Effect of three mechanical surface treatments on the repair bond strength of the silorane-based composite resin

Abstract

Successful repair of composite resins requires a proper interfacial bond between the old and the new composite resins. The aim of the present study was to compare the effect of three mechanical surface treatments, including diamond bur, air abrasion, and Er,Cr:YSGG laser on the repair bond strength of the silorane-based Composite resin. Materials and methods:68 cylindrical composite resin specimens (Filtek silorane, 3M,ESPE, USA) were fabricated and randomly divided into 4 groups: group 1 (control group) without any mechanical surface treatment, groups 2-4 were treated with air abrasion, Er,Cr:YSGG laser, and diamond bur, respectively. Also, a positive control group (group 5) was assigned in order to measure cohesive strength. The topographical effects of surface treatments were characterized by SEM. Silorane bonding agent was used in groups 2-4 before adding the composite. After placing the new layer of composite resin (Filtek Silorane), on treated surface of samples shear bond strength values were measured and data was analyzed with one-way ANOVA and a post hoc Tukey test at a significance level of =0.05. Results: The highest and lowest shear strength values were recorded in groups 5 and 2, respectively. In laser treated groups, there were statistically significant differences in shear strength values between study groups(p<0.001);however, there were no significant differences between groups 1and 2 (P=0.98) and groups 3and 4 (P=0.97). Conclusion: Surface treatments using Er,Cr:YSGG laser and diamond bur were effective for silorane based composite repair.