Comparative evaluation of micro-tensile bond strength of one-step self-etching adhesive systems

Purpose: The aim of this study was to assess micro-tensile bond strength values to dentin of four different one-step self-etching adhesive systems in vitro in a comparative manner. Materials and Methods: In the present study, 20 caries-free human molar teeth were used. Occlusal surfaces were removed to achieve a uniform dentin surface under water cooling by using a low-speed diamond saw. The dentin surfaces obtained were abraded for one minute by using 600-grit silicon carbide papers. Then, the teeth were randomly assigned into four groups (n = 5). For restoration of teeth prepared, four different one-step self-etching adhesive systems, including Clearfil S 3 Bond Plus, Clearfil S 3 Bond, Xeno V Bond and Adper Easy Bond were used according to manufacturer′s instructions. A 4 mm thick of composite resin crown (ClearfilAP-X) was applied to surfaces pre-treated with bonding agent. Samples were stored in distilled water at 37°C for 24 hours until micro-tensile bond strength tests were performed. Statistical analyses were performed by using one-way ANOVA and post-hoc Tukey tests (α =0.05). Fracture surfaces were evaluated using a stereomicroscope. Results: Significant differences were observed in bond strength to dentin among one-step self-etching adhesive systems (P < 0.05). The highest bond strength was achieved by Clearfil S 3 Bond Plus system (P < 0.05). No significant difference was observed in bond strength among other groups (P > 0.05). Conclusion: There were differences between bond strength values of tested one-step self-etch adhesives. Clearfil S 3 Bond Plus exhibited higher values.