers containing a silane coupling agent improved resin bonding to silica-based ceramic. On the other hand, the use of primers containing a phosphonic acid monomer or a phosphate ester monomer improved resin bonding to zirconia ceramic. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
New Microbiol. 2009 Oct;32(4):385-90.
In vitro evaluation of the antibacterial activity of cured dentin/enamel adhesive incorporating the antimicrobial agent MDPB.
Giammanco GM, Cumbo EM, Luciani A, Gallina G, Mammina C, Pizzo G.
Department of Health Promotion Sciences, University of Palermo, Italy. g.m.giammanco@unipa.it
The aim of this study was to investigate in vitro the antibacterial effect of a dentin/enamel adhesive containing MDPB (Clearfil Protect Bond) after curing and to compare it with an adhesive not containing MDPB (Clearfil SE Bond). The antibacterial effect of the cured adhesives was tested on Enterococcus faecalis by the evaluation of growth inhibition in a 48-h microplate direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by an agar diffusion test (ADT) performed with the adhesives cured on the surface of dentin disks. In the DCT, both the tested materials showed complete inhibition of bacterial growth until the 7-h reading, regardless of whether direct contact with the bacterial inoculum was continued or limited to 1 h. Stationary growth phase turbidity levels were observed at 24 or 48-h incubation. The ADT produced no inhibition areas around the dentin disks. Both adhesives tested in vitro under conditions simulating those encountered in the restorative treatment of dental caries were equally able to delay bacterial growth demonstrating a similar bacteriostatic effect. As suggested by both the DCT and the ADT, the antibacterial effect of the two adhesives depends on direct contact and does not seem to be related to the diffusion of soluble components.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2009 Oct;44(10):621-5.
[Antibacterial effects of a dental adhesive incorporating a quaternary ammonium monomer against Streptococcus mutans]
[Article in Chinese]
Li F, Chen JH, Ma S, Zhang L, Xiao YH, Fang M.
Department of Prosthodontics, The Fourth Military Medical University, Xi’an 710032, China.
OBJECTIVE: To incorporate an antibacterial monomer, methacryloxylethyl cetyl dimethyl ammonium chloride(DMAE-CB), into a dental adhesive, and to evaluate the antibacterial activity against Streptococcus mutans (Sm) of this DMAE-CB-incorporated adhesive after being cured. METHODS: DMAE-CB was incorporated into a dimethacrylates-based dental adhesive as experimental group. The adhesive without DMAE-CB served as a negative control. Thirty-nine specimens were fabricated for each group. The effects of the cured adhesives on the growth and adherence of Sm were evaluated with growth inhibition assay and spectrophotometry respectively. The influence of aging treatment and saliva treatment on the antibacterial efficiency of the modified adhesive was evaluated. Moreover, the bacterial growth of Sm in the eluents of two different adhesives was examined. RESULTS: Compared with negative control, the cured DMAE-CB-incorporated dental adhesive exhibited inhibitory effect on the growth and adherence of Sm. The inhibition rate was 99% and the absorbance value was (0.332 +/- 0.063) for experimental group, significantly lower than that of negative control (0.434 +/- 0.093, P = 0.021). Moreover, after aging treatment the DMAE-CB-incorporated adhesive could still inhibit the growth and adherence of Sm; the inhibition rate was 99%, and the absorbance value of experimental group was (0.372 +/- 0.062), significantly lower than that of negative control (0.455 +/- 0.066, P = 0.022). After saliva treatment the DMAE-CB-incorporated adhesive could still inhibit the growth and adherence of Sm; the inhibition rate was 90%, and the absorbance value of experimental group was (0.299 +/- 0.061), significantly lower than that of negative control (0.370 +/- 0.068, P = 0.045). However, the eluent of DMAE-CB-incorporated adhesive didn’t show inhibitory effect on the growth of Sm when compared with negative control, and the antibacterial effect and the doubling time of experimental group [(130.5 +/- 8.4) min] had no statistical difference than negative control [(126.4 +/- 7.0) min, P = 0.298]. CONCLUSIONS: The incorporation of DMAE-CB can render the dental adhesive with antibacterial activity after polymerization via influencing the growth and adherence of Sm.
J Appl Oral Sci. 2009 Nov-Dec;17(6):544-54.
Cytotoxicity and biocompatibility of direct and indirect pulp capping materials.
Modena KC, Casas-Apayco LC, Atta MT, Costa CA, Hebling J, Sipert CR, Navarro MF, Santos CF.
Department of Operative Dentistry, Endodontics and Dental Materials, University of São Paulo, Bauru, Brazil.
There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH), adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH.
Dent Mater J. 2009 Nov;28(6):743-9.
Dentin bond strength of a new adhesive system containing calcium phosphate experimentally developed for direct pulp capping.
Shinkai K, Taira Y, Suzuki M, Kato C, Ebihara T, Wakaki S, Seki H, Shirono M, Ogisu T, Yamauchi J, Suzuki S, Katoh Y.
Department of Operative Dentistry, School of Life Dentistry at Niigata, The Nippon Dental University.
The purpose of this study was to evaluate the microtensile bond strength (muTBS) to human dentin of an experimental bonding agent containing calcium phosphates experimentally developed for direct pulp capping. Different concentrations of four types of calcium phosphates were added to an experimental bonding monomer, and six experimental bonding agents were thus prepared. Clearfil SE Bond/Bond was used as the control. Flat dentin surfaces of human molars were assigned to the experimental adhesive systems and the control. After Clearfil SE Bond/Primer was applied to the dentin surface, each experimental bonding agent was applied and photopolymerized, and then a resin composite paste was placed and photopolymerized. The specimens were subjected to muTBS testing. Results revealed that there were no significant differences among the muTBS values of the experimental bonding agents and the control. In other words, the calcium phosphate-containing experimental adhesives did not adversely affect the muTBS to dentin.
Dent Mater.. [Epub ahead of print]
Dentin bonding-Variables related to the clinical situation and the substrate treatment.
Department of Restorative Sciences, Division of Operative Dentistry, University of Minnesota School of Dentistry, 515 SE Delaware St., 8-450 Moos Tower, Minneapolis, MN 55455, USA.
The wetness of dentin surfaces, the presence of pulpal pressure, and the thickness of dentin are extremely important variables during bonding procedures, especially when testing bond strength of adhesive materials in vitro with the intention of simulating in vivo conditions. The ultimate goal of a bonded restoration is to attain an intimate adaptation of the restorative material with the dental substrate. This task is difficult to achieve as the bonding process is different for enamel and for dentin-dentin is more humid and more organic than enamel. While enamel is predominantly mineral, dentin contains a significant amount of water and organic material, mainly type I collagen. This humid and organic nature of dentin makes this hard tissue very challenging to bond to. Several other substrate-related variables may affect the clinical outcome of bonded restorations. Bonding to caries-affected dentin is hampered by its lower hardness and presence of mineral deposits in the tubules. Non-carious cervical areas contain hypermineralized dentin and denatured collagen, which is not the ideal combination for a bonding substrate. Physiological transparent root dentin forms without trauma or caries lesion as a natural part of aging. Similar to the transparent dentin observed underneath caries lesions, the tubule lumina become filled with mineral from passive chemical precipitation, making resin hybridization difficult. An increase in number of tubules with depth and, consequently, increase in dentin wetness, make bonding to deeper dentin more difficult than to superficial dentin. While the application of acidic agents open the pathway for the diffusion of monomers into the collagen network, it also facilitates the outward seepage of tubular fluid from the pulp to the dentin surface, deteriorating the bonding for some of the current adhesives. Some dentin desensitizers have shown some promise as they can block dentinal tubules to treat and prevent sensitivity and simultaneously blocking the tubular fluid from flowing to the surface. A new approach to stop the degradation of dentin-resin interfaces is the use of MMP inhibitors. Although still in an early phase of in vitro and clinical research, this method is promising.
Dent Mater.. [Epub ahead of print]
Adhesion to tooth structure: A critical review of “macro” test methods.
Braga RR, Meira JB, Boaro LC, Xavier TA.
University of São Paulo School of Dentistry, Dept. of Dental Materials, Av. Prof. Lineu Prestes, 2227, São Paulo, SP 05508-000, Brazil.
OBJECTIVES: Bond strength between adhesive systems and the tooth structure is influenced by a large number of variables, which makes the comparison among studies virtually impossible. Also, failure often times propagates into the dental substrate or the composite, deeming the results questionable at best. In spite of the increased popularity gained by micro-tensile and micro-shear tests, in vitro evaluations using specimens with relatively large bonding areas remain frequent. This review focuses on aspects related to specimen geometry and test mechanics of “macro” shear and tensile bond strength tests. METHODS: Besides information drawn from the literature, the effect of some parameters on stress distribution at the bonded interface was assessed using finite element analysis (FEA). RESULTS: Bond strength tends to increase with smaller bonding areas and with the use of high elastic modulus composites. Stress concentration at the bonded interface is much more severe in shear compared to tension. Among shear methods, the use of the chisel shows the highest stress concentration. Within the limits suggested by the ISO/TS 11405, crosshead speed does not seem to influence bond strength values. Pooled data from currently available adhesives tested in either shear or tension showed 44% of adhesive failures, 31% mixed and 25% cohesive in the substrate (tooth or composite). A comparative bond strength study involving three adhesive systems revealed similarities between “macro” and “micro” counterparts regarding material ranking, whereas “macro” tests presented a higher incidence of cohesive failures. SIGNIFICANCE: Simplicity warrants “macro” bond strength tests an enduring popularity, in spite of their evident limitations. From a mechanical standpoint, knowing the stress distribution at the bonded interface and how it is affected by the materials and loading method used is key to explain the results.
J Dent. 2009 Dec 6. [Epub ahead of print]
Six-month evaluation of adhesives interface created by a hydrophobic adhesive to acid-etched ethanol-wet bonded dentine with simplified dehydration protocols.
Sadek FT, Mazzoni A, Breschi L, Tay FR, Braga RR.
Department of Dental Materials, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes, 2227, São Paulo, SP, Brazil.
OBJECTIVES: To evaluate the efficacy of simplified dehydration protocols, in the absence of tubular occlusion, on bond strength and interfacial nanoleakage of a hydrophobic experimental adhesive blend to acid-etched, ethanol-dehydrated dentine immediately and after 6 months. METHODS: Molars were randomly assigned to 6 treatment groups (n=5). Under pulpal pressure simulation, dentine crowns were acid-etched with 35% H(3)PO(4) and rinsed with water. Adper Scotchbond Multi-Purpose was used for the control group. The remaining groups had their dentine surface dehydrated with ethanol solutions: group 1=50%, 70%, 80%, 95% and 3×100%, 30s for each application; group 2 the same ethanol sequence with 15s for each solution; groups 3, 4 and 5 used 100% ethanol only, applied in seven, three or one 30s step, respectively. After dehydration, a primer (50% BisGMA+TEGDMA, 50% ethanol) was used, followed by the neat comonomer adhesive application. Resin composite build-ups were then prepared using an incremental technique. Specimens were stored for 24h, sectioned into beams and stressed to failure after 24h or after 6 months of artificial ageing. Interfacial silver leakage evaluation was performed for both storage periods (n=5 per subgroup). RESULTS: Group 1 showed higher bond strengths at 24h or after 6 months of ageing (45.6+/-5.9(a)/43.1+/-3.2(a)MPa) and lower silver impregnation. Bond strength results were statistically similar to control group (41.2+/-3.3(ab)/38.3+/-4.0(ab)MPa), group 2 (40.0+/-3.1(ab)/38.6+/-3.2(ab)MPa), and group 3 at 24h (35.5+/-4.3(ab)MPa). Groups 4 (34.6+/-5.7(bc)/25.9+/-4.1(c)MPa) and 5 (24.7+/-4.9(c)/18.2+/-4.2(c)MPa) resulted in lower bond strengths, extensive interfacial nanoleakage and more prominent reductions (up to 25%) in bond strengths after 6 months of ageing. CONCLUSIONS: Simplified dehydration protocols using one or three 100% ethanol applications should be avoided for the ethanol-wet bonding technique in the absence of tubular occlusion, as they showed decreased bond strength, more severe nanoleakage and reduced bond stability over time.
J Prosthet Dent. 2009 Dec;102(6):368-77.
Effect of surface conditioning on the retentive bond strengths of fiberreinforced composite posts.
Schmage P, Cakir FY, Nergiz I, Pfeiffer P.
Department of Restorative and Preventive Dentistry, School of Dental and Oral Medicine, University of Hamburg, Hamburg, Germany.
STATEMENT OF PROBLEM: Debonding is a common cause of failure encountered with fiber-reinforced composite (FRC) posts, and usually occurs along the post space-dentin adhesive interface. Surface conditioning of posts is expected to increase the chemical and mechanical bond between the luting composite resin and the post, but the best method has not been definitively determined. PURPOSE: The purpose of this in vitro study was to compare the effects of 3 surface-conditioning methods on the retentive bond strengths of FRC posts using 5 composite resin materials, and compare results to those of unconditioned FRC posts as well. MATERIAL AND METHODS: Post space preparations (DentinPost ER root post system, length of 12 mm) were performed on 200 human anterior teeth. Groups of 50 FRC posts (ISO size 90) each were treated using 1 of the following conditioning methods: silanization, etching with 5% hydrofluoric acid, tribochemical coating (CoJet system), or were left untreated (control group). FRC posts (n=10) in each group were placed using 1 of 5 composite resin materials (Calibra or RelyX Unicem resin cements or Build-It, MultiCore Flow, or Rebilda DC foundation composite resins). Following water storage (37 degrees C, 24 hours) and thermal cycling (5000 cycles, 5 degrees -55 degrees C, 30-second dwell time), tensile strength testing was performed. Fracture modes were assessed using a light microscope. Data were analyzed statistically (1-way and 2-way ANOVA, Bonferroni-Dunn correction, alpha=.05). RESULTS: Retentive bond strengths of FRC posts luted with MultiCore Flow in combination with the CoJet system, and of posts inserted with Rebilda DC in combination with hydrofluoric acid (HF) etching as well as with the CoJet system, were significantly higher than those of the corresponding unconditioned FRC posts (P<.001). No significant differences were noted between the bond strength values of RelyX Unicem with CoJet, MultiCore Flow with CoJet, and Rebilda DC with either CoJet or HF etching (P>.05). Retentive bond strengths were significantly lower for HF etching (Calibra, RelyX Unicem, Build-It), and for the treatment with the CoJet system in combination with Build-It compared to the corresponding control groups (P<.001). Fracture modes were primarily adhesive at the post surface or cohesive within the composite resin layer or within the FRC post. CONCLUSIONS: The retentive bond strengths differed significantly with respect to the tested combinations of conditioning method and luting composite resin.
Oper Dent. 2009 Nov-Dec;34(6):716-24.
Effect of double-application of three single-step self-etch adhesives on dentin bonding and mechanical properties of resin-dentin area.
Wei S, Shimada Y, Sadr A, Tagami J.
Tokyo Medical and Dental University, Cariology and Operative Dentistry, Department of Restorative Sciences, Tokyo, Japan. weishenghua.ope@gmail.com
PURPOSE: This study investigated whether double-application influences the bond strength of single-step self-etch adhesives and the mechanical properties of the resin-dentin area. MATERIALS AND METHODS: Three single-step self-etch adhesives (EXL-683, experimental, 3M ESPE; Clearfil Tri-S Bond, Kuraray Medical; G BOND, GC) were applied on dentin surfaces by using the single-application or double-application method. The manufacturers’ instructions stated use of the single-application method. Resin composite (Clearfil AP-X, shade A3, Kuraray Medical) was then placed and light cured for 40 seconds. The microshear bond test was carried out and the bond strength data were analyzed using one-way ANOVA with post hoc. The hardness (H) of the bonding layer, resin-dentin interface and dentin beneath the interface at depths of 10 microm and 100 microm were measured with a nanoindentation device (ENT-1100, Elionix). The H data were analyzed using two-way ANOVA, one-way ANOVA and the independent t-test at a significance level of alpha = 0.05. RESULTS: The mean bond strength with single-applications of EXL-683, Clearfil Tri-S Bond and G BOND were 39.1, 36.9 and 30.0 MPa, respectively, while with the double-application, they were 46.9, 40.2 and 32.2 MPa. Double-application for EXL-683 to dentin showed significantly higher bond strength than single-application alpha < 0.05. However, there was no significant difference between the single- and double-application methods for the other two adhesives alpha > 0.05. The H of the bonding layer was significantly influenced by both the adhesive material and application method alpha < 0.001; the H of the bonding layer with a double-application was significantly improved compared to a single-application. The H of the resin-dentin interface was significantly affected by the application method alpha < 0.001, but not by the adhesive material (alpha > 0.05). Neither the H value of dentin at 10 microm nor a depth of 100 microm was affected by the adhesive material or application method (alpha > 0.05). CONCLUSIONS: The double application of EXL-683 did improve the bond strength to dentin. The hardness of the bonding layer and resin-dentin interface was significantly affected by the double application for each material used.
Oper Dent. 2009 Nov-Dec;34(6):642-7.
Clinical evaluation of a nanofilled fissure sealant placed with different adhesive systems: 24-month results.
Yazici AR, Karaman E, Baseren M, Tuncer D, Yazici E, Unlüer S.
Hacettepe University, Faculty of Dentistry, Department of Conservative Dentistry, Ankara, Turkey. ruyay@hacettepe.edu.tr
OBJECTIVE: This clinical study compared the retention rates of a nanofilled occlusal fissure sealant placed with the use of an etch-and-rinse or a self-etch adhesive over 24 months. METHODS: Two-hundred and forty-four sealants were placed on the permanent premolars and molars of 16 subjects who had no restorations or sealants present on the fissures and no detectable caries. The sealants were placed with either SoloBond M two-step etch-and-rinse adhesive or FuturaBond NR one-step self-etch adhesive by four previously calibrated dentists, using a table of random numbers. After completion of the adhesive application, a nanofilled sealant, Grandio Seal, was applied and light-cured. Clinical evaluations were done at baseline and at 1-, 3-, 6-, 12-, 18- and 24-month recalls. Two other calibrated examiners, who were unaware of which adhesive had been used, independently evaluated the sealants. Evaluation of the sealants on every follow-up visit involved visual examination with the aid of a dental explorer and an intra-oral mirror. Each sealant was evaluated with the following criteria: 1 = completely retained; 2 = partial loss; 3 = total loss. The Pearson Chi-square test was used to evaluate differences in the retention rates among the sealants used with different adhesives for each evaluation period. RESULTS: For the 12-month recalls, complete retention rates of 89.3% for the SoloBond M group and 20.5% for the FuturaBond NR group were observed. Sixteen of the 244 restorations were unavailable after 12 months. At 24 months, a total loss of 9 sealants in the SoloBond M group and 84 in the FuturaBond NR group were observed, resulting in retention rates of 81.6% and 15.8%, respectively. There were statistically significant differences in retention rates between the SoloBond M and FuturaBond NR groups in all periods of evaluation (p < 0.05). No statistically significant difference between the retention rates for premolars and molars was found at each evaluation period (p > 0.05). There was no new caries formation throughout the 24-month recall period. CONCLUSION: Fissure sealants placed with etch-and-rinse adhesive showed better retention rates than those placed with self-etch adhesive.
Dent Mater. 2009 Nov 19. [Epub ahead of print]
Crown pull-off test (crown retention test) to evaluate the bonding effectiveness of luting agents.
R&D, Ivoclar Vivadent AG, Bendererstrasse 2, FL-9494 Schaan, Liechtenstein.
OBJECTIVE: The purpose of this review was to assess the influencing factors which affect laboratory tests that evaluate the effectiveness of luting agents on the retention of crowns in prepared dentin and – based on the results of the review – to propose a reasonable experimental setup. MATERIALS AND METHODS: The database MEDLINE was systematically searched for laboratory methods that evaluated the effectiveness of luting agents by pulling off crowns from prepared extracted teeth. RESULTS: Eighteen studies were included into the systematic review. The studies varied largely with regard to tooth type (molars, premolars), number of specimens (9-25), stump height (3-6mm), convergence angle (4.8-33 degrees ), standardization and measurement of preparation surface, seating force (25-200N), artificial ageing, crosshead speed for tensile force and statistical analysis. The coefficient of variation of the test results varied from 3% to 100%. The most important influencing factors for the crown dislodgement were stump height and convergence angle as well as the luting agent. Panavia and RelyX Unicem generally produced the highest values followed by glass ionomer and zinc phosphate cements. When pooling and normalizing the data, the mean difference between glass ionomer and resin-based materials as well as between glass ionomer and zinc phosphate cements was statistically significant (Wilcoxon, p<0.05). Seating force, roughness, type of cutting bur and use of a desensitizing agent had all a negligible effect on the test results. Artificial ageing like thermocycling had no influence with glass ionomer cements whereas for resin-based cements thermocycling and prolonged water storage generated similar a failures stress than thermocycling alone. The comparison with clinical results did not reveal conclusive evidence that the results of the laboratory methods completely reflect the results of prospective clinical trials in conjunction with single crowns and fixed dental prostheses. A reasonable experimental setup includes: at least 20 specimens per group, stump height 3mm, convergence angle 20 degrees , thermocycling of specimens (5000x), avoidance of shearing forces during dislodgement and failure probability statistics (Weibull). CONCLUSIONS: The results of pull-off tests with crowns that are cemented with luting agents varied largely and reflect only partially the results from clinical trials. The most influencing factors (standardized tooth preparation, avoidance of shearing stress during dislodgement of crown) had to be controlled to get meaningful results.
J Biomed Mater Res B Appl Biomater. 2009 Nov 19. [Epub ahead of print]
In vitro biological response to a self-adhesive resin cement under different curing strategies.
Monteiro GQ, Souza FB, Pedrosa RF, Sales GC, Castro CM, Fraga SN, Galvão BH, Braz R.
Department of Restorative Dentistry, Dental School of the University of Pernambuco-FOP/UPE, Camaragibe-PE, Brazil.
