Effect of surface treatment with Er,Cr

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 surface treatment with CO2, Nd: YAG and Er, Cr: YSGG lasers on repair shear strength of a silorane-based composite resin. Materials and methods: Sixty eight cylindrical samples of a silorane-based composite resin (Filtek Silorane) were prepared and randomly divided into 4 groups as follows: group 1: without surface treatment; groups 2, 3 and 4 with surface preparations using Er, Cr: YSGG, Nd: YAG, CO2, and lasers, respectively. The topographic effects of each of the surface preparation methods were evaluated under an electron microscope. A positive control group (group 5) was assigned in order to measure cohesive strength. 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 1, respectively. In laser treated groups, there were statistically significant differences in shear strength values between group 1 and other groups(p<0.001) and between group 2 and groups 3 and 4 (P=0.008 & P=0.001); however, there were no significant differences between groups 3 and 4 (P=0.93). Conclusion: Shear repair bond strength of siloran base composite is higher by surface treatment with laser under study compared with no surface treated and effect of Er,Cr:YSGG is more prominent.