Effect of Smear Layer Deproteinization on Bond Strength of Self-Adhesive Resin Cement to Dentin

Abstract

Aim: The aim of this study is to examine the effect of smear layer deproteinization using sodium hypochlorite and hypochlorous acid solutions on the bond strength of self-adhesive resin cement to dentin. Materials and Method: A total of 56 extracted human molars were used in the study. A uniform smear layer was formed with abrasives on the dentinal surfaces of the teeth. Four different experimental groups were formed: no oxidizing agent was applied (control), sodium hypochlorite was applied for 30 seconds (NaOCl), hypochlorous acid was applied for 15 seconds (HOCl-15) and 30 seconds were applied (HOCl-30). Prepared composite blocks were cemented to dentin surfaces with self-adhesive resin cement (TotalCem, Itena, Paris, France). Shear bond strength test was applied to the samples in a universal testing device. Dentin surfaces were examined by scanning electron microscopy (FE-SEM, Mira 3 XMU, Tescan, Brno, Czech Republic). One-way Analysis of Variance (ANOVA) and post-hoc Tukey HSD tests were used for statistical analysis (p˂0.05). Results: It was determined that the bond strength in the HOCl-15 group was significantly higher than the other study groups (p˂0.05). Conclusion: Deproteinization of the smear layer with HOCl is thought to increase the bond strength between the tooth and the self-adhesive resin cement.