Self-adhesive resin cements represents a new approach in indirect restorative dentistry, although little is known about its biological properties. The influence of the curing strategy on the biological response of a self-adhesive resin cement (Rely-X Unicem/3M ESPE) was evaluated through methyltetrazolium (MTT) and nitric oxide (NOx) assays. Cylindrical specimens (n = 48) were prepared and cured according to the following strategies: photoactivation with halogen light-curing unit (LCU) Demetron/Kerr, LED LCU Radii/SDI, and chemical activation. A control group with culture medium and a group with lipopolysaccharide, employed for cells stimulation, were used for comparisons (n = 8). After 24 h of direct contact between specimens and rat alveolar macrophages, the biological response was evaluated. Statistical evaluation of the data was performed with Kruskal-Wallis and Dunn’s test (p = 0.05). The MTT test showed that the specimens cured by halogen light and chemical activation provided higher alterations on cell metabolism. For LED-cured specimens, cell viability was compatible to the results observed in the control group. For the NOx assay, all curing methods were cytotoxic to rat macrophages. Rely-X Unicem demonstrated different cytotoxic effects according to the curing strategy employed. (c) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Mechanical properties of new self-adhesive resin-based cement.
Nakamura T, Wakabayashi K, Kinuta S, Nishida H, Miyamae M, Yatani H.
Department of Fixed Prosthodontics, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 5650871, Japan.
PURPOSE: The aim of this study was to compare the bonding strength, flexural strength, elastic modulus, water absorption and the expansion after water storage of new self-adhesive resin cements to commercially available dental cements. METHODS: Two types (hand-mix and auto-mix) of new self-adhesive resin cements (SAC-H and SAC-A, Kuraray Medical), one conventional resin cement (Panavia F2.0), three self-adhesive resin cements (Relyx Unicem, Maxcem and G-Cem), and two resin-modified glass-ionomer cements (Fuji Luting S and Vitremer) were used. Shear bond strengths, flexural strengths and elastic moduli (ISO 4049), water absorption (ISO 4049), and the expansion rate after water storage were investigated. RESULTS: Both SAC-H and SAC-A provided adhesion to enamel and dentin, and had the same bond strength to gold alloy and zirconia as conventional resin cements. SAC-H and SAC-A had greater flexural strengths (86.4-93.5MPa) than commercial self-adhesive resin cements or glass-ionomer cements. The elastic moduli of self-adhesive and glass-ionomer cements were 5.2-7.4GPa and 2.3-3.4GPa, respectively. The water absorption of SAC-H and SAC-A (26.3-27.7mug/mm(3)) were significantly lower than commercial self-adhesive resin cements. SAC-H and SAC-A showed significantly lower expansion rates (0.17-0.26%) than commercial self-adhesive cements and glass-ionomer cements after 4 weeks water storage. CONCLUSIONS: It is suggested that the new self-adhesive resin cements exhibited a favorable bonding capability and mechanical properties.
Quintessence Int. 2009 Oct;40(9):763-72.
Effect of adhesive agent and fissure morphology on the in vitro microleakage and penetrability of pit and fissure sealants.
Marks D, Owens BM, Johnson WW.
Objective: To evaluate the effect of adhesive agents and fissure morphology on the microleakage and penetrability of pit and fissure sealants. Method and Materials: Sealants used in this study included Aegis (Bosworth), conseal f (Southern Dental Industries), and Admira Seal (Voco). Adhesive agents included Optibond Solo Plus (sds/Kerr) and Clearfil S3Bond (Kuraray). Ninety extracted permanent molars were randomly assigned to 9 groups combining sealant and adhesive agent materials. A sealant and control group (phosphoric acid etch only) was also included. Dye penetration (microleakage), penetrability, and fissure morphology assessment was performed for the treatment groups through microscopic evaluation. Results: Significant (P = .003) differences in microleakage were exhibited, with the Aegis + control and Aegis + Optibond Solo Plus groups displaying less leakage, while significant (P = .03) differences were also noted between groups regarding penetrability. Fissure morphology was not a significant (P = .82) factor affecting microleakage; however, fissure type did significantly (P < .001) impact penetrability. No correlation was found between the extent of microleakage and penetrability. Conclusion: Application of sealants using phosphoric acid as a conditioning agent revealed superior results, while the use of adhesives was found to be unnecessary. (Quintessence Int 2009;40:763-772).
Eur J Dent. 2009 Oct;3(4):290-6.
Bond Strength of One-Step Adhesives under Different Substrate Moisture Conditions.
Faria-E-Silva AL, Fabião MM, Sfalcin RA, de Souza Meneses M, Santos-Filho PC, Soares PV, Martins LR.
Professor of Dentistry Department, State University of Montes Claros, Brazil.
OBJECTIVES: The aim of this study was to evaluate the bond strength of one-step adhesive systems to dry or moist dental substrate. METHODS: Thirty human third molars were sectioned into two halves, in the mesio-distal direction, parallel to the long axis of the tooth. Each half was embedded in a polystyrene resin cylinder so that the buccal/lingual surface remained exposed. This exposed surface was abraded to obtain both flat exposed enamel and dentin. The samples were randomly allocated according to the adhesive system (Xeno III, Adper Prompt and iBond) and moisture condition (dry and moist). The substrates were air-dried for 30 s for dry condition, while the moist substrates were re-wet with 2.5 mul of distilled water after drying. After the adhesive procedures, two resin composite cylinders were build-up on dentin and enamel substrates, totaling four per sample. A shear load was applied to the samples at a crosshead speed of 0.5 mm/min until failure. Data were statistically analyzed by three-way ANOVA and the Tukey test (alpha=0.05). RESULTS: The evaluated one-step adhesives showed higher bond strength to dentin than enamel. The iBond presented better bond performance to moist substrate and Xeno III to dry substrate. The moisture condition did not interfere in the performance of Adper Prompt. The Xeno III and iBond presented higher bond strength than the other adhesives to both dry and moist substrates. CONCLUSIONS: The moisture condition of substrate interfered in the performance of one-step self-etching adhesives and the best moisture condition was material dependent.
Dent Mater J. 2009 Sep;28(5):578-86.
Effects of coating root dentin surfaces with adhesive materials.
Tajima K, Nikaido T, Inoue G, Ikeda M, Tagami J.
Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University.
The aim of this study was to evaluate the effects of coating root dentin surfaces with adhesives vis-à-vis the prevention of root dentin demineralization. Root dentin surface was ground with #600 SiC, and then either a single coat of Clearfil SE Bond (SE), Clearfil Tri-S Bond (TS), G-Bond (GB), Hybrid Bond (HB-1), or two coats of HB (HB-2) were applied. Specimens were immersed in an artificial demineralizing solution, then sectioned through the center of the root and polished. Thickness of the coating layer and depth of the demineralized dentin layer were observed under a confocal laser scanning microscope (CLSM). Nanohardness values of the coating layer and underlying dentin were measured using a nanoindentation tester. All obtained data were statistically analyzed. Dentin demineralization was not observed in the surface coating groups with the exception of HB-1, and nanohardness of the underlying dentin was comparable to that of normal dentin. Based on the results obtained, it seemed that coating root dentin surfaces with an adhesive material is a promising good practice to prevent demineralization.
Dent Mater J. 2009 Sep;28(5):565-70.
Effect of fiber-premixed indirect resin composite substructure on fracture resistance of MOD composite inlays adhered with two different adhesive resin cements.
Minami H, Suzuki S, Murahara S, Saimi Y, Minesaki Y, Tanaka T.
Fixed Prosthetic Clinic, Kagoshima University Medical and Dental Hospital.
This study evaluated the effect of a fiber-premixed indirect resin composite (FMC) substructure on the fracture resistance of mesialocclusal-distal (MOD) indirect composite restorations adhered to extracted human upper premolars. The teeth received a standardized MOD cavity preparation, and indirect composite inlays were fabricated with or without using the FMC. Inlays were cemented into the cavity preparations using either Super-Bond C&B or Panavia F2.0. A total of 28 specimens, namely seven specimens for four groups, were thus fabricated. Failure load and failure energy were determined after thermocycling (4-60 degrees C for 5,000 cycles). In terms of failure load, no significant differences were found among the four groups. In terms of failure energy, FMC substructure exerted a significantly favorable effect on Super-Bond C&B-bonded group but a negative one on Panavia F2.0-bonded group. In conclusion, the failure energy of the group using FMC substructure and which was adhered using Super-Bond C&B was significantly higher than the other groups.
Braz Dent J. 2009;20(3):195-200.
In vitro potential cytotoxicity of an adhesive system to alveolar macrophages.
Porto IC, Andrade AK, Guênes GM, Ribeiro AI, Braz R, Castro CM.
Department of Restorative Dentistry, University of Pernambuco, Camaragibe, PE, Brazil. isabelcmporto@gmail.com
The purpose of this study was to evaluate the potential cytotoxicity of Adper Single Bond 2 (SB) simplified etch-and-rinse adhesive system in alveolar macrophage cultures, as a function of the post-polymerization time and duration of immersion in the culture medium for preparation of extracts, by observing the levels of nitric oxide (NO) release and cell survival rate (MTT assay). Wistar rat alveolar macrophages were exposed to 200 microL of extracts obtained from 24- or 72-h immersion of adhesive samples in culture medium (RPMI), immediately or 24 h after polymerization. Fresh RPMI and E. coli lipopolysaccharides were used as negative and positive controls, respectively. The cells were placed in a humidified incubator for 24 h. The results were analyzed by the Student’s-t test (alpha=5%). The amount of NO produced and viable cells were significantly different (p<0.05) between the experimental and the control groups, showing that, irrespective of the post-polymerization time and duration of immersion in the culture medium, the adhesive system caused intense cytotoxicity to the macrophages. The cytotoxic effects were not statistically different (p<0.05) among the experimental groups. In conclusion, chemical components released from SB in aqueous environment were highly toxic to cell culture and thus an inflammatory pulpal response should be considered during the clinical application of dental adhesives.
J Prosthet Dent. 2009 Oct;102(4):242-52.
Evaluation of shear and tensile bond strength between dentin and ceramics using dual-polymerizing resin cements.
Department of Dentistry, Dumlupinar University, Kutahya, Turkey. gurelp@gmail.com
STATEMENT OF PROBLEM: The applications of dual-polymerizing resin cements for all-ceramic restorations have considerably increased. For a successful clinical outcome, the luting agent should have high bond strength, not only to the ceramic surface, but also to the tooth surface. PURPOSE: The purpose of this study was to examine shear (S) and tensile (T) bond strengths between 2 all-ceramic systems and human dentin using 3 dual-polymerizing resin cements. MATERIAL AND METHODS: The buccal surfaces of 120 freshly extracted human third molars were ground flat, parallel to the long axis. Sixty specimens were prepared from each of 2 all-ceramic systems (IPS Empress 2 (E) and Cergo Pressable Ceramic (C)). Twenty specimens were luted with each of the following resin cements: Nexus 2 (N) with Self-Etch Primer, Duo-Link (D), and Variolink II (V), with their respective bonding systems. All specimens were immersed in water at 37 degrees C for 1 week, before being thermal cycled for 500 cycles in 5 degrees C and 55 degrees C water. Shear (S) and tensile (T) bond strength tests were applied to 10 specimens from each group. Fractured surfaces were inspected by scanning electron microscopy (SEM). Statistical analyses were performed using nonparametric 1-way ANOVA (Kruskal-Wallis) followed by Duncan’s multiple range tests for post hoc comparison and Mann-Whitney U test for 2 ceramic systems (alpha=.05). RESULTS: Significant differences were observed in shear and tensile bond strength values of the adhesive systems used (P<.05). Duo-Link showed the highest mean bond strength values, whereas Nexus 2 revealed lower shear and tensile bond strength values. Fracture modes were hybrid at the dentin interface and/or cohesive in dentin. CONCLUSIONS: Cementing agents/adhesive systems may influence the bond to dental hard tissues. Dual-polymerizing activators may have a negative effect on polymerization of the bonding agent.
J Dent. 2009 Sep 22. [Epub ahead of print]
In Vitro Evaluation of Bonding Effectiveness to Dentin of All-in-One Adhesives.
Margvelashvili M, Goracci C, Beloica M, Papacchini F, Ferrari M.
Department of Dental Materials and Fixed Prosthodontcis, University of Siena, Policlinico ‘Le Scotte’, Viale Bracci, 53100 Siena, Italy.
OBJECTIVES: The study was aimed at assessing the bonding potential of all-in-one adhesives to dentin. METHODS: The microtensile bond strength of the all-in-one adhesives Bond Force (Tokuyama), AdheSE One (Ivoclar Vivadent), and Xeno V (Dentsply) was measured in comparison with the etch-and-rinse system XP Bond (Dentsply). The ultrastructural characteristics of dentin-adhesive interface were observed under scanning electron microscope (SEM). Twenty human extracted third molars had their mid-coronal dentin exposed and ground with wet 600-grit SiC paper in order to create a standardized smear layer. Bonding procedures were performed according to the manufacturers’ instructions and microtensile beams were obtained with the “non-trimming” technique. The bond strengths in MPa were statistically analyzed including pre-test failures as “zero” values (Kolmogorov-Smirnov test, Levene’s test, One-Way ANOVA, Tukey test p<0.05). RESULTS: The following bond strengths were recorded in MPa (mean+/-standard deviation): AdheSE One 31.7+/-21.3; Xeno V 42.8+/-26.4; Bond Force 43.3+/-22.1; XP Bond 51.9+/-18.6. The statistical analysis demonstrated that the bond strengths achieved by Bond Force and Xeno V were similar to that of the etch-and-rinse adhesive, whereas the bond strength of AdheSE One was significantly lower. A distinct hybrid layer with resin tags was seen only in XP Bond specimens. All-in-one adhesives demonstrated a rather superficial interaction with the dentin substrate. CONCLUSIONS: although the strongest bond to dentin was established by the etch-and-rinse system, however the all-in-one adhesives containing organic solvents reached bond strength levels that were comparable from a statistical point of view.
J Dent. 2009 Sep 22. [Epub ahead of print]
Resin-dentine interfacial morphology following CPP-ACP treatment.
Adebayo OA, Burrow MF, Tyas MJ.
Melbourne Dental School, University of Melbourne, 720 Swanston Street, Victoria 3010, Australia.
OBJECTIVES: To evaluate the quality of bonded resin-dentine interfaces produced by two self-etching primer adhesives after casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) treatment, in comparison to untreated dentine. METHODS: Thirty-four adult molar teeth were sectioned to obtain dentine with tubule orientations parallel/oblique or perpendicular to the surface. The specimens were divided into ’smear layer’ (1A, 1B) and ‘no smear layer’ groups, after treatment with 15% EDTA (2A, 2B). The specimens were then left either untreated (1A, 2A) or treated (1B, 2B) with CPP-ACP paste (Tooth Mousse, GC Corp.) for 60min x 7 days. Each treatment group was divided into three subgroups and specimens etched/conditioned (No conditioning; 30 – 40% phosphoric acid (H(3)PO(4)); 20% polyacrylic acid) and bonded with either a 2-step self-etching primer adhesive (Clearfil SE Bond, Kuraray Medical) or an ‘all-in-one’ adhesive (G-Bond, GC Corp.) and a hybrid resin composite. After 24-h water storage, the bonded specimens were sectioned, polished up to 4,000-grit abrasive silicon carbide paper and 0.25-mum diamond paste, prepared for FE-SEM using the acid-base technique, critical point dried, gold-coated and examined. Bonded and fractured dentine interfaces were also prepared and examined. RESULTS: The 2-step adhesive produced a similar appearance of bonded resin-dentine interface irrespective of smear layer group, treatment or etching/conditioning. After polyacrylic acid conditioning, the ‘all-in-one’ adhesive exhibited more areas with bond failures. The bond failures were within the hybrid layer and more pronounced following CPP-ACP treatment. CONCLUSION: The quality of the bonded resin-dentine interface produced after CPP-ACP treatment may depend on the adhesive system used.
Comment in:
J Esthet Restor Dent. 2009;21(2):132.
Temperature changes in silorane-, ormocer-, and dimethacrylate-based composites and pulp chamber roof during light-curing.
Miletic V, Ivanovic V, Dzeletovic B, Lezaja M.
Edinburgh Postgraduate Dental Institute, The University of Edinburgh, Lauriston Place, Edinburgh, UK. vesna.miletic@gmail.com
STATEMENT OF THE PROBLEM: Light-curing of resin-based composites (RBCs) is associated with temperature increase in the pulp chamber, which may have a detrimental effect on the vital pulp. PURPOSE: The purpose of the study was to evaluate temperature changes of silorane-, ormocer-, and dimethacrylate-based RBCs at the bottom surface of the RBC and in the pulp chamber roof dentin (PCRD) during curing. MATERIALS AND METHODS: In part A, temperatures were measured for Filtek LS (3M ESPE, St. Paul, MN, USA), Admira (Voco GmbH, Cuxhaven, Germany), and Herculite XRV (Kerr Corp., Orange, CA, USA) with a high-power light-emitting diode (LED) unit by placing thermocouples in contact with the bottom surface of the material in standardized acrylic molds. In part B, temperature changes in PCRD were measured in extracted molars during light-curing of adhesives and RBCs in 2-mm-deep cavities with a remaining dentin thickness (RDT) of 1 mm. RESULTS: Filtek LS showed a different temperature curve compared with Admira and Herculite XRV. Significantly higher temperatures were recorded for Filtek LS (p < 0.001) than for Admira and Herculite XRV in acrylic molds. Temperature rises recorded in PCRD for adhesives and RBCs were between 4.1 and 6.4 degrees C. No significant differences in PCRD temperatures were found between the three groups during adhesive curing and RBC curing (p > 0.05). CONCLUSIONS: Filtek LS showed a different heat-generation pattern from and significantly higher temperatures than Admira and Herculite XRV when the materials were tested in acrylic molds. Similar temperatures were recorded in the PCRD during curing of adhesives and RBCs. CLINICAL SIGNIFICANCE: Although a substantial temperature rise in the bulk material occurred during light-curing of the three resin-based composites, a remaining dentin thickness of 1 mm caused a significant reduction in pulp chamber roof dentin temperatures. Temperatures measured in the pulp chamber roof dentin corresponding to the zone occupied by the postmitotic odontoblast layer were not statistically different for the three types of resin-based composites.
Aust Orthod J. 2009 May;25(1):19-23.
Effect of adhesive types on enamel discolouration around orthodontic brackets.
Jahanbin A, Ameri H, Khaleghimoghaddam R.
Department of Orthodontics, Mashhad Dental School Research Center, Mashhad University of Medical Sciences, Iran. Jahanabina@mums.ac.ir
BACKGROUND: Unsightly colour changes may occur in the enamel around bonded orthodontic brackets. AIM: To determine the enamel colour changes around orthodontic brackets bonded with different adhesives. METHODS: One hundred extracted upper first premolars were divided into five equal groups. Fiducial holes were drilled in the buccal and palatal surfaces of the teeth and metal orthodontic brackets were bonded to the buccal surfaces with different combinations of adhesives and primers. The teeth were immersed in a tea-coffee solution for one week. The brackets were then debonded and the teeth polished. The colour of the enamel surface was measured around each fiducial hole before bonding (baseline), after debonding and after polishing. The colour differences (deltaE) were compared using one-way ANOVA and the paired t-test. RESULTS: There were no significant differences between the five adhesive groups in baseline-debonding deltaE and baseline-polishing deltaE, but statistically significant differences were found between the baseline-debonding deltaE on the buccal and palatal surfaces and the baseline-debonding deltaE versus baseline-polishing deltaE on the buccal surfaces. Although statistically significant, the colour changes would not be visible to many observers. Approximately 75 per cent of the staining was attributed to the enamel components. CONCLUSIONS: The type of adhesive and the methods of application had no effect on enamel colour change. Most of the colour change was attributed to uptake of stain by the components of the enamel, not the resin tags.
Eur J Oral Sci. 2009 Aug;117(4):463-9.
Degree of conversion and interfacial nanoleakage expression of three one-step self-etch adhesives.
Navarra CO, Cadenaro M, Codan B, Mazzoni A, Sergo V, De Stefano Dorigo E, Breschi L.
Division of Dental Sciences and Biomaterials, Department of Biomedicine, University of Trieste, Trieste, Italy.
Suboptimally polymerized monomers may be responsible for the reduced material properties of simplified adhesives and their inherent bonded interface instability. This study was performed to determine the degree of cure within the hybrid layers produced by three one-step self-etch adhesives in situ using Raman microspectroscopy and to investigate nanoleakage expression. Dentin disks were bonded with AdheSE One, Adper Prompt L-Pop, or iBond. Composite layers of 2-mm thickness were built up in bulk on the polymerized adhesive surfaces and then the adhesive-dentin interfaces were exposed to a micro-Raman beam. Adhesive penetration was calculated using the relative intensities of bands associated with mineral and adhesive, and the degree of conversion (DC) was evaluated. Interfacial nanoleakage expression was evaluated on the same specimens. The DC values for the tested adhesives were found to increase in the following order: AdheSE One (48 +/- 16%) < Adper Prompt L-Pop (83 +/- 2%) = iBond (90 +/- 6%; P < 0.05). AdheSE One showed greater nanoleakage expression than iBond or Adper Prompt L-Pop. Increased nanoleakage expression was associated with AdheSE One that showed the lowest DC. This suggests that a low DC may affect the quality and the long-term stability of the adhesive interface owing to the elution of unreacted monomers forming a porous and highly permeable hybrid layer.
Dent Mater. 2009 Jul 24. [Epub ahead of print]
Influence of the hydrostatic pulpal pressure on droplets formation in current etch-and-rinse and self-etch adhesives: A video rate/TSM microscopy and fluid filtration study.
Sauro S, Mannocci F, Toledano M, Osorio R, Thompson I, Watson TF.
Biomaterials, Biomimetics & Biophotonics, King’s College London Dental Institute at Guy’s, King’s College and St. Thomas’ Hospitals, Floor 17 Guy’s Hospital, London, UK.
