فهرست نشریات علمی دسترسی آزاد ایران

Objective: This study evaluated the effects of 2% chlorhexidine (CHX) and Er:YAG laser on the shear bond strength (SBS) of resin composite to affected dentin using two adhesive systems.Methods: Sixty extracted third molars were randomly assigned to three disinfection groups (control, 2% CHX, and Er:YAG laser). Each disinfection group was further divided into two subgroups based on the adhesive system used (an etch-and-rinse or a universal self-etch system), yielding a total of six groups (n=10). After caries excavation, dentin surfaces were treated according to the assigned disinfection and adhesive protocols. The resin composite was then applied to the treated surface using a cylindrical mold. Samples underwent 10,000 thermal cycles, followed by shear bond strength (SBS) testing and failure mode analysis. Data were analyzed using two-way ANOVA and chi-square test at the significance level of P < 0.05.Results: ANOVA revealed no significant differences in mean bond strength among the disinfection groups with either adhesive system (P > 0.05).  However, the etch-and-rinse adhesive showed significantly higher SBS compared to the universal self-etch adhesive across all disinfection groups (P < 0.05). Chi-square analysis revealed no significant differences in failure modes among the groups (P = 0.71).Conclusions: Disinfection of affected dentin with either Er:YAG laser or 2% CHX does not reduce the bond strength of adhesive systems. The etch-and-rinse adhesive consistently achieved higher SBS than the universal adhesive after dentin disinfection, suggesting that it may be preferred for clinical use.