OBJECTIVES: The aim of this study was to investigate the droplet formation using a real-time/confocal microscopy technique, when different self-etching and etch-and-rinse adhesives were applied in the presence or absence of pulpal pressure. Resin-dentin permeability (%P) was also evaluated. METHODS: Optibond FL, Silorane adhesive, Scotchbond 1XT, G-Bond and DC-Bond were bonded in the presence or in absence of simulated pulpal pressure. A fluid-transport model was used to measure the water permeability through resin-bonded dentin. Half of the specimens bonded in the presence of the hydrostatic pulpal pressure (20cm H(2)O) were light cured, whereas the remnant half received no light curing. The same was done with the half of the specimens bonded under no pulpal pressure. The specimens were investigated under a confocal TSM. RESULTS: Optibond FL and G-Bond had the lowest dentin permeability. Optibond FL adhesive showed few water droplets on the polymerized external surface and within the resin-dentin interface. G-Bond showed static interfacial globular-like droplet formation. DC-Bond and Scotchbond 1XT were the most water permeable adhesives both in the presence and in absence of pulpal pressure. A dynamic interfacial non-globular-like droplet formation was observed. Severe droplet formation was observed on the polymerized external surface. SIGNIFICANCE: The presence of the pulpal pressure may cause increasing in fluid filtration and droplet formation in simplified adhesives containing HEMA. The adhesives containing 4-META (G-Bond) may be affected by static phase separation but by very low osmotic droplets formation and water permeability. The three-step adhesives are less affected by these problems.
J Biomater Sci Polym Ed. 2009;20(11):1597-610.
The Effects of One-Step Self-Etch Adhesives on the Induction of Oxidative Stress and Production of TGF-beta1 and BMP-2 by Human Gingival Fibroblasts.
Guven G, Cehreli SB, Altun C, Cehreli ZC, Serdar MA, Ural AU.
Department of Pediatric Dentistry, Center of Dental Sciences, Gulhane Medical Academy, Etlik 06018, Ankara, Turkey.
The aim of this study was to evaluate and compare the effects of two self-etch adhesive materials on the induction of oxidative stress and production of transforming growth factor-beta1 (TGF-beta1) and bone morphogenetic protein-2 (BMP-2) by cultured human gingival fibroblasts (HGF). Inflammation-free attached gingiva was obtained from healthy donors under informed consent. Following 24- and 72-h exposure of HGF to two different elutes of the test materials, cell viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Lipid peroxidation, a major indicator of oxidative stress, was measured by the thiobarbituric acid reactive substance (TBARS) assay. TGF-beta1 and BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay (ELISA). Cell viability of the test groups was significantly lower than those of control at 24 and 72 h (P < 0.001), but showed an increase at 72 h (P < 0.001). The TBARS levels of both test groups were significantly greater than that of control (P < 0.05), and displayed similar values at 72 h (P > 0.05). For both materials, the levels of TGF-beta1 and BMP-2 were significantly greater than that of control (P < 0.05). Both test groups showed increased TGF-beta1 levels. These results indicate that the tested self-etch adhesives might be capable of inducing production of TGF-beta1 and BMP-2 in cultured HGF, despite their cytotoxic and oxidative stress-producing potential.
Acta Odontol Latinoam. 2009;22(1):47-56.
Comparative study of the microtensile bond strength of three different total etch adhesives with different solvents to wet and dry dentin (in vitro test).
Orellana N, Ramírez R, Roig M, Giner L, Mercade M, Durán F, Herrera G.
Dental School, Los Andes University, Mérida, Venezuela. noeorellana@yahoo.com
The aim of this study was to compare the microtensile bond strength of three different total etch adhesives: XP Bond (Caulk-Dentsply) versus Excite (Ivoclar/Vivadent) and Prime & Bond NT (Caulk-Dentsply). Forty two (42) third human molars were cut to expose the dentinal surface. They were divided into three groups of 14 teeth (GI: XP Bond, G2: Excite, G3: Prime & Bond NT) and two groups of seven teeth for each moisture condition: moist dentin (GM) and dry dentin, (GD). The total-etch technique was used with each moisture variation. The adhesives and composites A3 (Ceram Duo GI, G3 and Tetric Ceram G2) were applied according to manufacturer’s instructions. Teeth were cut with an ISOMET 1000 (Buehler Ltd.) to obtain 1 mm2 x 10 mm bars, which were subject to a traction test at 5 mm/min in a universal testing machine (Adamel Lhomargy DY 36). The collected data were recorded and analyzed using an experimental design for studying two factors offixed effrcts with software Statgraphics version 5.1. For the variable type of adhesive, we found p = 0.000, for the variable substrate condition, p = 0.0012, and for interaction between both factors, p = 0.0457, which indicates significant statistical differences. The values for microtensile bond strength were G1M = 55.0642 MPa Standard deviation (SD) 3.09768; G1D 39.115 MPa SD 2.86789; G2M 34.1607 MPa SD 2.86789; G2D = 32.7373 MPa SD 2.77065; G3M 3 7.3407 MPa SD 2.86789 and G3D = 31.0593 MPa SD 2.77065. XP Bond showed the greatest values of micmtensile bond strength under both conditions. Moist substrate increases the values of micmtensile bond stren gth]br the adhesives tested; howeve, Excite shows lower susceptibility to variation of dentinal moisture.
J Dent. 2009 Jun 16. [Epub ahead of print]
Improving the effect of NaOCl pretreatment on bonding to caries-affected dentin using self-etch adhesives.
Taniguchi G, Nakajima M, Hosaka K, Iwamoto N, Ikeda M, Foxton RM, Tagami J.
Cariology and Operative Dentistry, Department of Restorative Science, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan.
OBJECTIVE: To evaluate the effect of sodium hypochlorite pretreatment on adhesion to normal and caries-affected dentin using self-etch adhesives. METHODS: Forty extracted human molars with coronal carious lesions were used in this experiment. The occlusal dentin surfaces including the caries-affected dentin in each group were treated as follows: group 1, rinsed with water; group 2, treated with 6% NaOCl for 15s; group 3, treated with 6% NaOCl for 30s; group 4, application with Accel for 30s after NaOCl-30s pretreatment. After rinsing with water and air-drying, the treated dentin surfaces were applied with self-etch systems (Bond Force and Clearfil Protect Bond) according to the manufacturers’ instructions, and built-up with resin composite. After 37 degrees C water storage for 24h, the bonded normal or caries-affected dentin areas were isolated to create an hourglass configuration with a cross-sectional area of approximately 1mm(2). The specimens were subjected to tensile stress at a cross-head speed of 1.0mm/min. RESULTS: NaOCl-15s pretreatment significantly improved the muTBS of both self-etch adhesives to caries-affected dentin, while the 30s pretreatment did not affect them. For normal dentin, NaOCl-30s pretreatment significantly reduced the muTBS of both self-etch adhesives although the 15s pretreatment did not alter them. Furthermore, the application of Accel with a reducing effect increased the muTBS to normal and caries-affected dentin treated with NaOCl for 30s. CONCLUSIONS: The effects of NaOCl pretreatment on bonding of both self-etch adhesives were dependent upon type of dentin (normal and caries-affected dentin) and the treatment time.
Oper Dent. 2009 May-Jun;34(3):328-36.
The influence of luting systems on the microtensile bond strength of dentin to indirect resin-based composite and ceramic restorations.
D’Arcangelo C, De Angelis F, D’Amario M, Zazzeroni S, Ciampoli C, Caputi S.
Department of Operative Dentistry, Dental School, University of Chieti, Chieti, Italy. cdarcang@unich.it
Microtensile bond strength (microTBS) evaluation and fractographic analysis were used to compare four luting systems in the cementation of resin-based composite (RBC) and ceramic disks to dentin. Forty freshly-extracted molars were transversally sectioned to expose flat, deep dentin surfaces. Forty cylindrical specimens (5-mm diameter and 10-mm height), consisting of 20 RBC disks and 20 leucite-based glass ceramic disks, were produced. The RBC disks were sandblasted with 50-microm Al2O3. The ceramic disks were conditioned with 9.5% hydrofluoric acid gel and silane application. All the disks were then bonded to dentin surfaces according to the luting cements to be used: two etch-and-rinse luting agents (XP bond/CoreXFlow; Dentsply [XP]) (Enabond/EnaCem HF; Micerium [ENA]), a self-etch luting system (ED Primer II A+B/Panavia F2.0; Kuraray-Dental [PAN]) and a self-adhesive luting agent (RelyX Unicem; 3M ESPE [UNI]). The adhesive/luting cement systems were applied according to the manufacturers’ instructions. The specimens were sectioned perpendicular to the adhesive interface to produce multiple beams, approximately 1 mm2 in area. All the specimen preparations were performed by the same operator. The beams were tested under tension at a crosshead speed of 0.5 mm/minute until failure. The microTBS data were analyzed by two different one-way-ANOVA and multiple comparison Tukey tests (alpha = 0.05). All the fractured beams were observed using a Scanning Electron Microscope (SEM) at 200x magnification for fracture mode determination. The mean bond strength in MPa (SD) for the RBC (Co) and ceramic (Ce) groups were: XP-Co = 31.39 (13.51), ENA-Co = 30.93 (10.17), PAN-Co = 18.29 (10.02), UNI-Co = 19.33 (7.91); XP-Ce = 4.83 (1.86), ENA-Ce = 5.15 (1.66), PAN-Ce = 4.36 (1.80), UNI-Ce = 7.16 (2.52). Statistical analysis showed that the bond strengths were significantly affected by the luting agent employed for both the RBC and ceramic groups (p<0.001). In particular, the XP-Co group and the ENA-Co group did not differ from each other (p > 0.05) and showed significantly higher bond strengths than the PAN-Co and UNI-Co groups (p < 0.05). On the contrary, the UNI-Ce group showed the highest bond strengths compared to the other ceramic experimental groups (p < 0.05). Regarding failure mode, differences were found between the RBC groups: for the etch-and-rinse luting systems (XP-Co and ENA-Co groups), most failures occurred cohesively in the luting agent, while the self-etch luting system (PAN-Co group) and self-adhesive luting system (UNI-Co group) failed predominantly adhesively at the luting agent-dentin interface. Little differences were found between the ceramic groups, where failure type was primarily adhesive between cement and ceramic.
Oper Dent. 2009 May-Jun;34(3):280-7.
Bond strength of resin cements to a zirconia ceramic with different surface treatments.
Cavalcanti AN, Foxton RM, Watson TF, Oliveira MT, Giannini M, Marchi GM.
Department of Restorative Dentistry, Piracicaba Dental School, UNICAMP, Piracicaba, Brazil. dea.cavalcanti@uol.com.br
This study evaluated the influence of surface treatments and metal primers on the bond strength of resin cements to a yttrium-stabilized tetragonal zirconia (Y-TZP) ceramic. Two-hundred and forty plates of Y-TZP ceramic were randomly assigned to 24 groups (n = 10) according to the combination of surface treatment (none, air abrasion with Al2O3 particles, Er:YAG laser irradiation), metal primer (none, Alloy Primer, Metal Primer II or Metaltite) and resin cement (Calibra [Bis-GMA-based] or Panavia F2.0 [MDP-based]). Fragments of dentin with a cylindrical edge (0.8 mm in diameter) were fixed to ceramic surfaces with the resin cements. The micro-shear bond test was carried out at a 1 mm/minute speed until failure, and the ceramic surfaces were examined after debonding. Bond strengths were analyzed through three-way ANOVA/Tukey test with a 5% significance level. Changes in topography after surface treatments were evaluated with scanning electron microscopy. Surface treatments significantly modified the topography of the Y-TZP ceramic. Air abrasion resulted in increased bond strength for both resin cements. However, air abraded and laser irradiated specimens presented higher bond strength with the Bis-GMA-based resin cement than with the MDP-based cement. Both cements presented similar behavior on untreated surfaces. The three metal primers yielded a significant increase in bond strength, regardless of the surface treatment and resin cement. Adhesive failures were the most prevalent. Air abrasion with Al2O3 particles and the application of metal primers increased bond strength to Y-TZP surfaces for both resin cements.
J Dent Res. 2009 May;88(5):443-8.
Degradation-stage effect of self-etching primer on dentin bond durability.
Aida M, Odaki M, Fujita K, Kitagawa T, Teshima I, Suzuki K, Nishiyama N.
Department of Crown Bridge Prosthodontics, Nihon University School of Dentistry at Matsudo, 870-1 Sakaecho, Nishi 2, Matsudo, Chiba 271-8587, Japan. aida.masahiro@nihon-u.ac.jp
It is well-known that self-etching primers can be altered. However, the effects from altered primers on the dentin bond durability have yet to be thoroughly identified. In this study, we examined the effects from 5 altered Liquid A primers in different stages of degradation-where 2-hydroxyethylmethacrylate (HEMA) and 10-methacryloyloxydecyl dihydrogen phosphate (MDP), used in Liquid A primers, were altered by the hydrolysis of the methacryloxy ester portion in the HEMA and MDP-on the hybrid layer’s quality and dentin bond durability. The hypothesis was that degradation stages of altered Liquid A primers have no effect on the hybrid layer’s quality and on dentin bond durability. Bond strengths, obtained after thermo-cycling, were strongly dependent on the degradation stage of the altered Liquid A primer. Alterations of self-etching primers reduced dentin bond durability and decreased the created hybrid layer’s quality.
J Adhes Dent. 2009 Apr;11(2):109-15.
The influence of adhesive thickness on the microtensile bond strength of three adhesive systems.
D’Arcangelo C, Vanini L, Prosperi GD, Di Bussolo G, De Angelis F, D’Amario M, Caputi S.
Department of Operative Dentistry, Dental School, University of Chieti, Italy. cdarcang@unich.it
PURPOSE: To evaluate the effects of multiple adhesive layers of three etch-and-rinse adhesives on both adhesive thickness and microtensile bond strength (microTBS). MATERIALS AND METHODS: Midcoronal occlusal dentin of 36 extracted human molars was used. Teeth were randomly assigned to 3 groups (EB, XP, PQ) according to the adhesive system to be used: PQ1 (Ultradent) (PQ), EnaBond (Micerium) (EB), or XP Bond (Dentsply/DeTrey) (XP). Specimens from each group were further divided into three subgroups according to the number of adhesive coatings (1, 2, or 3). In all subgroups, each adhesive layer was light cured before application of each additional layer. After bonding procedures, composite crowns were incrementally built up. Specimens were sectioned perpendicular to the adhesive interface to produce multiple beams, approximately 1 mm2 in area. Beams were tested under tension at a crosshead speed of 0.5 mm/min until failure. Adhesive thicknesses and failure modes were evaluated with SEM. The microTBS data and mean adhesive thickness were analyzed by two-way ANOVA and multiple-comparison Tukey’s test (alpha = 0.05). RESULTS: The mean bond strength (in MPa (SD)) of group EB gradually increased from 1 to 3 consecutive coatings (27.02 (9.38) to 44.32 (4.93), respectively) (p < 0.05). The highest mean bond strengths for the PQ (46.66 (12.95)) and XP groups (40.55 (5.69)) were obtained applying two adhesive coatings. The mean thickness of the adhesive layer (in microm (SD)) significantly increased with the number of coatings (p < 0.05), ranging from 29.45 (1.42) to 77.64 (1.10) for PQ, from 5.12 (0.68) to 37.75 (0.92) for EB, and from 12.64 (0.68) to 37.92 (0.71) for the XP group. Failure modes for EB specimens were mainly classified as adhesive failure between adhesive and dentin. The XP3 and PQ3 subgroups showed a greater number of total cohesive failure in adhesive. CONCLUSION: Multiple adhesive coats significantly affected bond strength to dentin. An excess of adhesive layer thickness can negatively influence the strength and the quality of adhesion.
J Clin Pediatr Dent. 2009 Spring;33(3):223-30.
Ultramorphological characterization of the resin dentin interface–an in vitro analysis of nanoleakage patterns of dentin adhesives.
Neelakantan P, Sanjeev K, Rao CV.
Department of Conservative Dentistry and Endodontics, College of Dental Surgery, Saveetha University, Chennai, Tamil Nadu, India. prasu_endo@yahoo.com
AIM AND DESIGN: The requirements of an effective dentin adhesive system include the ability to thoroughly infiltrate the collagen network and partially demineralized zone, to encapsulate the collagen and hydroxyapatite crystallites, to produce a well polymerized durable hybrid layer with high bond strengths. Microleak-age and marginal percolation are the most detrimental factors thwarting the success of any restoration. However the presence of leakage pathways, called nanoleakage have been observed in the hybrid layer, even in the absence of microleakage. The nanoleakage patterns of four dentin adhesives (Prime & Bond NT, AdheSE, Clearfil S3 bond and Fuji Bond LC) was compared using Scanning electron microscopy and Energy Dispersive Spectroscopy, by the silver nitrate penetration method. RESULTS AND CONCLUSION: The results indicated that etch and rinse adhesives showed the maximum nanoleakage followed by the self etch systems. The glass ionomer based bonding agents showed the least nanoleakage. It is extremely important to take nanoleakage as a consideration while choosing dentin adhesives, to ensure success of the restoration.
J Prosthodont. 2009 May 8. [Epub ahead of print]
Effect of Two Self-Adhesive Cements on Marginal Adaptation and Strength of Esthetic Ceramic CAD/CAM Molar Crowns.
Mörmann W, Wolf D, Ender A, Bindl A, Göhring T, Attin T.
Professor and Director, Division of Computer Restorations, Department of Preventive Dentistry, Periodontology and Cariology, Center for Dental and Oral Medicine, University of Zurich, Switzerland.
Abstract Purpose: This study evaluated the effects of adhesive cements on marginal adaptation and fracture resistance of ceramic molar crowns. Materials and Methods: Seventy-five extracted maxillary molars were selected. The occlusal morphology of 15 molars (control) was scanned and transferred to the crowns in the test groups by CAD/CAM. Sixty molars received full-coverage crown preparations with 6-degree axial taper, 1.0-mm shoulder, and 2.0-mm occlusal reduction. They were assigned to four groups, and pulpal pressure was simulated. The 15 crowns in each test group were seated with resin-based self-adhesive cements, Rely-X (RX) and Multilink (MS), one multistep bonded adhesive luting composite resin, Variolink (VL), and glass-ionomer cement, Ketac Cem (KC). Test and control molars were subjected to thermal and mechanical fatigue stress (TMS: 12,000 x 5 degrees C to 50 degrees C; 2.4 million x 49 N) for 18 days in a masticator. Marginal adaptation ["continuous margin%" (CM%)] of the crowns was determined by scanning electron microscopy (200x). Finally, molars were occlusally loaded until fracture in a testing machine, and fracture load (N) was recorded. Marginal adaptation and strength data were statistically analyzed. Results: TMS significantly (p < 0.001) reduced CM% in all groups. After TMS, CM% at the cement-dentin interface was significantly (p < 0.001) higher for RX than for all other cements. At the crown-cement interface both self-adhesive cements MS and RX had significantly better CM% than VL (p < 0.05) and KC (p < 0.001). Fracture resistance of natural untreated molars was significantly (p < 0.001) higher than that of experimental crowns. Fracture resistance of RX cemented crowns was significantly (p < 0.05) higher than that of other crowns. Occlusal morphology significantly influenced fracture resistance (p < 0.05). Conclusions: Self-adhesive cement RX offers a valid alternative to multistep resin-based luting composite with respect to marginal adaptation to dentin and fracture resistance. The latter is also influenced by occlusal morphology, necessitating careful monitoring of occlusal contacts.
Clin Oral Investig. 2009 May 9. [Epub ahead of print]
Shear bond strength of self-adhesive resins compared to resin cements with etch and rinse adhesives to enamel and dentin in vitro.
Lührs AK, Guhr S, Günay H, Geurtsen W.
Department of Conservative Dentistry, Periodontology and Preventive Dentistry, Hannover Medical School, OE 7740, Carl-Neuberg-Str. 1, 30625, Hannover, Germany, Luehrs.Anne-Katrin@mh-hannover.de.
Self-adhesive resin cements should ease the placement of dental restorations. The purpose of this study was to evaluate their shear bond strength to enamel and dentin. Sixty molars were randomly assigned to 12 test groups (each n = 10), and the approximal surfaces were ground flat to get an enamel and dentin surface with a diameter of at least 4 mm. Ceramic specimens were bonded to the surfaces with either Variolink/Syntac Classic (VSC), Panavia F2.0 (PAF), RelyX Unicem (RLX), Maxcem Elite (MCE), iCem (IC), or an experimental self-adhesive resin cement (EXP). The shear bond strength (crosshead speed: 1 mm/min) was measured after 24-h storage in NaCl (37 degrees C). The fracture modes were determined with a stereomicroscope (magnification, 8-50-fold). VSC had the highest shear bond strength within the enamel groups (42.9 +/- 9 MPa) and IC the lowest (10.5 +/- 4.2 MPa, p < 0.001). The highest dentin shear bond strength was determined for VSC (39.2 +/- 8.9 MPa, p < 0.001) and the lowest for EXP (7.8 +/- 3.9 MPa, p < 0.001). Self-adhesive resin cements fractured mainly between resin and enamel or dentin. The shear bond strength of self-adhesive resin cements was inferior compared to conventional composite resin cements.
Surface modification for enhanced silanation of zirconia ceramics.
Piascik JR, Swift EJ, Thompson JY, Grego S, Stoner BR.
RTI International, Research Triangle Park, NC, USA; Department of Operative Dentistry, University of North Carolina, Chapel Hill, NC, USA.
OBJECTIVE: The overall goal of this research was to develop a practical method to chemically modify the surface of high strength dental ceramics (i.e. zirconia) to facilitate viable, robust adhesive bonding using commercially available silanes and resin cements. METHODS: Investigation focused on a novel approach to surface functionalize zirconia with a Si(x)O(y) “seed” layer that would promote chemical bonding with traditional silanes. ProCAD and ZirCAD blocks were bonded to a dimensionally similar composite block using standard techniques designed for silica-containing materials (silane and resin cement). ZirCAD blocks were treated with SiCl(4) by vapor deposition under two different conditions prior to bonding. Microtensile bars were prepared and subjected to tensile forces at a crosshead speed of 1mm/min scanning electron microscopy was used to analyze fracture surfaces and determine failure mode; either composite cohesive failure (partial or complete cohesive failure within composite) or adhesive failure (partial or complete adhesive failure). RESULTS: Peak stress values were analyzed using single-factor ANOVA (p<0.05). Microtensile testing results revealed that zirconia with a surface treatment of 2.6nm Si(x)O(y) thick “seed” layer was similar in strength to the porcelain group (control). Analysis of failure modes indicated the above groups displayed higher percentages of in-composite failures. Other groups tested had lower strength values and displayed adhesive failure characteristics. CONCLUSION: Mechanical data support that utilizing a gas-phase chloro-silane pretreatment to deposit ultra-thin silica-like seed layers can improve adhesion to zirconia using traditional silanation and bonding techniques. This technology could have clinical impact on how high strength dental materials are used today.
Oper Dent. 2009 Mar-Apr;34(2):157-65.
Effect of 2% chlorhexidine digluconate on the bond strength to normal versus caries-affected dentin.
Komori PC, Pashley DH, Tjäderhane L, Breschi L, Mazzoni A, de Goes MF, Wang L, Carrilho MR.
Department of Restorative Dentistry, Dental Materials, Piracicaba School of Dentistry, University of Campinas, Brazil.
This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acid-etched, rinsed and air-dried. In the control groups, the dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or two-step (Single Bond 2-SB) etch-and-rinse adhesive. In the experimental groups, the dentin was rehydrated with 2% CHX (60 seconds), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. The specimens were prepared for microtensile bond testing in accordance with the non-trimming technique, then tested either immediately or after six-months storage in artificial saliva. The data were analyzed by ANOVA/Bonferroni tests (alpha = 0.05). CHX did not affect the immediate bond strength to ND or CAD (p > 0.05). CHX treatment significantly lowered the loss of bond strength after six months as seen in the control bonds for ND (p < 0.05), but it did not alter the bond strength of CAD (p > 0.05). The application of MP on CHX-treated ND or CAD produced bonds that did not change over six months of storage.
J Dent. 2009 Mar 30.
Bonding potential of self-adhesive luting agents used at different temperatures to lute composite onlays.
Cantoro A, Goracci C, Carvalho CA, Coniglio I, Ferrari M.
Department of Dental Materials and Fixed Prosthodontics, University of Siena, Policlinico ‘Le Scotte’, viale Bracci, Siena 53100, Italy.
OBJECTIVES: To assess whether the bonding potential to dentin of self-adhesive resin cements was affected by their pre-cure temperature. METHODS: Composite overlays (Paradigm MZ100, 3M ESPE) were luted on 100 extracted molars with G-Cem (GC Corp.), BisCem (Bisco), Multilink Sprint (Ivoclar Vivadent), SAC-A (Kuraray Co.), XP Bond/Calibra (Detrey Dentsply). The cements were used at pre-cure temperatures that recur in their handling (4 degrees C refrigerator, 24 degrees C room and 37 degrees C intraoral), as well as following pre-heating up to 60 degrees C. Microtensile bond strengths to dentin were measured and compared with statistical tests. Scanning electron microscope observations of cement-dentin interfaces were performed. RESULTS: The bond strength of G-Cem and Calibra was not significantly affected by temperature changes from refrigerator storage to intraoral application. At any assessed pre-cure temperature the total-etch luting agent Calibra achieved a significantly stronger adhesion than the auto-adhesive cements. Limited to null adhesion was yielded by BisCem and SAC-A. The procedure of 60 degrees C pre-heating, proposed in previous studies for restorative resin composites, was of no use for the tested luting agents. Only the total-etch luting agent Calibra developed a distinct hybrid layer. The self-adhesive cements exhibited a more superficial interaction with dentin. CONCLUSIONS: Regardless of the pre-cure temperature, the bonding potential of the self-adhesive resin cements was inferior to that of the total-etch luting agent tested as control. The adhesive properties of the BisCem and SAC-A were extremely scarce.
J Dent. 2009 Mar 30. ]
Bonding potential of self-adhesive luting agents used at different temperatures to lute composite onlays.
Cantoro A, Goracci C, Carvalho CA, Coniglio I, Ferrari M.
Department of Dental Materials and Fixed Prosthodontics, University of Siena, Policlinico ‘Le Scotte’, viale Bracci, Siena 53100, Italy.
OBJECTIVES: To assess whether the bonding potential to dentin of self-adhesive resin cements was affected by their pre-cure temperature. METHODS: Composite overlays (Paradigm MZ100, 3M ESPE) were luted on 100 extracted molars with G-Cem (GC Corp.), BisCem (Bisco), Multilink Sprint (Ivoclar Vivadent), SAC-A (Kuraray Co.), XP Bond/Calibra (Detrey Dentsply). The cements were used at pre-cure temperatures that recur in their handling (4 degrees C refrigerator, 24 degrees C room and 37 degrees C intraoral), as well as following pre-heating up to 60 degrees C. Microtensile bond strengths to dentin were measured and compared with statistical tests. Scanning electron microscope observations of cement-dentin interfaces were performed. RESULTS: The bond strength of G-Cem and Calibra was not significantly affected by temperature changes from refrigerator storage to intraoral application. At any assessed pre-cure temperature the total-etch luting agent Calibra achieved a significantly stronger adhesion than the auto-adhesive cements. Limited to null adhesion was yielded by BisCem and SAC-A. The procedure of 60 degrees C pre-heating, proposed in previous studies for restorative resin composites, was of no use for the tested luting agents. Only the total-etch luting agent Calibra developed a distinct hybrid layer. The self-adhesive cements exhibited a more superficial interaction with dentin. CONCLUSIONS: Regardless of the pre-cure temperature, the bonding potential of the self-adhesive resin cements was inferior to that of the total-etch luting agent tested as control. The adhesive properties of the BisCem and SAC-A were extremely scarce.
J Biomed Mater Res B Appl Biomater. 2009 Mar 11.
Antibacterial activity and bonding ability of an adhesive incorporating an antibacterial monomer DMAE-CB.
Xiao YH, Ma S, Chen JH, Chai ZG, Li F, Wang YJ.
Department of Stomatology, Kunming General Hospital of PLA, Kunming 650032, China.
This study evaluated the antibacterial effect and microtensile bond strength of a resin-based adhesive containing an antibacterial monomer DMAE-CB (methacryloxylethyl cetyl dimethyl ammonium chloride). Cured specimens of 1, 2, and 3% DMAE-CB-containing Single Bond 2 (crosslinking monomer: Bis-GMA, dimethacrylates; functional monomer: HEMA) were prepared, and their antibacterial effects on Streptococcus mutans ATCC 25175 were investigated. Antibacterial property after 0, 30, 90, and 180 days of aging was also tested. Bonding ability of the experimental adhesive incorporating 3% DMAE-CB was evaluated by microtensile bond strength test. The cured experimental adhesive exhibited an inhibitory effect on S. mutans growth, and the adhesive containing 3% DMAE-CB showed higher antibacterial efficiency compared with those incorporating 1 or 2% anibacterial monomer. Antibacterial activities of the specimens lasted for at least 180 days. Microtensile bond strength test revealed that the bonding ability of the experimental adhesive was not significantly adversely affected by the incorporation of DMAE-CB. Therefore, dental adhesives with strong and long-lasting bacteriostatic property could be achieved by incorporating DMAE-CB without negatively influencing bonding ability. (c) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009.
J Dent Res. 2009 Feb;88(2):146-51.
Durability of resin-dentin bonds to water- vs. ethanol-saturated dentin.
Hosaka K, Nishitani Y, Tagami J, Yoshiyama M, Brackett WW, Agee KA, Tay FR, Pashley DH.
Cariology and Operative Dentistry, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
Higher 24-hour resin-dentin bond strengths are created when ethanol is used to replace water during wet bonding. This in vitro study examined if ethanol-wet-bonding can increase the durability of resin-dentin bonds over longer times. Five increasingly hydrophilic experimental resin blends were bonded to acid-etched dentin saturated with water or ethanol. Following composite build-ups, the teeth were reduced into beams for 24-hour microtensile bond strength evaluation, and for water-aging at 37 degrees C for 3, 6, or 12 months before additional bond strength measurements. Although most bonds made to water-saturated dentin did not change over time, those made to ethanol-saturated dentin exhibited higher bond strengths, and none of them fell over time. Decreased collagen fibrillar diameter and increased interfibrillar spacing were seen in hybrid layers created with ethanol-wet-bonding. Increases in bond strength and durability in ethanol-wet-bonding may be due to higher resin uptake and better resin sealing of the collagen matrix, thereby minimizing endogenous collagenolytic activities.
Evaluation of the mechanical properties of dental adhesives and glass-ionomer cements.
Magni E, Ferrari M, Hickel R, Ilie N.
Department of Fixed Prosthodontics and Dental Materials, University of Siena, Policlinico “Le Scotte”, Viale Bracci, 53100, Siena, Italy, elisamagni@hotmail.com.
Adhesives and lining/base materials should relieve the stresses concentrated at the tooth/restoration interface. The study aimed at comparing the mechanical properties of eight adhesives and six glass-ionomer cements (GICs). The adhesives were applied on dentin disks, whereas 2 mm x 3 mm x 2 mm GICs specimens were prepared in a teflon mold. Vicker’s hardness (VH), elastic modulus (E), creep (Cr) and elastic work (We/Wtot) were measured with a micro hardness indenter. One-way ANOVA and Tukey’s test were used to compare the mechanical properties within each materials’ type and among the materials’ classes. Enamel and dentin were used as references. Significant differences were detected within each materials’ type and among the materials’ classes and enamel and dentin. GICs were superior to adhesives in VH and E and showed a VH similar to dentin. GICs presented mechanical properties more similar to enamel and dentin than adhesives.
Acta Odontol Scand. 2009 Feb 23:1-7. [Epub ahead of print]
Streptococcal adhesion to various luting systems and the role of mixing errors.
Buergers R, Hahnel S, Reischl U, Mueller R, Rosentritt M, Handel G, Behr M.
Department of Prosthetic Dentistry, University Medical Center Regensburg, Germany.
Objective. This study aims at ranking various luting systems according to their susceptibility to adhering Streptococcus mutans and at evaluating the influence of incongruent mixing ratios on adhesion quantities. Material and Methods. Circular specimens measuring 8 mm in diameter were made of nine widely used dental cements-three of them mixed in different ratios-and then incubated with S. mutans. Adhering streptococci were quantified using a biofluorometric assay in combination with an automated plate reader for cell quantification. Surface roughness (R(a)) was determined by perthometer measurements. Results. Meron plus revealed the highest R(a) (0.90 microm) and glass the lowest R(a) (<0.01 microm). In regular cement mixtures, the highest mean fluorescence intensities indicated the presence of many viable bacteria [Meron Plus (35,533 relative fluorescence units (rfu)), Maxcem (13,374 rfu), and Panavia F 2.0 (11,701 rfu)]. Moderate fluorescence intensities were found in Harvard (4,171 rfu), Ketac cem (3,766 rfu), Durelon (3,276 rfu), Calibra (3,259), Rely X Unicem (4,358 rfu), and Bifix SE (3,102 rfu). A medium correlation between R(a) and S. mutans adhesion was found. Changes in regular cement proportions (powder/liquid and base/catalyst, respectively) had a significant influence on relative fluorescence intensities, which linearly increased with a higher proportion of liquid in Harvard and with a higher proportion of catalyst in Calibra and Maxcem. Conclusions. Various luting systems revealed considerable differences in their potential to adhere S. mutans. Variations from recommended cement proportions led to significant changes in the amount of adhering streptococci.
J Indian Soc Pedod Prev Dent. 2008;26 Suppl 3:S109-13.
Effect of glutaraldehyde and ferric sulfate on shear bond strength of adhesives to primary dentin.
Department of Pedodontics and Preventive Dentistry, Bapuji Dental College and Hospital, Davangere, Karnataka, India. attiguppeprabhakar@yahoo.com
AIM: The present study was undertaken to evaluate the effect of alternative pulpotomy agents such as glutaraldehyde and ferric sulfate on the shear bond strength of self-etch adhesive systems to dentin of primary teeth. MATERIALS AND METHODS: Eighty human primary molar teeth were sectioned in a mesiodistal direction and divided into experimental and control groups. Lingual dentin specimens in experimental groups were treated with glutaraldehyde and ferric sulfate. Buccal surfaces soaked in water served as control group. Each group was then divided into two groups based on the adhesive system used: Clearfil SE Bond and Adper Prompt L-Pop. A teflon mold was used to build the composite (Filtek Z-250) cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. The failure mode analysis was performed with a Scanning Electron Microscope (SEM). RESULTS: The results revealed that glutaraldehyde and ferric sulfate significantly reduced the shear bond strength of the tested adhesive systems to primary dentin. Clearfil SE Bond showed much higher shear bond strength than Adper Prompt L Pop to primary dentin. SEM analysis revealed a predominant cohesive failure mode for both adhesive systems. CONCLUSION: This study revealed that the pulpotomy medicaments glutaraldehyde and ferric sulfate adversely affected the bonding of self-etch adhesive systems to primary dentin.
Oper Dent. 2009 Jan-Feb;34(1):93-101.
Influence of oversized dowel space preparation on the bond strengths of FRC posts.
Schmage P, Pfeiffer P, Pinto E, Platzer U, Nergiz I.
School of Dental and Oral Medicine, Department of Restorative and Preventive Dentistry, University of Hamburg, Hamburg, Germany.
This study compared the bond strengths of fiber-reinforced composite (FRC) posts luted into oversized dowel spaces with FRC posts luted into precisely fitting dowel spaces using five different resin cements or build-up composites. The hypotheses examined were that bond strength does not present vast variations according to the width of the gap between the root canal and post and that bond strength increases for FRC posts luted with build-up composites compared with FRC posts luted with resin cements. Dowel space preparations (ER post-restoring system, 12 mm in length) were performed on 100 human anterior teeth up to ISO 90 and ISO 110 of 50 roots each. FRC posts, all ISO size 90, were inserted into the precisely fitting as well as into the oversized dowel spaces (n = 10) using five composite materials (Calibra, Multicore Flow, Rely X Unicem; resin cements and Build-It, Rebilda DC; build-up composites). The manufacturers’ instructions of the composite materials were strictly followed except for Rebilda DC, which was used with Adhese for dentin bonding. Following water storage (37 degrees C, 24 hours) and thermocycling (5000 cycles, 5 degrees C-55 degrees C, 30 seconds) tensile strength testing was performed and fracture modes were assessed using SEM. Data were analyzed statistically (one-way and two-way ANOVA, Bonferroni/Dunn correction, alpha < 0.05). The retentive bond strengths of FRC posts in oversized dowel spaces decreased significantly for all luting composites except for Rebilda DC, compared with the respective groups with precise fitting (p < 0.011). Yet, the bond strengths of RelyX Unicem (454 N +/- 64 N), Build-It (422 N +/- 43 N) and Calibra (408 N +/- 50 N) showed significantly higher values for the precisely fitting posts than Rebilda DC (267 N +/- 54 N). RelyX Unicem revealed significantly higher values than Multicore Flow (296 N +/- 73 N). The bond strengths of FRC posts in oversized dowel spaces varied from 301 N +/- 78 N for Build-It to 152 N +/- 37 N for Calibra. The values of Build-It were significantly higher compared with Calibra, Multicore Flow (180 N +/- 47 N) and Rebilda DC (186 N +/- 52 N), as well as those of RelyX Unicem (256 N +/- 115 N) were significantly higher than Calibra. Fracture modes were shown to be mainly adhesive at the post surface or cohesive for precisely fitting posts and to occur between post and composite except for RelyX Unicem with cohesive fractures for the oversized dowel spaces. The build-up composite Build-It showed superior bond strengths in oversized canals, which were still not as high as those of posts in precisely fitting dowel spaces using common resin cements.
J Adhes Dent. 2008 Dec;10(6):431-40.
Effect of caries-affected dentin hardness on the shear bond strength of current adhesives.
Wei S, Sadr A, Shimada Y, Tagami J.
Department of Restorative Sciences, Graduate school, Tokyo Medical and Dental University, Tokyo, Japan. yygcf617@yahoo.co.jp
PURPOSE: The aim of this study was to evaluate the microshear bond strength of three current adhesives to normal and caries-affected dentin, and to examine the correlation between dentin nanoindentation hardness and bond strength. MATERIALS AND METHODS: Nanoindentation hardness of dentin and microshear bond strength of Clearfil SE Bond, Clerafil Tri-S Bond (Kuraray Medical) and Single Bond (3M ESPE) were measured on caries-affected and normal dentin. Modes of fracture for the bonding tests and the resin/dentin interfaces were observed using SEM. Data were analyzed at a statistical significance level of p < 0.05. RESULTS: Significantly lower hardness values were recorded for caries-affected dentin compared to normal dentin. Two-way ANOVA showed that bonding material, type of dentin, and the interactions of these two factors had significant effects on bond strength. A significant correlation was found between dentin hardness and microshear bond strength. However, ANCOVA analysis revealed that the effect of dentin type was not only due to the mechanical properties of dentin. One-way ANOVA with Tukey’s HSD test revealed that the mean bond strength of normal dentin with Tri-S Bond was significantly lower than that with SE Bond and Single Bond; however, bond strengths to caries-affected dentin showed no significant difference between the three adhesives. CONCLUSION: All three adhesives showed lower bond strength to caries-affected dentin than to normal dentin. The differences between adhesives were not significant with caries-affected dentin as the bonding substrate. Dentin mechanical properties are not the only factors responsible for lower bond strength to caries-affected dentin.
J Adhes Dent. 2008 Dec;10(6):423-9.
Comparison of bonding performance of self-etching and etch-and-rinse adhesives on human dentin using reliability analysis.
Bradna P, Vrbova R, Dudek M, Roubickova A, Housova D.
Institute of Dental Research, 1st Faculty of Medicine, Charles University, General Faculty Hospital in Prague, Czech Republic. bradna@vus.cz
PURPOSE: To estimate the in vitro reliability of typical self-etching and etch-and-rinse adhesives of various application protocols. MATERIALS AND METHODS: The following adhesives were applied on flat dentin surfaces of extracted human teeth (n = 223): self-etching two-step adhesives: AdheSE (AH), Clearfil SE Bond (CL), OptiBond SE (OS); one-step adhesives: Adper Prompt L-Pop (ADP), Adper Prompt (AD), and Xeno III (XE); all-in-one adhesive: iBond (IB); etch-and-rinse three-step adhesives: OptiBond FL (OF), two-step Gluma Comfort Bond (G), Excite (E) and Prime & Bond NT (PB). Composite buildups were prepared using a microhybrid composite, Opticor New. Shear bond strength was determined after 24 h of storage at 37 degrees C in distilled water. The results were analyzed with a nested ANOVA (adhesive, type of adhesive) followed by the Fisher post-hoc tests of group homogeneity at alpha = 0.05. A two-parameter Weibull distribution was used to calculate the critical shear bond strength corresponding to 5% probability of failure as a measure of system reliability. RESULTS: ANOVA revealed a significant decrease (p < 0.001) in the mean shear bond strength as follows: AH=CL=OS=G=E=OF>AD=IB=XE>PB=ADP, but no significant difference (p > 0.48) between the etch-and-rinse and self-etching adhesives. The corresponding characteristic bond strength of Weibull distribution ranged between 24.1 and 12.1 MPa, Weibull modulus between 8.3 and 2.1, and the critical shear bond strength varied from 16.0 to 3.0 MPa. CONCLUSION: Pronounced differences in the critical shear bond strength suggest reliability variations in the adhesive systems tested, which originate from chemical composition rather than type of adhesive.
J Dent. 2009 Jan 28. [Epub ahead of print]
Effects of a dental adhesive incorporating antibacterial monomer on the growth, adherence and membrane integrity of Streptococcus mutans.
Li F, Chen J, Chai Z, Zhang L, Xiao Y, Fang M, Ma S.
Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Changle Xi Road 145, Xi’an, 710032, China.
OBJECTIVES: This study was attempted to incorporate an antibacterial monomer, methacryloxylethyl cetyl dimethyl ammonium chloride (DMAE-CB), into a commercial dental adhesive and to evaluate the antibacterial activity of the DMAE-CB-incorporated adhesive after being cured against Streptococcus mutans. METHODS: DMAE-CB was incorporated at 3% (w/v) into a clinically used dental adhesive, Single Bond 2. Single Bond 2 without DMAE-CB was served as a negative control; Clearfil Protect Bond, containing an intensively researched antibacterial monomer MDPB, was enrolled as a positive control. The effects of the cured adhesives and their eluents on the growth of S. mutans were determined by film contact test and absorbance measurement, respectively. The effects of the cured adhesives on the adherence and membrane integrity of S. mutans were investigated using confocal laser scanning microscopy (CLSM) in conjunction with fluorescent indicators. RESULTS: Compared with negative control, the cured DMAE-CB-incorporated dental adhesive and positive control were found to exhibit inhibitory effect on the growth of S. mutans (P<0.05), whereas their eluents did not show detectable antibacterial activity. Moreover, the fluorescence analysis of CLSM images demonstrated that the cured DMAE-CB-incorporated adhesive and positive control could hamper the adherence of S. mutans and exert detrimental effect on bacterial membrane integrity (P<0.05). CONCLUSIONS: The incorporation of DMAE-CB can render dental adhesive with contact antibacterial activity after polymerization via influencing the growth, adherence and membrane integrity of S. mutans.
Eur J Prosthodont Restor Dent. 2008 Dec;16(4):171-6.
Bonding of adhesive resin luting agents to metal and amalgam.
Osman SA, McCabe JF, Walls AW.
School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.
The shear bond strength of three adhesives, Panavia 21, Superbond, All Bond C&B Cement, and a dual cure resin (Variolink), to Ni-Cr-Be (Rexillium III), Midigold (Type III gold) and Amalgam (Sybraloy) were determined. Fifteen samples were prepared using 800 grit abrasive papers for Ni-Cr and Midi-Gold, and 100 grit papers for amalgam. Ni-Cr-Be and Midi-Gold samples were sandblasted for 30 s and steam cleaned for 10 s. The adhesives were bonded to the samples using gelatine capsules and were matured for 24 h in water at 37 degrees C. The samples were debonded in shear using an Instron at a cross-head speed of 1 mm/min. The data was analysed using ANOVA and a Tukey test. The bond strength of Superbond to both metal alloys was significantly higher (P<0.05) than any of the materials tested, with the exception Panavia 21 to gold. The bond strength of All Bond C&B cement had shown to be not significant difference from those of Panavia 21 and Variolink, when bonded to Rexillium and Midi-Gold, respectively. The bond strength of All Bond C&B Cement to amalgam was significantly greater (P<0.05) than those of the other materials tested. The shear bond strength to gold showed lower bonding for all adhesives when compared with Rexillium (P<.001). The ranking of bond strength to both alloys was as follows: Superbond>Panavia 21>All Bond C&B>Variolink. The nature of substrate to be used for bonding and the adhesive material itself are important factors in bonding which can be achieved between cast metals and prepared teeth with amalgam filling. Superbond should be successful as an adhesive for the attachment of all substrates tested, with the possible exception of amalgam, for which All Bond C&B Cement gives the best result.
Eur J Prosthodont Restor Dent. 2008 Dec;16(4):166-70.
Bonding of crown and bridge adhesive resins to dentine.
Osman SA, McCabe JF, Walls AW.
School of Dental Sciences, Newcastle University, Newcastle upon Tyne, UK.
The shear bond strength of three adhesives, Panavia 21, Superbond, All Bond C&B Cement, and Variolink (a dual cure resin) to various dentine depths were determined. Fifteen human fully erupted permanent first and second molars were wet ground using 500 and then 800 grit abrasive papers to expose the superficial, middle and the deep dentine, for each adhesive tested. Five samples were prepared for each dentine depth. The adhesives were bonded to the samples using gelatine capsules and were matured for 24 h in water at 37 degrees C. The samples were debonded in shear using tensile testing machine at a cross-head speed of 1 mm/min. The data were analysed using ANOVA and the Tukey test. The fracture surfaces were examined by optical microscopy. The bond strength of Superbond to dentine was significantly higher (P<0.05) than any of the materials tested. The bond strength of all materials tested was shown to be affected by dentine depth, except for Superbond. Fractured dentine specimens showed that the samples of Superbond are almost cohesive (>90%), and the samples of other adhesives are mostly adhesive (>70%). These results confirm that Superbond is capable of forming a bond at various dentine depths.
J Am Dent Assoc. 2009 Jan;140(1):28-37.
An eight-year clinical evaluation of filled and unfilled one-bottle dental adhesives.
Ritter AV, Swift EJ Jr, Heymann HO, Sturdevant JR, Wilder AD Jr.
BACKGROUND: The strategies for accomplishing resin adhesion to dentin involve surface conditioning, priming and bonding. One-bottle adhesives combine the priming and bonding functions in a single solution. In this study,the authors compared the eight-year clinical performance of two one-bottle adhesives made by different manufacturers. METHODS: The authors placed a total of 99 Class V restorations using either a filled, ethanol-based adhesive (OptiBond Solo [OS], SDS Kerr, Orange, Calif.) or an unfilled, acetone-based adhesive (Prime & Bond 2.1 [PB] Dentsply Caulk, Milford, Del.) and a hybrid resin-based composite in 33 subjects with noncarious cervical lesions. The authors did not bevel the enamel margins and used no mechanical retention. They evaluated the restorations at baseline and for as long as eight years after placement using modified U.S. Public Health Service criteria. They analyzed differences between groups using appropriate statistical tests. RESULTS: The authors examined 56 restorations after eight years and found retention rates of 69 percent for OS and 59 percent for PB. These rates did not differ statistically (P = .449) and were not significantly affected by subject or lesion characteristics. The authors noted marginal discoloration on 55 percent of the retained OS restorations and on 31 percent of the retained PB restorations, but they detected no secondary caries around any restoration. They noted poor anatomical form and poor marginal adaptation in 15 percent and 40 percent of the retained OS restorations, respectively. CONCLUSIONS: The performance of both adhesives was good during this eight-year clinical trial. The filled, ethanol-based adhesive OS demonstrated slightly better bond durability than did the unfilled, acetone-based adhesive PB, but the difference between the two materials was not statistically significant. CLINICAL IMPLICATIONS: Despite a high incidence of marginal discoloration, the one-bottle adhesives evaluated in this study provided good clinical retention of Class V restorations without mechanical retention. When the materials are used properly, restorations are retained at an acceptable rate through at least eight years of clinical service.
Dent Mater. 2008 Dec 24. [Epub ahead of print]
Effects of residual ethanol on the rate and degree of conversion of five experimental resins.
Cadenaro M, Breschi L, Rueggeberg FA, Suchko M, Grodin E, Agee K, Di Lenarda R, Tay FR, Pashley DH.
Department of Biomedicine, Unit of Dental Sciences and Biomaterials, University of Trieste, Italy.
OBJECTIVES: This study examined the extent of ethanol retention in five comonomer blends of experimental methacrylate-based dental adhesives, containing (10, 20, or 30wt.%) ethanol, after solvent evaporation, as well as observing the effect of residual ethanol and exposure duration on degree of conversion (DC). The null hypothesis that was tested was that residual, unevaporated ethanol has no effect on the rate or extent of DC of polymerized adhesive resins. METHODS: A known mass of each mixture was placed in glass wells and evaporated for 60s. The mass of the mixtures before and after evaporation was measured, allowing calculation of the gravimetric ethanol loss/retention. RESULTS: The concentration of retained ethanol increased significantly with ethanol concentration (p<0.01): 1.1-1.9mole/L for 10% ethanol/90% comonomers, 2.2-3.5 mole/L for 20% ethanol, and 2.6-3.7mole/L for 30% ethanol/70% comonomers. As ethanol is evaporated from solvated comonomer mixtures, the molar concentration of comonomers increases, reducing the vapor pressure of the remaining ethanol. Thus, the fractional loss of ethanol solvent decreases as the comonomer concentration increases. The DC of 10, 20, and 30wt.% ethanol blends increased with ethanol concentration in four of the five experimental resins (p<0.05), increasing by 30-45% when 10 or 20wt.% ethanol was added to neat resins, regardless of exposure duration. Depending on the resin system, inclusion of 30% ethanol lowered DC at 20s but increased DC after 40-60s of light exposure. SIGNIFICANCE: Since 10 and 20wt.% ethanol-resin blends increased the DC of solvated resins by 30-45% over neat resins, the test null hypothesis is rejected. Even with prolonged evaporation, 4-9% residual ethanol concentration can remain in 90/10 (wt./wt.) comonomer-ethanol mixtures. This is thought to be because comonomers lower the vapor pressure of ethanol. This amount of residual ethanol facilitates DC but lowers the rate of polymerization.
J Prosthet Dent. 2009 Jan;101(1):29-38.
An in vitro evaluation of the long-term resin bond to a new densely sintered high-purity zirconium-oxide ceramic surface.
Phark JH, Duarte S Jr, Blatz M, Sadan A.
Department of Comprehensive Care, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio 44106-4905, USA. jin-ho.phark@case.edu
STATEMENT OF PROBLEM: Successful long-term bonding to zirconia ceramic remains a challenge, requiring special cements and surface roughening by airborne-particle abrasion, which might negatively affect the ceramic. PURPOSE: The purpose of this study was to evaluate the shear bond strength (SBS) of composite resin cylinders to a modified zirconia surface using different luting techniques after thermal cycling. MATERIAL AND METHODS: Composite resin (TPH3) cylinders with a diameter of 3 mm were bonded to zirconia ceramics (Procera Zirconia) with a modified surface (RZ) and a machined surface (MZ). Three different adhesive luting cements (Panavia F2.0, RelyX ARC, RelyX Unicem) in combination with and without airborne-particle abrasion (50-microm and 110-microm Al(2)O(3)) were used. RZ was bonded using all 3 cements with (50 mum) and without airborne-particle abrasion; with 110 microm, only Panavia F2.0 was used. MZ was bonded using only Panavia F2.0 with (50 microm, 110 microm) and without airborne-particle abrasion. SBS was tested in a universal testing machine (Instron) before and after 90 days of water storage and 20,000 thermal cycles (dwell time, 15 seconds). Statistical analysis was performed using a multifactorial ANOVA model with alpha=.05. RESULTS: Mean SBS ranged from 10.1 to 20.0 MPa after 3 days and from 0.16 to 14.8 MPa after thermal cycling. Thermal cycling decreased SBS significantly. Airborne-particle abrasion significantly decreased SBS to the modified surface, regardless of cements used. SBS to the modified zirconia surface was significantly higher than to the machined surface. CONCLUSIONS: SBS to the modified zirconia surface is higher than to airborne-particle-abraded, machined zirconia. Airborne-particle abrasion of the modified zirconia surface is not recommended.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 Jan;107(1):137-44.
An immunohistochemical evaluation of cell adhesion molecules in human dental pulp after tooth preparation and application of temporary luting cements.
Bagis B, Atilla P, Cakar N, Hasanreisoglu U.
Department of Prosthodontics, Faculty of Dentistry, Karadeniz Technical University, Trabzon, Turkey.
OBJECTIVE: The aim of this study was to determine if temporary luting cements used with provisional restorations alter the expression of cell adhesion molecules (CAMs) in human dental pulp. STUDY DESIGN: Twenty-five healthy human premolars and third molars scheduled to be extracted for orthodontic reasons were randomly assigned to 5 experimental groups. Group 1 included untreated teeth as negative control. In groups 2-5, provisional crowns were cemented to the prepared teeth with either eugenol-containing or eugenol-free temporary cement and extracted 24 or 48 h after the treatment. Expression ratio and staining intensity of CAMs, including E-selectin, P-selectin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and platelet endothelial cell adhesion molecule 1 (PECAM-1), was investigated in the pulp samples. The assessment of immunohistochemical reactions was performed by 2 independent observers using a semiquantitative scale. RESULTS: Significant reductions were recorded in the expression ratio and/or the staining intensity of E-selectin, ICAM-1, and VCAM-1 in samples removed 48 h after treatment with eugenol-containing cement compared with intact teeth. This reduction was significant only for ICAM-1 for 48-h eugenol-free samples. Moreover, the eugenol-free cement group indicated considerably higher E-selectin, ICAM-1, and VCAM-1 expression compared with the eugenol-containing group (P < .005) 48 h after the application. The PECAM-1 reactivity was similar for all of the experimental groups. CONCLUSION: Application of temporary luting cements after tooth preparation for full crown causes alterations in the expression of endothelial CAMs in the dental pulp.
J Biomed Mater Res B Appl Biomater. 2008 Dec 17. [Epub ahead of print]
Two-photon laser confocal microscopy of micropermeability of resin-dentin bonds made with water or ethanol wet bonding.
Sauro S, Watson TF, Mannocci F, Miyake K, Huffman BP, Tay FR, Pashley DH.
Dental Biomaterials Science, Biomimetics and Biophotonics, King’s College London Dental Institute at Guy’s, King’s College and St. Thomas’ Hospitals, London, United Kingdom.
This study evaluated the micropermeability of six etch-and-rinse adhesives bonded to dentin. There were two principal groups: wet bonding with water or wet bonding with absolute ethyl alcohol. After bonding and the creation of composite build-ups, the pulp chambers were filled with 0.1% lucifer yellow. The contents of the pulp chamber were kept under 20 cm H(2)O pressure to simulate pulpal pressure for 3 h. The specimens were vertically sectioned into multiple 0.5-mm thick slabs that were polished and then examined using a two-photon confocal laser scanning microscope (TPCLSM). The results showed that specimens bonded with adhesives using the water wet-bonding condition all showed tracer taken up uniformly by the hybrid layer. This uptake of fluorescent tracer into the hybrid layer was quantified by computer software. The most hydrophobic experimental resins showed the highest fluorescent tracer uptake (ca. 1800 +/- 160 arbitrary fluorescent units/std. surface area). The most hydrophilic experimental resins showed the lowest tracer uptake into water-saturated hybrid layers. When ethanol wet-bonding was used, significantly less fluorescent tracer was seen in hybrid layers. The most hydrophilic experimental resins and Single Bond Plus showed little micropermeability. Clearly, ethanol wet-bonding seals dentin significantly better than water-wet dentin regardless of the adhesive in etch-and-rinse systems. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009.
J Endod. 2009 Jan;35(1):121-4.
Bonding of resin-based sealers to root dentin.
Rahimi M, Jainaen A, Parashos P, Messer HH.
School of Dental Science, The University of Melbourne, Melbourne, Victoria, Australia.
This study compared the microshear bond strength of three resin-based sealers to root dentin and assessed whether sealer cements behave differently in thin and thick films. Extracted maxillary premolars were sectioned buccolingually, and 45 root halves were randomly allocated for microshear bond testing with the three resin sealers in thin and thick films. The microshear bond strength was then calculated in MPa. Failure modes were examined under light and scanning electron microscopy. Data were analyzed by using analysis of variance, with significance set at p < 0.05. Overall, the epoxy resin-based sealers had the highest microshear bond strength to root dentin compared with urethane dimethacrylate-based sealers (p < 0.001). Bond strengths for the thick sealer group were significantly higher than the thin sealer group (p < 0.001) and may reflect different patterns of behavior when the sealer is present as a thin layer.
SADJ. 2008 Sep;63(8):448-51.
Antibacterial properties of five bonding agents.
Brandt PD, Botha FS, de Wet FA.
Department of Odontology, School of Dentistry, University of Pretoria, South Africa. pbrandt@medic.up.ac.za
PURPOSE: This study compared antibacterial properties of five bonding agents with that of a control, Chlorhexidine (2.5%). Products evaluated were the self-etch primers (-P) and adhesives (-A) of Clearfil SE Bond (SE-P; SE-A) [Kuraray Dental], Clearfil Protect Bond (PB-P; PB-A) [Kuraray Dental], Optibond Solo Self-etch (OS-P; OS-A) [Kerr] and the one-bottle products, self-etch Clearfil Tri-S Bond (3S) [Kuraray Dental] and total-etch Adper Scotchbond 1 XT (XT) [3M ESPE]. METHODS: Spread plates of three different bacteria (Streptococcus mutans, Lactobacillus paracasei and Actinomyces naeslundii) were prepared on Casein-peptone-Soymeal-peptone Agar (CASO-Agar). Controls, Primers, Adhesives, and Primer & Adhesive combinations were placed on standardized, sterilized filtration paper or composite disks and then placed on the inoculated agar and incubated at 37 degrees C for 48 hours. Inhibition zones were measured and data was statistically analyzed using the Student t-test. An additional test was performed by which growth inhibiting of 1/10 and 1/100 dilutions of the test suspensions were measured spectrophotometrically as turbidity at 600 nm and expressed as percentage growth (%). RESULTS: Compared to the controls, the only cured product which produced significant inhibition was Scotchbond 1 XT (XT), and that for Actinomyces naeslundii only. The primer of Clearfil Protect Bond (PB-P) showed statistically significant growth inhibition for all three test bacteria, the primer of SE Bond (SE-P) had significant inhibitive properties against Streptoccocus mutans and Actinomyces naeslundii and the primer of Optibond Solo Self-etch (OS-P) inhibited growth of Actinomyces naeslundii significantly. CONCLUSIONS: The primers of Clearfil Protect Bond, Clearfil SE Bond, Optibond Solo Self-etch and the product Adper Scotchbond 1 XT may be beneficial in eliminating remaining bacteria after cavity preparation, but further research on a possible long-term antibacterial benefit of these products needs to be undertaken.
Oper Dent. 2008 Nov-Dec;33(6):651-7.
Long-term durability of one-step adhesive-composite systems to enamel and dentin.
Foxton RM, Melo L, Stone DG, Pilecki P, Sherriff M, Watson TF.
Division of Conservative Dentistry, King’s College London Dental Institute, Guy’s Tower, Guy’s Hospital, London Bridge, London. richard.foxton@kcl.ac.uk
This study evaluated the long-term durability of three one-step adhesive-composite systems to ground enamel and dentin. Twenty-seven teeth were randomly divided into three groups of nine. The first group had its crowns sectioned to expose superficial dentin, which was then ground with 600 grit SiC paper. One of three one-step adhesives: a trial bonding agent, OBF-2; i Bond or Adper Prompt L-Pop was applied to the dentin of three teeth and built-up with the corresponding resin composite (Estelite sigma, Venus or Filtek Supreme). The second group of nine teeth had their enamel approximal surfaces ground with wet 600-grit SiC paper, then one of the three one-step adhesives was applied and built-up with resin composite. The bonded specimens were sliced into 0.7 mm-thick slabs. After 24 hours and one year of water storage at 37 degrees C, the slabs were sectioned into beams for the microtensile bond strength test. Failure modes were observed using optical and electron scanning microscopy. The third group of nine teeth had approximal wedge-shaped cavities prepared above the CEJ into dentin. Two-to-three grains of rhodamine B were added to each of the three adhesives prior to restoring the cavities with resin composite. After 24 hours storage, the teeth were sectioned and their interfaces examined with a laser scanning confocal microscope. The bond strengths of the three adhesive-composite systems to both enamel and dentin significantly lessened after one year of water storage, however, there was no significant difference between the materials.
Eur J Oral Sci. 2008 Dec;116(6):571-8.
Sealing ability of occlusal resin composite restoration using four restorative procedures.
Banomyong D, Palamara JE, Messer HH, Burrow MF.
Restorative Dentistry Section, School of Dental Science, the University of Melbourne, Melbourne, Victoria, Australia.
The purpose of this work was to investigate fluid flow after restoration using four restorative procedures. Micro-gap, internal dye leakage, and micropermeability of bonded interfaces were also investigated. Each tooth was mounted, connected to a fluid flow-measuring device, and an occlusal cavity was prepared. Fluid flow after cavity preparation was recorded as the baseline measurement, and the cavity was restored using one of four restorative procedures: bonding with total-etch (Single Bond 2) or self-etch (Clearfil SE Bond) adhesives without lining; or lining with resin-modified glass-ionomer cement (GIC) (Fuji Lining LC) or conventional GIC (Fuji IX) and then bonding with the total-etch adhesive. Fluid flow was recorded after restoration and at specific time-points up to 6 months thereafter and recorded as a percentage. Micro-gap formation was analyzed using resin replicas and scanning electron microscopy. Internal leakage of 2% methylene blue dye was observed under a light microscope. In micro-permeability testing, fluorescent-dye penetration was investigated using confocal laser microscopy. None of the restorative procedures provided a perfectly sealed restoration. Glass-ionomer lining did not reduce fluid flow after restoration, and micro-gaps were frequently detected. The self-etch adhesive failed to provide a better seal than the total-etch adhesive, and even initial gap formation was rarely observed for the former. Penetration of methylene blue and fluorescent dyes was detected in most restorations.
Mutagenesis. 2008 Dec 1.
In vivo genotoxicity of dental bonding agents.
Arossi GA, Dihl RR, Lehmann M, Cunha KS, Reguly ML, de Andrade HH.
Laboratório da Toxicidade Genética (TOXIGEN), Programa de Pós-graduação em Genética e Toxicologia Aplicada (PPGGTA), Universidade Luterana do Brasil (ULBRA), Prédio 22, 4 degrees andar, Avenida Farroupilha, 8001, 92425-900, Canoas, RS, Brazil.
This in vivo study investigated the genotoxicity of two dental bonding agents: Adper Single Bond Plus and Prime&Bond 2.1. The somatic mutation and recombination test (SMART) in Drosophila melanogaster was applied to analyse their genotoxicity expressed as homologous mitotic recombination, as well as point and chromosomal mutation. SMART detects the loss of heterozygosity of marker genes expressed phenotypically on the fly’s wings. This fruit fly has extensive genetic homology to mammals, which makes it a suitable model organism for genotoxic investigations. Adper Single Bond Plus induced statistically significant increases in the frequency of total spots at the highest concentration tested, while Prime&Bond 2.1 was positive at all concentrations tested. The mechanistic basis underlying the genotoxicity of Adper Single Bond Plus relies on mitotic recombination alone, and was different from that of Prime&Bond 2.1, which showed evidence of the contribution of both recombination and mutational events. These findings indicate that both adhesives are inducers of toxic-genetic events, with the mitotic recombination being the main mechanism of action. The clinical significance of these observations has to be interpreted with data obtained in other bioassays.
Dent Mater J. 2008 Sep;27(5):660-5.
Effect of light intensity for adhesives on shear bond strength to dentin.
Department of Operative Dentistry, School of Dentistry, Niigata, The Nippon Dental University, 1-8 Hamaura-cho, Niigata, 951-8580, Japan. shinkaik@ngt.ndu.ac.jp
This study evaluated the effect of light intensity on the shear bond strength (SBS) of two self-etch adhesive systems: SI-R20401 (an experimental two-step) and Fluoro Bond Shake One (a commercial one-step bonding system). The adhesive systems were applied to the flat dentin surfaces of extracted human teeth according to manufacturers’ instructions. Light intensities used for the adhesive systems were 100, 300, and 500 mW/cm2. A resin composite paste was placed and polymerized for 40 seconds with 600 mW/cm2 of light intensity after each bonding procedure. Specimens were subjected to SBS test with a 1.0 mm/minute crosshead speed. Data were statistically analyzed using ANOVA, followed by Bonferroni post hoc test. Two-way ANOVA showed no significant differences in the effects of the adhesive system, light intensity for appliedadhesive, and the interaction between them. Based on the results and limitations of this study, it was concluded that light intensity showed no significant effects on the SBS of the two self-etch adhesive systems.
J Dent. 2008 Oct 14.
Dentin and enamel bond strengths of dual-cure composite luting agents used with dual-cure dental adhesives.
Ritter AV, Ghaname E, Pimenta LA.
Department of Operative Dentistry, UNC Chapel Hill, School of Dentistry, 441 Brauer Hall, CB#7450, Chapel Hill, NC 27599-7450, United States.
OBJECTIVE: The purpose of this in vitro study was to evaluate and compare dentin and enamel bond strengths obtained with dual-cure composite luting agents when used with dual-cure dental adhesives. METHODS: Human molars were ground flat to expose enamel (n=80) or dentin (n=80). Specimens in each substrate group were randomly assigned to eight treatment sub-groups, according to four adhesive-luting agent combinations and two test conditions (with or without thermocycling). Pre-polymerized composite resin posts (TPH Spectrum) were luted to either the enamel or dentin surfaces with one of the following adhesive-luting agent combinations: (1) Xeno IV Dual Cure (dual-cure self-etch adhesive) and Calibra (dual-cure luting agent); (2) Prime & Bond NT Dual Cure (dual-cure total-etch adhesive) and Calibra; (3) OptiBond All-in-One Dual Cure (dual-cure self-etch adhesive) and Nexus 2 Dual Syringe (dual-cure luting agent); (4) OptiBond Solo Plus Dual Cure (dual-cure total-etch adhesive) and Nexus 2 Dual Syringe. For each treatment sub-group, half the specimens (n=10) were tested after 24h storage in water at 37 degrees C, and the other half (n=10) were tested after thermocycling for 1800 cycles between water baths held at 5 and 55 degrees C, with a dwell time in each bath of 30s, and a transfer time of 10s. Bond strengths were measured in shear mode, and expressed in MPa. The fracture mode (adhesive, cohesive, mixed) was examined. Data were analyzed for statistical significance with a factorial ANOVA and post hoc tests. RESULTS: Mean enamel bond strengths ranged from 8.4MPa for non-thermocycled OptiBond All-in-One|Nexus 2 to 35.5MPa for non-thermocycled Prime & Bond NT|Calibra. Mean dentin bond strengths ranged from 14.5MPa for non-thermocycled OptiBond Solo Plus|Nexus 2 to 30.9MPa for thermocycled Xeno IV|Calibra. The fracture mode was predominantly adhesive for all groups. CONCLUSIONS: On enamel, the total-etch adhesives performed better than their self-etch counterparts, while in dentin, the opposite was found, i.e., the self-etch adhesives performed better than their total-etch counterparts. Thermocycling for 1800 cycles did not affect the SBS of the materials tested to dentin and enamel.
Acta Odontol Latinoam. 2008;21(1):29-33.
Film thickness of resin cements used with adhesive systems.
Zahra VN, Abate PF, Macchi RL.
Department of Dental Materials. School of Dentistry, University of Buenos Aires, Argentina. drvivian@hotmail.com
The final film thickness of a resin adhesive and a resin cement could be affected by previous polymerization of the adhesive systems on dentin surfaces. The aim of this work was to evaluate changes in the film thickness of dual resin based cements with their adhesives as a function of polymerization of the latter on dentin surfaces. The materials used were: RelyX ARC (R) + Single Bond (SB) and Variolink base (VB) and high (HV) or low (LV) viscosity catalyst + Syntac Classic (S) or Excite DSC (E); 56 human dentin discs and 56 composite resin discs (Z250). Dentin disc surfaces were treated with 35% phosphoric acid (except for S) and the adhesive system was either polymerized or not polymerized. A 0.05 ml increment of cement mixture was placed on the dentin disc and covered with the resin disc. A 25 N load was applied for ten minutes and then, the combined thickness was measured with a digital micrometer. Sample size (n) was 4 for each cement or condition. A two-way analysis of variance was performed with a level of significance of p < 0.05. The mean film thickness (and standard deviations) in microm, with and without previous polymerization of the adhesive layer, were: R+SB: 16.50 (2.64) and 17.00 (1.41); VB+S: 21.75 (5.37) and 62.25 (0.95); VB LV+S: 24.50 (3.87) and 72.75 (1.89); VB HV+S: 28.75 (8.46) and 93.00 (53.63); VB+E: 31.75 (8.38) and 42.75 (4.34); VB LV+E: 47.75 (2.50) and 45.75 (3.20); VB HV+E: 49.25 (25.50) and 45.75 (2.75). Significant differences (p < 0.01) were found for the cements and polymerization condition as well as for the interaction between them. Instructions regarding polymerization of the adhesive layer must be followed when adhesive systems are used in combination with dual polymerized resin based cements. Otherwise, final film thickness of the adhesive and the resin cement could be affected.
Am J Dent. 2008 Jun;21(3):148-52.
36-month clinical evaluation of two adhesives and microhybrid resin composites in Class I restorations.
Swift EJ Jr, Ritter AV, Heymann HO, Sturdevant JR, Wilder AD Jr.
Department of Operative Dentistry, University of North Carolina, Chapel Hill, NC 27599-7450, USA. ed_swift@dentistry.unc.edu
PURPOSE: To compare the clinical performance of a self-etching adhesive with that of a popular etch-and-rinse adhesive in Class I posterior composite restorations. METHODS: 60 Class I resin composite restorations (30 per group) were placed in matched pairs using either the self-etch adhesive Xeno III and the microhybrid resin composite Esthet-X or the etch-and-rinse adhesive OptiBond Solo Plus and Point 4 microhybrid resin composite. Subjects were interviewed via telephone 1 week after restoration placement to assess early post-operative sensitivity. In addition, the restorations were evaluated clinically for post-operative sensitivity, marginal quality, wear, and other characteristics immediately after placement and at 6, 12, 18, and 36 months from baseline. RESULTS: During the first week after placement, subjects reported that 23% of restorations in each group had post-operative sensitivity. Sensitivity decreased greatly with time, and differences between the two groups were never statistically significant. Marginal integrity and discoloration were similar for each group at each recall evaluation. Wear of both resin composites increased over time, but mean wear remained at less than 100 microm for each resin composite at 3 years.
Oper Dent. 2008 Jul-Aug;33(4):456-60.
Comparison of enamel and dentin microshear bond strengths of a two-step self-etching priming system with five all-in-one systems.
Burrow MF, Kitasako Y, Thomas CD, Tagami J.
School of Dental Science, The University of Melbourne, Victoria, Australia. mfburrow@unimelb.edu.au
Data on the adhesive strength of new all-in-one adhesives are still relatively limited. This study compared the microshear bond strengths of five recent all-in-one self-etching priming systems (G-Bond, One-Up Bond-F Plus, Clearfil S3 Bond, Adper Prompt L-Pop and Go!) with a widely used two-step self-etching priming system (Clearfil SE Bond). Human molars were sectioned and finished with 600-grit SiC paper. Both enamel and dentin were bonded using adhesives with a 0.7 mm bonding diameter. Bond strengths were tested using a microshear bond test method at a crosshead speed of 1 mm/minute. The mean bond strengths and standard deviations were calculated and analyzed using ANOVA and the Tukey’s HSD test. Results showed the two-step self-etching system had significantly higher bond strengths to dentin. However, for enamel bond strength, Clearfil SE Bond showed no statistical difference to G-Bond and Go!; however, all of the other materials were statistically lower. It is necessary to examine these new materials clinically to determine their efficacy.
Oper Dent. 2008 Jul-Aug;33(4):448-55.
Influence of Er,Cr:YSGG laser treatment on microtensile bond strength of adhesives to enamel.
Cardoso MV, De Munck J, Coutinho E, Ermis RB, Van Landuyt K, de Carvalho RC, Van Meerbeek B.
Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Leuven, Belgium.
The current trend towards minimum-intervention dentistry has introduced laser technology as an alternative technique for cavity preparation. This study assessed the null hypothesis that enamel prepared either by Er,Cr:YSGG laser or conventional diamond bur is equally receptive to adhesive procedures. The buccal and lingual surfaces of 35 sound human molars were prepared with Er,Cr:YSGG laser or a medium-grit diamond bur. One etch&rinse (OptiBond FL) and three self-etch adhesives (Adper Prompt L-Pop, Clearfil SE Bond and Clearfil S3 Bond) were applied on laser-irradiated and bur-cut enamel, followed by the application of a 5-6 mm build-up of Z100. The micro-tensile bond strength (microTBS) was determined after 24 hours of storage in water at 37 degrees C. Prepared enamel surfaces and failure patterns were evaluated using a stereomicroscope and a field-emission-gun scanning electron microscope (Feg-SEM). The pTBS to laser-irradiated enamel was significantly lower than to bur-cut enamel (p<0.05), with the exception of Clearfil S3 Bond, which bonded equally effectively to both substrates. The latter presented the highest microTBS on laser-irradiated enamel, though it was not statistically different from the microTBS of OptiBond FL. SEM analysis revealed significant morphological alterations of the laser-irradiated enamel surface, such as areas of melted and recrystalized hydroxyapatite and deep extensive micro-cracks. In conclusion, the bonding effectiveness of adhesives to laser-irradiated enamel depends not only on the structural substrate alterations induced by the laser, but also on the characteristics of the adhesive employed.
Dent Mater. 2008 Sep 29.
PMMA-grafted nanoclay as novel filler for dental adhesives.
Atai M, Solhi L, Nodehi A, Mirabedini SM, Kasraie S, Akbari K, Babanzadeh S.
Iran Polymer and Petrochemical Institute (IPPI), P.O. Box 14965/115, Tehran, Iran.
OBJECTIVE: The aim of this study was to investigate the benefits of incorporation of poly(methyl methacrylate)-grafted-nanoclay on the bond strength of an experimental one-bottle dentin bonding system. The effect of the modification on the stability of the nanoparticle dispersion in the dilute adhesive was also studied. MATERIALS AND METHODS: Poly(methyl methacrylate) was grafted onto the pristine Na-MMT nanoclay (Cloisite((R)) Na(+)) through the free radical polymerization of methyl methacrylate in an aqueous media in the presence of ammonium persulfate as initiator. A reactive surfactant (AMPS) was also used in the reaction recipe to provide active sites on the surface of the nanoclay. The grafting polymerization reaction was carried out at 70 degrees C. The PMMA-g-nanoclay was then coagulated in methanol and filtered. The resulting PMMA-g-nanoclay was characterized using FTIR, TGA, X-ray diffraction (XRD) and particle size distribution analysis. The modified nanoclay was added to an experimental dentin bonding system as filler and the morphology of the nanoclay layers in the adhesive matrix was studied using TEM and XRD. Shear bond strength of the adhesives containing different filler contents was tested on the caries-free extracted human premolar teeth. The mode of failure was studied by scanning electron microscopy. The stability of the nanoclay dispersion in the dilute adhesive was also studied using a separation analyzer. The results were then statistically analyzed and compared. RESULTS: The grafting of poly(methylmethacrylate) onto the nanoclay was confirmed and the results revealed a partially exfoliated structure for the PMMA-g-nanoclay. Incorporation of the modified nanoclay provided a dentin bonding system with higher shear bond strength. The dispersion stability of the modified nanoparticles in the dilute adhesive was also increased more than 40 times in comparison with the pristine nanoclay. SIGNIFICANCE: The grafting modification provided nanoclay particles with higher dispersion stability than pristine Na-MMT nanoclay in a dilute dentin bonding system. Incorporation of the modified nanoclay into the bonding system provided higher shear bond strength. The finding would be beneficial in producing nano-filler containing adhesive systems.
Am J Dent. 2008 Aug;21(4):223-8.
Hardness and elasticity of caries-affected and sound primary tooth dentin bonded with 4-META one-step self-etch adhesives.
Hosoya Y, Tay FR, Miyakoshi S, Pashley DH.
Department of Pediatric Dentistry, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1, Sakamoto, Nagasaki 852-8588, Japan. hosoya@nagasaki-u.ac.jp
PURPOSE: To evaluate the quality of the interface of sound and carious primary tooth dentin bonded with two 4-META one-step self-etch adhesives. METHODS: 12 sound and 12 carious primary molars were bonded with AQ Bond Plus (AQBP; Sun Medical) or Hybrid Bond (HB; Sun Medical) and restored with Clearfil Protect Liner F (Kuraray Medical Inc.). After 24 hours of water immersion, the teeth were sectioned and polished. Resin-dentin interfaces were measured with a nano-indentation tester and hardness and Young’s modulus were calculated. Data were analyzed using one-way or two-way ANOVA and Fisher’s PLSD test with alpha = 0.05. Resin-dentin interfaces were also observed with SEM and TEM. Ammoniacal silver nitrate was used as a tracer for TEM observation. RESULTS: Hardness and Young’s modulus of the interfacial dentin were significantly lower than the underlying intact dentin except for the carious-AQBP group. However, there was no significant difference of hardness and Young’s moduli of the interfacial dentin among all groups. TEM revealed extensive interfacial nanoleakage in sound dentin bonded with either AQBP or HB. For the carious teeth, nanoleakage was absent in the hybrid layers bonded with the two adhesives. However, extensive silver deposits were identified from the subsurface, porous caries-affected dentin.
J Endod. 2008 Oct;34(10):1202-6. Epub 2008 Aug 23.
Vasorelaxant effect of a self-etch adhesive system through calcium antagonistic action.
Basak F, Vural IM, Kaya E, Ulku C, Guven G, Cehreli SB, Cehreli ZC, Seyrek M, Yildiz O.
Department of Pediatric Dentistry, Center of Dental Sciences, Gulhane School of Medicine, Ankara, Turkey.
Etch-and-rinse adhesives can cause vasorelaxation via mechanisms occurring in the endothelium and smooth muscle, including the release of nitric oxide (NO). This effect might promote or aggravate bleeding if such adhesives are placed inadvertently on iatrogenic pulp microexposures. The present study assessed the vasoactive potential of a newer generation self-etch adhesive, Clearfil Protect Bond (CPB), on isolated rat aorta. Cumulative concentrations of the primer, bond, and mixture of CPB elicited concentration-dependent relaxation of phenylephrine-induced active tonus in the rat aorta, demonstrating that the tested self-etch adhesive can lead to vasorelaxation of pulp vessels that is mediated by Ca(2+) antagonistic effect. The vasorelaxant effect of CPB or its components was mediated neither via endothelium-dependent NO and prostanoid-dependent mechanisms nor by K(+) efflux through K(+) channels. Mechanical removal of the endothelium did not significantly alter the relaxation induced by CPB. Assuming these data can be extrapolated to the clinical situation, CPB, either in mixed form or by its components, can lead to vasorelaxation of pulp vessels that is mediated by a Ca(2+) antagonistic effect. If CPB is placed inadvertently on pulp microexposures during direct pulp capping, this effect might promote bleeding that might impair healing and, via plasma exatravasation, might compromise resin infiltration and polymerization.
Prague Med Rep. 2007;108(4):358-67.
Comparison of dentine-resin interface in total-etch and self-etching adhesives using electron microscopy.
Kukletová M, Halacková Z, Horký D, Matousek A, Gojisová E, Cihlár J.
Stomatological Clinic, Masaryk University, Medical Faculty, Brno, Czech Republic. martina.kukletova@fnusa.cz
The important condition for the adhesive bond between dentine and composite filling is the change of dentine property from hydrophilic to hydrophobic. Substances able to accomplish this change, dentinal adhesives, have undergone complex development. Recently, the so-called self-etching adhesives have been formulated. The aim of the present paper was to compare the structural pattern of dentin/resin interface after the application of dentinal adhesives used in total- and self-etching technique. Dentinal adhesives Single bond, Prime bond, Prompt-L-pop Adper, and Xeno III were used. The former two belong to the total etch technique, the latter two to the self-etching technique. The dentin/resin interface was studied in transmission (TEM) and scanning (SEM) electron microscope. In TEM sixteen teeth were investigated, each adhesive was applied in four teeth. Under SEM forty teeth were studied, each adhesive was applied in ten teeth. The obtained results demonstrated that all the dentine adhesives studied were able to penetrate into dentinal tubules and to form a hybrid layer with the demineralized intertubular and peritubular dentine. There was no substantial difference in morphology of the dentine/resin interface between the techniques studied. Our results suggest that the hybrid layer function of all four adhesives might be of the same quality.
Dent Mater J. 2008 Mar;27(2):266-72.
Effects of one-year storage in water on bond strength of self-etching adhesives to enamel and dentin.
Ansari ZJ, Sadr A, Moezizadeh M, Aminian R, Ghasemi A, Shimada Y, Tagami J, Ansari SJ, Moayedi S.
Department of Restorative Dentistry, Dental School, Shahid Beheshti University, M.C., Daneshjou Blvd, Evin, Tehran 19834, Iran.
The aim of this study was to compare the bond strengths of three self-etching materials during one year of storage. Clearfil SE Bond (SE), Clearfil Protect Bond (PB), and Clearfil Tri-S Bond (TS) were used for bonding to dentin and enamel according to manufacturer’s instructions. Microshear bond strength values were measured after 24 hours, six months, and one year. Two-way ANOVA showed that the interaction of material type and storage time was significant for dentin. At baseline, SE had the highest bond strength to dentin. There were no significant changes in bond strength for each material during the storage period, except for PB which showed increased bond strength to dentin after one year. All materials performed reliably after one year. However, the antibacterial and fluoride-releasing effects of PB would further contribute to the long-term clinical benefits of this material.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008 Jul;106(1):152-8.
Comparison of the sealing of different dentin bonding adhesives in root-end cavities: a bacterial leakage study.
Er K, Taşdemir T, Bayramoğlu G, Siso SH.
Department of Endodontics, School of Dentistry, Karadeniz Technical University, Trabzon, Turkey. kursater@ktu.edu.trp
OBJECTIVE: To compare the root-end sealing of the different dentin-bonding adhesives (DBAs) in root-end cavities using a bacterial leakage system. STUDY DESIGN: One hundred extracted single-rooted teeth were instrumented, and root-ends were resected and ultrasonically prepared. All teeth were then randomly assigned to 6 experimental groups (n = 15) and 2 control groups (positive and negative control; n = 5) for root-end filling with iBond (Heraeus Kulzer, Hanau, Germany), G-bond (GC Co., Tokyo, Japan), Xeno III Bond (Dentsply/Caulk, Milford, DE), AdheSe Bond (Ivoclar Vivadent, Schaa, Liechenstein), Clearfil Protect Bond (Kuraray, Osaka, Japan), or Clearfil Tri-S Bond (Kuraray). All preparations were further restored with a hybrid resin composite (Renew; Bisco, Schaumburg, IL). Nail varnish was applied to all external root surfaces to the level of the resected root-ends to prevent lateral microleakage. Samples were sterilized in an ethylene oxide sterilizer for 12 h. The apical 3-4 mm of the roots were immersed in brain-heart infusion culture medium with phenol red indicator within culture chambers. The coronal access of each specimen was inoculated every 48 h with a suspension of Enterococcus faecalis. Bacterial leakage was monitored every 24 h for 4 weeks. The data obtained were analyzed using a chi-squared test, with alpha = .05 as the level for statistical significance. RESULTS: All positive controls leaked within 24 h; none of the negative controls leaked. Under the conditions of the study, despite some variations, there were no statistically significant differences in rate of bacterial leakage among the experimental test materials at 1-4 weeks (P > .05). CONCLUSIONS: The type of DBA had no influence in the bacterial leakage of the root-end fillings.
Dent Mater J. 2008 May;27(3):386-91.
Tensile bond strength of one-step self-etch adhesives to Er:YAG laser-irradiated and non-irradiated enamel.
Kameyama A, Kato J, Aizawa K, Suemori T, Nakazawa Y, Ogata T, Hirai Y.
Department of Operative Dentistry, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba 261-8502, Japan. kameyama@tdc.ac.jp
This study determined the bond strengths to Er:YAG laser-irradiated and non-irradiated bovine enamel of three one-step self-etch adhesives (AQ Bond Plus (AQP), G-Bond (GB), and Clearfil Tri-S Bond (TS)) and one two-step self-etch adhesive (Clearfil Megabond (MB)). Eighty SiC paper-ground bovine enamel surfaces were used, of which half were laser-irradiated. The enamel surfaces were bonded to a resin composite with each adhesive, and tensile bond strengths were determined after 24 hours. For non-irradiated enamel groups, MB achieved greater bond strength to enamel than GB and TS (p < 0.05), but no significant difference was found between MB and AQP (p > 0.05). For laser-irradiated enamel groups, no significant differences were found among the four adhesives (p > 0.05). Additionally, for each adhesive, no significant differences were found between laser-irradiated and non-irradiated enamel. It was thus concluded that Er: YAG laser irradiation of enamel did not affect the tensile bond strength of one-step and two-step self-etch adhesives.
Oper Dent. 2008 Jul-Aug;33(4):456-60.
Comparison of enamel and dentin microshear bond strengths of a two-step self-etching priming system with five all-in-one systems.
Burrow MF, Kitasako Y, Thomas CD, Tagami J.
School of Dental Science, The University of Melbourne, Victoria, Australia. mfburrow@unimelb.edu.au
Data on the adhesive strength of new all-in-one adhesives are still relatively limited. This study compared the microshear bond strengths of five recent all-in-one self-etching priming systems (G-Bond, One-Up Bond-F Plus, Clearfil S3 Bond, Adper Prompt L-Pop and Go!) with a widely used two-step self-etching priming system (Clearfil SE Bond). Human molars were sectioned and finished with 600-grit SiC paper. Both enamel and dentin were bonded using adhesives with a 0.7 mm bonding diameter. Bond strengths were tested using a microshear bond test method at a crosshead speed of 1 mm/minute. The mean bond strengths and standard deviations were calculated and analyzed using ANOVA and the Tukey’s HSD test. Results showed the two-step self-etching system had significantly higher bond strengths to dentin. However, for enamel bond strength, Clearfil SE Bond showed no statistical difference to G-Bond and Go!; however, all of the other materials were statistically lower. It is necessary to examine these new materials clinically to determine their efficacy.
J Adhes Dent. 2008 Jun;10(3):211-8.
How can droplet formation occur in endodontically treated teeth during bonding procedures?
Ferrari M, Coniglio I, Magni E, Cagidiaco MC, Gallina G, Prati C, Breschi L.
Department of Fixed Prosthodontics and Dental Materials, School of Dental Medicine, University of Siena, Italy. m.ferrari@mclink.it
PURPOSE: The aim of this in vivo study was to clarify how blistering formation occurs along intraradicular dentin bonded interfaces. MATERIALS AND METHODS: Patients were selected and post space was prepared in vivo in endodontically treated teeth. Post space was etched, dried with ethanol, and bonded with one of the following adhesive systems: All Bond 2, XP-Bond, Clearfil SE Bond, Xeno III. The four adhesives were considered as representative of each bonding system class. An additional group was prepared with phosphoric acid treatment + application of Pre-Bond unfilled resin of All Bond 2, without the use of the primer agent. Etching was avoided for self-etching materials. Replicas of the post space were taken (1) after post space preparation; (2) after etching, rinsing, and drying; (3) after ethanol drying, and (4) after adhesive application. Replicas were analyzed with SEM and blisters were counted by independent observers. Statistical analysis was performed with Kruskal-Wallis ANOVA and Dunn’s multiple comparison tests at p = 0.05. RESULTS: No blister formation occurred on replicas taken prior to adhesive application, while blister formation was evident in all replicas of bonded interfaces, irrespective of the adhesive system. No statistical difference in the number of droplets was found between All Bond 2, XP-Bond, and Clearfil SE Bond. Xeno III exhibited the highest number of blisters. Specimens bonded with Pre-Bond unfilled resin of All Bond 2 without primer application showed no blister formation. CONCLUSION: This study revealed that blister formation occurs only if the priming agent of the adhesive system was applied, thus supporting the hypothesis that blistering occurs due to adhesive phase separation or insufficient solvent evaporation.
J Adhes Dent. 2008 Jun;10(3):183-8.
Sealing effectiveness of etch-and-rinse vs self-etching adhesives after water aging: influence of acid etching and NaOCl dentin pretreatment.
Monticelli F, Toledano M, Silva AS, Osorio E, Osorio R.
Department of Dental Materials, School of Dentistry, University of Granada, Granada, Spain.
PURPOSE: To determine the marginal leakage of Class V restorations bonded with etch-and-rinse and self-etching adhesives applied after different dentin pretreatments over a maximum storage time of 24 months. MATERIALS AND METHODS: Standardized mixed Class V cavities (5 mm x 3 mm and 2 mm deep) were cut on the buccal and lingual surfaces of 180 human molars. Two self-etching adhesive systems, Adper Prompt L-Pop (3M ESPE) and Clearfil SE Bond (Kuraray), and one etch-and-rinse bonding agent (One Step, Bisco) were applied as follows: 1. according to manufacturers’ instructions; 2. after 37% H3PO4 etching for 15 s; 3. after 37% H3PO4 etching for 15 s and 5% NaOCl aq application for 2 min. Teeth were stored for 24 h, 6, 12, and 24 months in saline solution at 37 degrees C before being stained in 0.5% solution of basic fuchsine. Dye penetration was scored on a 0 to 3 ordinal scale and analyzed with the Kruskal-Wallis H test (p < 0.05), Mann-Whitney U-test (p < 0.01), and Wilcoxon paired test (p < 0.05). RESULTS: Significant differences exist after using the tested adhesives at dentin and enamel margins. Adhesive type and substrate pretreatment had a significant effect on the long-term sealing of Class V restorations, and aging increased leakage overtime. The extent of leakage at the enamel margins was lower than that at dentin margins. One Step recorded the best results after 24 months. CONCLUSION: Optimal adhesion of restorative materials to enamel and dentin is hampered by a reduction in marginal seal over time. Alternative dentinal treatments (etching or collagen removal) might increase bonding efficacy, depending on the adhesive system used.
J Adhes Dent. 2008 Jun;10(3):173-82.
Effect of dentinal surface preparation on bond strength of self-etching adhesives.
Yiu CK, Hiraishi N, King NM, Tay FR.
Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong SAR, China. ckyyiu@hkucc.hku.hk
PURPOSE: This study examined the effects of cutting dentin with different burs at various speeds on the microtensile bond strength (muTBS) of two self-etching adhesive systems. MATERIALS AND METHODS: Flat deep dentin surfaces from 50 extracted human third molars were divided into 5 groups (n = 10) according to bur type and speed of rotation: (I) high-speed diamond bur, (II) low-speed diamond bur, (III) high-speed tungsten carbide bur, (IV) low-speed tungsten carbide bur. Controls were abraded with 600-grit SiC paper. A two-step self-etching adhesive, Clearfil SE Bond (SE, Kuraray) and a one-step self-etching adhesive, Clearfil S3 Bond (S3, Kuraray) were applied to dentin surfaces and light cured. Composite buildups were performed using Filtek Z250 (3M ESPE). For lTBS evaluation, composite-dentin beams of 0.8 mm2 were stressed to failure at a crosshead speed of 1 mm/min. The muTBS data were analyzed using two-way ANOVA and Tukey’s multiple comparison tests. Representative fractured beams from each group were prepared for fractographic analysis under SEM. RESULTS: Two-way ANOVA showed that the effects of dentin surface preparations, adhesive systems, and their interaction were statistically significant (p < 0.001). The muTBS was the highest when bonding SE to dentin surface prepared with 600-grit SiC abrasive paper (47.3 +/- 7.4 MPa), followed by high-speed tungsten carbide burs (40.8 +/- 6.1 MPa), and the lowest when bonding S3 to dentin surfaces prepared with a high-speed diamond bur (15.2 +/- 6.2 MPa). SEM observation of the fractured surfaces revealed mixed and adhesive failures for SE groups, while in the S3 groups, adhesive failures predominated with numerous inclusion droplets. CONCLUSION: Higher bond strengths are achieved with SE bond when applied on dentin surfaces prepared with tungsten carbide burs. Proper bur and adhesive selection are essential to optimize dentin adhesion of self-etching adhesives.
Dent Mater. 2008 Jun 23.
The viscoelastic behavior of dental adhesives: A nanoindentation study.
Sadr A, Shimada Y, Lu H, Tagami J.
Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan.
OBJECTIVES: In order to predict the long-term performance of dental adhesives, it is necessary to understand their mechanical properties. The objective of this study was to use a new nanoindentation technique to characterize the in-plane linear viscoelastic properties of dental adhesive layers. METHODS: The dental adhesives used were Clearfil SE Bond (CSE) and Clearfil Tri-S Bond (CTS) by Kuraray Medical and Single Bond (SIB) and Single Bond Plus (SBP) by 3M ESPE. A thin film of each adhesive was made on a micro-glass slide, and was then tested on a nanoindenter system (ENT 1100, Elionix) with a Berkovich indenter at a constant loading rate of 0.1mN/s up to a maximum load of 1.8mN. The load-displacement data of the loading segment were fitted to a curve to find best fit parameters for a generalized Kelvin viscoelastic model, from which creep compliance and Young’s modulus were calculated. The modulus results were compared to the values calculated by the nanoindentation device. RESULTS: The experimental data fitted well to the viscoelastic model for all materials (R>0.9999). SIB and CTS showed higher creep compliance compared to SBP and CSE. The modulus values obtained using the model were 4.0, 2.6, 2.4 and 4.2GPa for CSE, CTS, SIB and SBP, respectively. The nanoindentation default software designed for time-independent materials significantly overestimated the modulus values up to 2.5 times. CONCLUSION: As generally expected for polymer materials, the adhesives tested showed time-dependent viscoelastic behavior. The mechanical evaluation techniques developed for time-independent materials ignore this behavior and may not be appropriate for dental adhesives.
Dent Mater. 2008 Jun 19. [Epub ahead of print]
Effect of adhesive hydrophilicity and curing time on the permeability of resins bonded to water vs. ethanol-saturated acid-etched dentin.
Cadenaro M, Breschi L, Rueggeberg FA, Agee K, Di Lenarda R, Carrilho M, Tay FR, Pashley DH.
Department of Biomedicine, Unit of Dental Sciences and Biomaterials, University of Trieste, Italy.
OBJECTIVE: This study examined the ability of five comonomer blends (R1-R5) of methacrylate-based experimental dental adhesives solvated with 10 mass% ethanol, at reducing the permeability of acid-etched dentin. The resins were light-cured for 20, 40 or 60s. The acid-etched dentin was saturated with water or 100% ethanol. METHOD: Human unerupted third molars were converted into crown segments by removing the occlusal enamel and roots. The resulting crown segments were attached to plastic plates connected to a fluid-filled system for quantifying fluid flow across smear layer-covered dentin, acid-etched dentin and resin-bonded dentin. The degree of conversion of the resins was measured using Fourier transform infrared spectroscopy. RESULT: Application of the most hydrophobic comonomer blend (R1) to water-saturated dentin produced the smallest reductions in dentin permeability (31.9, 44.1 and 61.1% after light-curing for 20, 40 or 60s, respectively). Application of the same blend to ethanol-saturated dentin reduced permeability of 74.1, 78.4 and 81.2%, respectively (p<0.05). Although more hydrophilic resins produced larger reductions in permeability, the same trend of significantly greater reductions in ethanol-saturated dentin over that of water-saturated dentin remained. This result can be explained by the higher solubility of resins in ethanol vs. water. SIGNIFICANCE: The largest reductions in permeability produced by resins were equivalent but not superior, to those produced by smear layers. Resin sealing of dentin remains a technique-sensitive step in bonding etch-and-rinse adhesives to dentin.
Acta Odontol Scand. 2008 Jun;66(3):159-68.
Bonding of one-step and two-step self-etching primer adhesives to dentin with different tubule orientations.
Asande Adebayo O, Francis Burrow M, John Tyas M.
School of Dental Science, The University of Melbourne, Victoria, Australia.
OBJECTIVES: To determine the microshear bond strengths of five ‘all-in-one’ adhesives and two 2-step self-etching primer adhesives to dentin with different tubule orientations and to compare bond strengths between the adhesives. MATERIAL AND METHODS: Human adult molar teeth were sectioned to obtain dentin pieces with tubule orientations perpendicular or parallel/oblique to the bonded surface. Two 2-step self-etching primer adhesives (Clearfil SE Bond (CSE), Optibond Solo Plus SE Bond (Op. SE)) and five all-in-one adhesives (Clearfil S(3) Bond (S(3)), Optibond All-in-One Bond (Op. AIO), G-Bond, Go!, and Xeno IV) were applied to dentin in accordance with the manufacturers’ instructions. Resin composite cylinders were bonded to superficial and deep dentin using microtubes (0.75 mm internal diameter and 1.5 mm high). Bonded specimens were stored in water at 37 degrees C for 24 h, then stressed in shear at a cross-head speed of 1 mm/min until bond failure. Maximum load at failure (N) was recorded and converted to MPa. Statistical analyses were carried out using independent samples t-test and one-way ANOVA with Tukey’s HSD test. RESULTS: Though bond strengths varied slightly, four all-in-one adhesives (Op. AIO, G-Bond, Go!, and Xeno IV) showed no significant differences in microshear bond strengths regardless of dentin depth (superficial or deep) or dentin tubule orientation (perpendicular or parallel/oblique). CSE, Op. SE, and S(3) showed significantly lower bond strengths to deep dentin with a tubule orientation perpendicular to the surface. CONCLUSION: Most of the all-in-one adhesive systems used in this study appear to bond equally well to dentin independently of tubule orientation and depth. One two-step self-etching primer adhesive bonded significantly better than the all-in-one adhesives.
J Dent. 2008 Jun 10.
Comparison of the hybrid layer formed by Silorane adhesive, one-step self-etch and etch and rinse systems using confocal micro-Raman spectroscopy and SEM.
Santini A, Miletic V.
The University of Edinburgh, Postgraduate Dental Institute, Lauriston Building (4th floor), Lauriston Place, Edinburgh EH3 9HA, United Kingdom.
OBJECTIVES: To determine the extent of the hybrid layer (HL) of the novel adhesive system (Silorane, 3M ESPE) compared to one-step and etch and rinse adhesive systems, using 2D confocal micro-Raman spectroscopy and SEM. METHODS: Silorane adhesive system was compared to two one-step self-etch (G Bond, GC; AdheSE One, Ivoclar Vivadent) and etch and rinse (Excite, Ivoclar Vivadent) as controls. Adhesives were applied to human dentine, cured and sections prepared perpendicular to the flat adhesive-dentine surface. Two-dimensional micro-Raman mapping was performed over 20mumx20mum areas across the adhesive-dentine interface. SEM micrographs of the same specimens were obtained. One-way ANOVA (Tukey’s post-test) was used to analyse the differences in HL thickness among the four adhesive systems and the paired t-test to compare the results obtained by micro-Raman and SEM for each adhesive. RESULTS: Silorane adhesive system formed a HL of comparable thickness to methacrylate-based but thicker than the acrylamide-based one-step self-etch adhesives from SEM analysis. A gradual decrease in adhesive penetration was observed in all systems. A 1-mum zone, between the cured primer and bond was identified by Raman but not visualised on SEM. Compared to SEM, HL calculated from Raman data were always greater. CONCLUSIONS: Micro-Raman spectroscopy gives a more precise indication of dentine demineralisation and monomer infiltration and highlights the intermediate zone of approximately 1mum between Silorane primer and bond, not visible with SEM at x10,000 magnification. Giving as it does, a compilation of many linear scans it allows HL mean values to be calculated.
Clin Oral Investig. 2008 Mar;12(1):1-8. Epub 2007 Nov 27.
In vitro and in vivo studies on the toxicity of dental resin components: a review.
Goldberg M.
Faculté de Chirurgie Dentaire, University Paris 5, EA 2496, 1, rue Maurice Arnoux, 92120, Montrouge, France. mgoldod@aol.com
In vitro and in vivo studies have clearly identified that some components of restorative composite resins, adhesives, and resin-modified glass ionomer cements are toxic. The mechanisms of cytotoxicity are related firstly to the short-term release of free monomers occurring during the monomer-polymer conversion. Secondly, long-term release of leachable substances is generated by erosion and degradation over time. In addition, ion release and proliferation of bacteria located at the interface between the restorative material and dental tissues are also implicated in the tissue response. Molecular mechanisms involve glutathione depletion and reactive oxygen species (ROS) production as key factors leading to pulp or gingival cell apoptosis. Experimental animal approaches substantiate the occurrence of allergic reactions. There is a large gap between the results published by research laboratories and clinical reports.
J Adhes Dent. 2008 Feb;10(2):135-44.
Sodium hypochlorite as dentin pretreatment for etch-and-rinse single-bottle and two-step self-etching adhesives: atomic force microscope and tensile bond strength evaluation.
Fawzy AS, Amer MA, El-Askary FS.
Dental Biomaterials Department, Faculty of Dentistry, Ain-Shams University, Cairo, Egypt.
PURPOSE: The aim of this study was to evaluate the effect of using 5.25% commercial sodium hypochlorite treatment prior to the application of etch-and-rinse and self-etching adhesives on dentin surface microtopography and tensile bond strength. MATERIALS AND METHODS: Thirty-two noncarious, nonrestored human third molars were collected. The occlusal enamel of all teeth was removed using diamond disks to expose flat dentin surfaces. The exposed dentin surfaces were abraded using 600-grit SiC disks, to create a uniform dentin smear layer. For AFM characterization, 12 teeth were equally divided into 4 groups according to the proposed dentin surface treatment. Three dentin disks, 2 mm thick, were evaluated per group using tapping mode assessment. Twenty teeth were used for TBS and SEM evaluation and were equally divided into 4 groups, according to the proposed dentin surface treatment. For TBS, 8 dentin/composite slabs, 2 mm thick, were used in each group, while for SEM evaluation 2 slabs were used. Each slab was tested in tension at a crosshead speed of 0.5 mm/min until failure occurred. The samples were examined using SEM operated at 30 kv to evaluate the hybrid layer photographically at 1500X. Statistical analysis was carried out using StatsDirect 2.5.7. One-way ANOVA followed by Tukey-Kramer multiple-comparison post-hoc tests were performed to test the difference between roughness parameters and TBS between groups. RESULTS: Sodium hypochlorite followed by the application of 37% phosphoric acid significantly increased the arithmetic average of the absolute values of surface height deviations (Sa), the surface area ratio which expresses the ratio between the surface area (taking the z height into account) and the area of the flat x,y plane (Sdr), and the surface bearing index (Sbi) parameters, while the application of sodium hypochlorite prior to the application of the self-etching primer significantly increased the valley fluid retention index (Svi) parameter. Self-etching primer without sodium hypochlorite pretreatment significantly increased the core fluid retention index (Sci) parameter. Sodium hypochlorite/AdheSE (7.42 +/- 2.16 MPa) significantly increased TBS value compared to other groups. However, no statistically significant difference was found between sodium hypochlorite/Excite (4.68 +/- 1.26 MPa), AdheSE (4.42 +/- 1.36), and Excite (4.06 +/- 1.35). Remnants of smear layer were detected with areas devoid of resin tags in SEM images of samples bonded with AdheSE self-etching adhesive, in contrast to samples bonded with sodium hypochlorite followed by AdheSE self-etching adhesive. CONCLUSION: The application of 5.25% commercial sodium hypochlorite with rubbing action for 60 s (total application time 120 s) seems to positively influence the TBS of the self-etching adhesive; however, it has no significant effect on TBS of etch-and-rinse single-bottle adhesive to dentin. The addition of functional roughness parameters to study the dentin surface was shown to be of importance in evaluating the relationship between bond strength and surface topography of conditioned dentin.
J Adhes Dent. 2008 Feb;10(2):127-33.
Effect of adhesive system type and tooth region on the bond strength to dentin.
Marques de Melo R, Galhano G, Barbosa SH, Valandro LF, Pavanelli CA, Bottino MA.
São Jose dos Campos Dental School, São Paulo State University, São José dos Campos, SP, Brazil. marquesdemelo@gmail.com
PURPOSE: This study evaluated the bond strength of two etch-and-rinse adhesive systems (two- and three-step) and a self-etching system to coronal and root canal dentin. MATERIALS AND METHODS: The root canals of 30 human incisors and canines were instrumented and prepared with burs. The posts used for luting were duplicated with dual resin cement (Duo-link) inside Aestheti Plus #2 molds. Thus, three groups were formed (n = 10) according to the adhesive system employed: All-Bond 2 (TE3) + resin cement post (rcp) + Duo-link (Dl); One-Step Plus (TE2) + rcp + Dl; Tyrian/One-Step Plus (SE) + rcp + Dl. Afterwards, 8 transverse sections (1.5 mm) were cut from 4 mm above the CEJ up to 4 mm short of the root canal apex, comprising coronal and root canal dentin. The sections were submitted to push-out testing in a universal testing machine EMIC (1 mm/min). Bond strength data were analyzed with two-way repeated measures ANOVA and Tukey’s test (p < 0.05). RESULTS: The relationship between the adhesives was not the same in the different regions (p < 0.05). Comparison of the means achieved with the adhesives in each region (Tukey; p < 0.05) revealed that TE3 (mean +/- standard deviation: 5.22 +/- 1.70) was higher than TE2 (2.60 +/- 1.74) and SE (1.68 +/- 1.85). CONCLUSION: Under the experimental conditions, better bonding to dentin was achieved using the three-step etch-and-rinse system, especially in the coronal region. Therefore, the traditional etch-and-rinse three-step adhesive system seems to be the best choice for teeth needing adhesive endodontic restorations.
J Adhes Dent. 2008 Feb;10(2):119-26.
Effects of de- and remineralization of dentin on bond strengths yielded by one-, three-, and four-step adhesives.
Schmidlin PR, Siebenmann J, Kocher P, Seemann R, Attin T, Bindl A.
Clinic for Preventive Dentistry, Periodontology and Cariology, Center for Dental and Oral Medicine, University of Zürich, Switzerland. patrick.schmidlin@zzmk.unizh.ch
PURPOSE: To assess the effect of different peri- and intertubular dentin mineralization conditions and etching on shear bond strength in vitro. MATERIALS AND METHODS: One hundred fifty crowns of extracted bovine incisors were embedded in resin and ground to expose the buccal coronal dentin. Sixty specimens were subjected to a demineralizing solution (DS) and another 60 teeth to a bacterial-based laboratory caries model (S. mutans, SM). Thirty specimens of each demineralization protocol (DS and SM) were randomly selected and remineralized (-R). Thirty sound dentin specimens served as control (C). Resin composite buildups (Tetric) were bonded after application of one of the following adhesives: a one-step self-etching adhesive (Xeno III), and a self-etching adhesive (Syntac Classic) without (three-step) and with prior additional 35% phosphoric acid etching (etch-and-rinse, four-step). Teeth were subjected to shear bond strength testing in a universal testing device at a crosshead speed of 0.5 mm/min (Ultradent method). RESULTS: Bond strength value for group C ranged from 6.3 to 8.4 MPa (p > 0.05). DS and DS-R samples showed in creased bond strength with the one-step adhesive (11.6 MPa, p < 0.05), whereas the three-step adhesive with additional etching showed decreased bond strength (3.2 MPa, p < 0.05). SM samples showed the lowest bond strength of all adhesive systems (range 1.1 to 1.5 MPa, p > 0.05). Remineralization showed no effect on the latter group. CONCLUSION: The degree of mineralization of the dentin is important for adhesion. Additional etching with phosphori acid reduced bond strength of a three-step adhesive.
Braz Oral Res. 2008 Jan-Mar;22(1):43-7.
In vivo qualitative analysis of the biocompatibility of different cyanoacrylate-based adhesives.
Moretti Neto RT, Mello I, Moretti AB, Robazza CR, Pereira AA.
Department of Clinics and Surgery, School of Dentistry, Federal University of AlfenasPasso Fundo, RS, Brazil.
Cyanocrylates have been widely used in the medical and dental fields for several years. In Dentistry, cyanoacrylates have been used for suturing, pulp capping, as retrofilling material in endodontic surgeries, and as cervical plug for pulpless teeth bleaching. The biocompatibility of these adhesives has been the topic of many researches and subcutaneous implantation is an effective methodology for these studies. The present study evaluated the biocompatibility of three different cyanoacrylate-based adhesives. Thirty-six Wistar rats were used, divided into four groups of 9 animals each: A (control) – distilled water, B – cyanoacrylate ester (Super Bonder), C – n-butyl-cyanoacrylate (Histoacryl) and D – alpha-cyanoacrylate (Three Bond). The materials were dispensed in sponges of polyvinyl chloride, the animals were incised and the sponges were inserted in the subcutaneous tissue and sutured. Each group was sub-divided according to the time of sacrifice of the animals: 7, 21 and 45 days. Subjective analysis of the histologic material showed that all groups presented some degree of irritability, but the inflammatory reaction decreased with the experimental time in all groups. Group D showed an inflammatory reaction which was closer to that of the control group and was considered to have good biocompatibility. Groups B and C were similar and presented more aggressive inflammatory reactions when compared to the control group. Based on the results, it was concluded that alpha-cyanoacrylate (Three Bond) was the most biocompatible adhesive because it caused the lowest levels of inflammation.
J Adhes Dent. 2008 Feb;10(1):35-9.
Effect of evaporation of solvents from one-step, self-etching adhesives.
Furuse AY, Peutzfeldt A, Asmussen E.
Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil. ayfuruse@hotmail.com
PURPOSE: To investigate whether and to what extent the bonding capacity of one-step, self-etching adhesives is influenced by the degree to which solvent is evaporated. MATERIALS AND METHODS: Seven one-step, self-etching adhesives were tested (Adper Prompt L-Pop, Clearfil S3 Bond, Futurabond NR, G-Bond, Hybrid Bond, iBond, Xeno III). The variation in degree of evaporation was obtained by varying the duration of the air-blowing step. The duration required to immobilize the adhesive layer, as established in a pilot study, was used as control. Two experimental air-blowing durations, shorter (half the control duration) and longer (double the control duration) than the control duration, were chosen. The resin composite Herculite XRV was bonded to flat human dentin surfaces treated with one of the adhesives following manufacturer’s instructions, except for the air-blowing duration after application. After being stored in water at 37 degrees C for 1 week, the bonded specimens were broken in shear. Failure modes were evaluated under stereomicroscope. RESULTS: Air-blowing duration and brand of adhesive both had an effect on shear bond strength. An interaction was found between adhesive and air-blowing duration. Some adhesives were insensitive to variations in air-drying duration, but in general, air-blowing durations shorter than the control duration produced lower shear bond strengths. Significant effects of adhesive and air-blowing duration were also detected in relation to failure mode. More adhesive failures were observed with shorter air-blowing durations. A significant negative correlation between number of adhesive failures and bond strength was found. CONCLUSION: On the basis of this in vitro study, it may be concluded that the one-step, self-etching adhesives evaluated were sensitive to degree of evaporation of the solvents.
J Adhes Dent. 2008 Feb;10(1):25-33.
Influence of Er,Cr:YSGG laser treatment on the microtensile bond strength of adhesives to dentin.
Cardoso MV, Coutinho E, Ermis RB, Poitevin A, Van Landuyt K, De Munck J, Carvalho RC, Lambrechts P, Van Meerbeek B.
Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Belgium.
PURPOSE: In light of the concept of minimally invasive dentistry, erbium lasers have been considered as an alternative technique to the use of diamond burs for cavity preparation. The purpose of this study was to assess the bonding effectiveness of adhesives to Er,Cr:YSGG laser-irradiated dentin using irradiation settings specific for cavity preparation. MATERIALS AND METHODS: Fifty-four midcoronal dentin surfaces, obtained from sound human molars, were irradiated with an Er,Cr:YSGG laser or prepared with a diamond bur using a high-speed turbine. One etch-and-rinse (Optibond FL/Kerr) and three self-etching adhesives (Adper Prompt L-Pop/3M ESPE, Clearfil SE Bond/Kuraray, and Clearfil S3 Bond/Kuraray) were used to bond the composite to dentin. The microtensile bond strength (microTBS) was determined after 24 h of storage in water at 37 degrees C. The Kruskal-Wallis test was used to determine pairwise statistical differences (p < 0.05). Prepared dentin surfaces, adhesive interfaces, and failure patterns were analyzed using a stereomicroscope and Field-emission gun Scanning Electron Microscopy (Feg-SEM). RESULTS: Significantly lower microTBS was observed to laser-irradiated than to bur-cut dentin (p < 0.05), irrespective of the adhesive employed. Feg-SEM photomicrographs of lased dentin revealed an imbricate patterned substrate and the presence of microcracks at the dentin surface. CONCLUSION: Morphological alterations produced by Er,Cr:YSGG laser-irradiation adversely influence the bonding effectiveness of adhesives to dentin.
J Adhes Dent. 2008 Feb;10(1):7-16.
Critical analysis of the influence of different parameters on the microtensile bond strength of adhesives to dentin.
Poitevin A, De Munck J, Van Landuyt K, Coutinho E, Peumans M, Lambrechts P, Van Meerbeek B.
Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Catholic University of Leuven, Leuven, Belgium.
PURPOSE: To evaluate how six different test parameters (TP) of the microtensile bond strength (microTBS) methodology influence the test outcome. MATERIALS AND METHODS: The microtensile bond strength of adhesives bonded to dentin was measured, and the resultant failure patterns and stress-time graphs were analyzed, varying the microTBS specimen-fixation mode (TP1), the microspecimen geometry (TP2), the microspecimen bond surface area (TP3), the remaining dentin thickness of the microspecimens (TP4), the procedure employed to glue the microspecimen to the microTBS jig (TP5), and the microTBS crosshead speed (TP6). RESULTS: The orientation of the microspecimens to the actual interface primarily influenced the resultant microTBS value and the eventual failure pattern. A notched jig consistently yielded significantly higher mciroTBS values than samples fixed onto a flat jig or following a “top-bottom” design (TP1). A higher bond strength, a lower standard deviation/coefficient of variation, a failure closer to the interface, and a more representative number of specimens per tooth were obtained for nontrimmed, square microspecimens (TP2). The most reproducible results were obtained using square specimens of 1 mm2 (TP3), which could also be most easily prepared. The remaining dentin thickness (TP4) was an influential factor as well, whereas the microspecimen gluing protocol (TP5) and the crosshead speed (TP6) appeared less influential. CONCLUSION: As several test parameters significantly influenced the microTBS outcome, sufficient attention should be paid to these methodology variables with regard to the microTBS-test reliability and reproducibility.
Oper Dent. 2008 Jan-Feb;33(1):89-95.
Microtensile dentin and enamel bond strengths of recent self-etching resins.
Brackett WW, Tay FR, Looney SW, Ito S, Haisch LD, Pashley DH.
Department of Oral Rehabilitation, School of Dentistry, Medical College of Georgia, Augusta, GA, USA. wbrackett@mail.mcg.edu
In this study, the microtensile bond strengths of resin composites to dentin and enamel produced by recently introduced self-etching resins were determined. Included were two adhesives with self-etching primers, Clearfil SE (Kuraray) and Peak SE (Ultradent), four self-etching adhesives, Optibond All-In-One (Kerr), Clearfil S3 (Kuraray), Adper Prompt L-Pop (3M ESPE) and iBond (Heraeus Kulzer) and, as a positive control, PQ1 (Ultradent), an etch-and-rinse adhesive. Each product was evaluated using the same hybrid resin composite, Z250 (3M ESPE). Testing was performed after 48 hours using a “non-trimming” microtensile test at a crosshead speed of 0.6 mm/minute. Sample size was five teeth per group, with the value for each tooth calculated by averaging the bond strengths of seven beams derived from it. Mean values in MPa (SD) for dentin were: Clearfil SE 81.6 (3.5),a Peak SE 80.3 (9.9),a PQ1 73.4 (4.9),a,b Optibond All-In-One 64.4 (5.9),b Clearfil S3 62.5 (2.2),b,c iBond 51.0 (4.0)c and Prompt L-Pop 33.9 (6.4).d Mean values in MPa (SD) for enamel were: PQ1 55.6 (2.5),a Clearfil SE 54.1 (5.4),a Prompt L-Pop 54.0 (5.4),a Peak SE 51.8 (1.5),a,b Clearfil S3 44.3 (5.2),b,c Optibond All-In-One 40.1 (2.1)c,d and iBond 33.8 (3.3).d (Values for each substrate with the same letter were not significantly different, one-way ANOVA, Tukey-Kramer Multiple Comparison Test, p<0.05.) Compared to the positive control, PQ1, only adhesives with self-etching primers, Clearfil SE and Peak SE, were as effective in bonding to both enamel and dentin. With the exception of Prompt L-Pop, scanning electron micrographs of the etched enamel surface produced by self-etching products indicated far less surface topography than conventional etching, even for self-etching primer systems producing the same bond strengths as the etch-and-rinse adhesive.
Clin Oral Investig. 2008 Mar 28 [Epub ahead of print]
Two-year clinical performance of two one-step self-etching adhesives in the restoration of cervical lesions.
Schattenberg A, Werling U, Willershausen B, Ernst CP.
Clinic for Restorative Dentistry, Johannes Gutenberg-University of Mainz, Augustusplatz 2, 55131, Mainz, Germany, schattan@uni-mainz.de.
The aim of the study was to evaluate the clinical performance of two different one-step self-etching adhesives (Hybrid Bond/Sun Medical, Xeno III/Dentsply) in adhesive cervical resin composite restorations. In accordance with a split-mouth study design, 50 patients (57.3 +/- 13.5) received at least one pair of restorations. In each of two comparable cervical cavities, either the adhesive systems Hybrid Bond or Xeno III was used with the resin composite Filtek Supreme (3M ESPE). After 6, 12 and 24 months, the restorations were scored according to the Ryge and California Dental Association criteria. After 2 years, the resulting scores (percent) of the Ryge evaluation for the groups Hybrid Bond/ Filtek Supreme and Xeno III/ Filtek Supreme were marginal integrity, Alpha (92/78), Bravo (8/2), Charlie (0/0) and Delta (0/10); anatomic form, Alpha (92/82), Bravo (8/8) and Charlie (0/10); secondary caries, Alpha (100/100) and Bravo (0/0); marginal discoloration, Alpha (80/84), Bravo (20/12), Charlie (0/0) and not available (0/4); color match, Oscar (39/47), Alpha (51/45), Bravo (10/4), Charlie (0/0) and not available (0/4); surface, Romeo (78/69), Sierra (22/22), Tango (0/0) and Victor (0/10); tooth vitality, Alpha (98/94), Bravo (2/6); and integrity of tooth, alpha 1 (96/96) and alpha 2 (4/4). After 2 years, all Hybrid Bond restorations were retained and showed clinically acceptable results, while five Xeno III restorations were lost in part or in toto. For marginal integrity, anatomic form and surface, significant differences (p < 0.05) were found but did not prove statistically significant after Bonferroni adjustment
Effect of the self-etching adhesives system on human pulp fibroblast
Zhang M, Feng Y, Huang XJ, Lei LS, Zheng BQ, Lu YG.
Department of Endodontics, The Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou 350002, China.
OBJECTIVE: To compare and evaluate the biocompatibility of three kinds of dentin bonding agents Xeno III (XO), Adper Prompt (AP), Single bond2 (SB) through cell culture in vitro. METHODS: Three kinds of dentin bonding agents (XO, AP, SB) were applied on the surface of the dental slices which were 5.0 mm in diameter and 0.5 mm in depth. By immersing the slices into the DMEM culture medium, the maceration extracts were obtained. Normal dental pulps of teenagers were collected and human pulp fibroblast was cultured using tissue explant method. The fifth generation pulp cells were exposed to culture medium containing different concentrations of maceration extracts (100.0%, 50.0%, 25.0%, 12.5%) for 24, 72, 120 h. At last, MTT method was used to evaluate the cytotoxicity of the dentin bonding agents on human pulp fibroblast. RESULTS: The results showed that all three kinds of dentin bonding systems had cytotoxicity to human pulp fibroblast in different degree in vitro. The cytotoxicity of XO and AP was less than SB. The difference was statistically significant (P<0.05). CONCLUSION: The results of cell culture in vitro indicated that total-etching adhesives system has more irritation to pulp than self-etching adhesives system.
Hua Xi Kou Qiang Yi Xue Za Zhi. 2008 Feb;26(1):77-81.
Two-dimensional morphology of microleakage between dentin and adhesives
Zhao XY, He HM, Liu F, Wang JC.
Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China.
OBJECTIVE: To observe the two-dimensional morphology of microleakage between dentin and adhesives. METHODS: The occlusal enamel of human third molar was cut out and the dentin exposed, followed by the application of dental adhesive (Prime & Bond NT, Contax and Adper Prompt), then a composite resin crown was built up. After storage in water (37 degrees C) for 24 h, all teeth were vertically serially sectioned into matchstick-shaped specimens through the bond interfaces. Half of the specimens from one tooth were subjected to thermal cycling and another half was stored in water (37 degrees C). All specimens were then immersed in ammoniacal silver nitrate solution, followed by developing solution. At last all specimens were subjected to microtensile test at a cross-head speed of 1.0 mm/min and their fractured surfaces were observed under scanning electron microscope. RESULTS: The planar contour of all the silver leakage was various branching, treelike shape, spreading from the border of section to the center. CONCLUSION: The planar contour of microleakage is treelike shape and its extent is influenced by adhesives and thermal cycling.
Eur J Oral Sci. 2008 Apr;116(2):184-93.
Micropermeability of current self-etching and etch-and-rinse adhesives bonded to deep dentine: a comparison study using a double-staining/confocal microscopy technique.
Sauro S, Pashley DH, Mannocci F, Tay FR, Pilecki P, Sherriff M, Watson TF.
Dental Biomaterials Science, Biomimetics and Biophotonics, King’s College London Dental Institute at Guy’s, St Thomas Hospitals, London, UK. salvatore.sauro@kcl.ac.uk
Water sorption decreases the mechanical properties and the bond strengths of resin-bonded dentine. The aim of this study was to evaluate the micropermeability of several self-etching and etch-and-rinse adhesives. Optibond FL, Silorane, Scotchbond 1XT, G-Bond, and DC-Bond were bonded under simulated pulpal pressure. A 10 wt% solution of ammoniacal silver nitrate and a 1 wt% solution of rhodamine B were injected into the pulp chamber at 20 cm of water pressure. The dentine-adhesive interfaces were examined using a confocal scanning microscope. Micropermeability was detected in all the adhesives. DC-Bond, G-Bond, and Scotchbond 1XT showed voids along the resin-bonded interface. Silorane and Optibond FL showed an adhesive layer that was free from water trees and micropermeability. The double staining technique is a method that gives accurate results in the study of the resin-dentine micropermeability. Each class of adhesive has a different distribution of micropermeability. The higher the micropermeability, the higher the risk of defects at the resin-dentine interface, which may represent the pathway for hydrolytic and enzymatic degradation of resin-dentine bonds over time.
Eur J Oral Sci. 2008 Apr;116(2):177-83.
Quantitative micro-Raman assessment of dentine demineralization, adhesive penetration, and degree of conversion of three dentine bonding systems.
Santini A, Miletic V.
Postgraduate Dental Institute, University of Edinburgh, Edinburgh, UK. ariosantini@hotmail.com
Unreacted monomers in adhesive systems may cause a reduction in material properties, an increase in the long-term instability of the restoration, and pulpal irritation. The degree of dentine demineralization, adhesive penetration, and the degree of conversion (DC) across the dentine-adhesive interface of self-etch adhesives were measured using micro-Raman spectroscopy. Two-step, self-etch AdheSE, one-step self-etch AdheSE One, and etch-and-rinse Excite (control) (Ivoclar Vivadent AG, Schaan, Liechtenstein) were studied. Nine human molars were allocated to three groups and a flat dentine surface was prepared. A smear layer was produced by grinding dentine with 600-grit silicone-carbide discs under water. After application and polymerization of the adhesive, teeth were sectioned to produce four 1-mm-thick slices per tooth for micro-Raman spectroscopy. There were statistically significant differences in the depth of dentine demineralization between all adhesives. The depth and degree of demineralization decreased in the order: Excite>AdheSE>AdheSE One. The mean +/- standard deviation (SD) values for DC within the adhesive layer were 85.2 +/- 2.9% (Excite), 81.4 +/- 4.2% (AdheSE), and 54.3 +/- 10.1% (AdheSE One), and within the hybrid layer were 55.2 +/- 22.5% (Excite), 65.1 +/- 16.9% (AdheSE), and 42.0 +/- 16.2% (AdheSE One). All systems showed a discrepancy between dentine demineralization and adhesive penetration. A significant amount of unreacted monomers were associated with all systems but particularly with the etch-and-rinse system.
Dent Mater. 2008 Feb 21 [Epub ahead of print]
Wettability and bonding of self-etching dental adhesives Influence of the smear layer.
Aguilar-Mendoza JA, Rosales-Leal JI, Rodríguez-Valverde MA, González-López S, Cabrerizo-Vílchez MA.
Biocolloid and Fluid Physics Group, Department of Applied Physics, University of Granada, Spain.
OBJECTIVES: To evaluate dentin wettability and bonding of self-etching and total-etch adhesives on smear layer-covered and smear layer-free dentin. METHODS: Three self-etching adhesives (Clearfil SE Bond, AdheSE and Xeno III) and one total-etch adhesive (SingleBond) were evaluated. The substrates were mid coronal smear layer-covered and smear layer-free dentin. Dentin wettability by resins was studied from contact angle measurement using sessile drop method and Axisymmetric Drop Shape Analysis (ADSA). Shear-bond strength was evaluated using a push-out technique (ad hoc design). Data were analysed with two-way ANOVA and Tukey’s test. RESULTS: Similar values of dentin wettability were obtained for all adhesives tested regardless the presence of smear layer. Even though, Xeno III and AdheSE exhibited slightly lower wettability (higher contact angles values) on smear layer-free dentin. Likewise, the presence of smear layer did not affect the shear-bond strength. Total-etch adhesive obtained higher shear-bond strength than self-etching adhesives, which obtained similar values. SIGNIFICANCE: Wettability is similar between self-etching and total-etch adhesives. The smear layer affects slightly the wettability of self-etching adhesives. Shear-bond strength is not sensitive to the smear layer presence. Total-etch adhesion is stronger than self-etching adhesion. There is no clear relationship between wettability and bond strength.
Dent Mater J. 2007 Nov;26(6):773-84.
Comparison of bonding ability of single-step self-etching adhesives with different etching aggressiveness to root dentin.
Kaneshiro AV, Imazato S, Ebisu S.
Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
The aim of this study was to compare the bonding ability of single-step self-etching adhesives with different degrees of etching aggressiveness to root dentin. Composite restorations were placed on sound or caries-affected root dentin using a “strong” (Adper Prompt L-Pop, Absolute) or “mild” (Clearfil Tri-S Bond, Reactmer Bond) system. Immediately after restoration placement and after 24-hour storage in distilled water, the bonding interface was examined by scanning electron microscopy. Microtensile bond strength (MTBS) on sound root dentin was also measured with each storage condition. The adhesives with strong etching aggressiveness demonstrated interfacial integrity immediately after restoration and also after 24 hours of storage. Conversely, the “mild” adhesives showed debonding immediately after restoration. There were no statistical differences in MTBS among the four systems, nor between the two storage periods for each material. For restorations on root dentin using single-step adhesives, “strong” systems were thus recommended as they favorably produced a stable bond since the early stage.
Dent Mater J. 2007 Sep;26(5):677-86.
In vitro durability of one-bottle resin adhesives bonded to dentin.
Hashimoto M, Fujita S, Kaga M, Yawaka Y.
Department of Dentistry for Children and Disabled Persons, Hokkaido University, Graduate School of Dental Medicine, Sapporo, Japan. masanori-h@mue.biglobe.ne.jp
Recently, one-bottle resins adhesives have been developed to reduce the number of clinical steps of resin application. They are now widely used in clinical dental practice. However, little is known regarding the detailed mechanism of bond degradation. Therefore, this study evaluated the durability of one-bottle resin adhesives using long-term water storage testing. Resin-dentin bonded specimens were prepared using five commercially available one-bottle resin adhesives. The specimens were sectioned perpendicular to the adhesive interface to produce beams and stored in distilled water for 24 hours (control), 100, 200, and 300 days. After the water storage, each beam was subjected to a microtensile bond test and then SEM fractography was performed on the fractured surface. Compared to the bond strength at 24 hours after bonding (control), the bond strength of all tested adhesives were significantly decreased after 100 or more days in water. SEM fractography revealed a typical type of deterioration in the adhesive-composite interface that might cause a decline in bond strength after aging.
Oper Dent. 2007 Nov-Dec;32(6):602-9.
Effects of filling techniques on the regional bond strength to lateral walls in Class I cavities.
Félix SA, González-López S, Mauricio PD, Aguilar-Mendoza JA, Bolanos-Carmoña MV.
Department of Prosthodontics and Occlusion/Orofacial Pain, Instituto Superior de Saúde Egas Moniz, Monte da Caparica, Portugal.
OBJECTIVES: Using the push-out technique, this study compared the influence of different composite insertion techniques in Class I cavities on the regional shear bond strength to lateral walls. MATERIALS AND METHOD: Standardized Class I cavities were prepared on the occlusal surface of 60 freshly extracted third molars, which were randomly assigned to one of five groups (n = 10). The cavities were bonded with the self-etch adhesive AdheSE and restored with Tetric Ceram resin composite by one of five techniques: G1, incremental technique (four oblique layers); G2, flowable composite as liner and bulk technique; G3, bulk technique and G4, light cone technique. The total-etch adhesive (Single Bond) and incremental technique were used as the control procedure. Each specimen was sectioned perpendicular to the long axis of the tooth in 1 mm-thick dentin slices. A push-out test was performed to measure regional bond strengths and identify the type of failure. Two additional teeth per group were prepared for the morphological interface study using scanning electron microscopy. RESULTS: Differences between the groups were tested by one-way ANOVA and Scheffé post hoc test (F = 29.635, p < 0.001). The highest shear bond strength values were obtained with the incremental technique, regardless of the adhesive used. Significant differences in bond strength to superficial and deep dentin were only found when a total-etch adhesive was used (Single Bond). CONCLUSIONS: Use of the incremental technique with total-etch or self-etch adhesives is the most effective method of inserting resin-based composites in large Class I cavities.
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