Comparative evaluation of reversal of shear bond strength on bleached enamel-resin nanocomposite using antioxidants – sodium ascorbate, salicylic acid & N-acetyl cysteine

Abstract

Aim: The aim of this study was to compare the reversal of shear bond strength of bleached enamel using 3 antioxidant agents. Methods and Materials: 60 labial enamel blocks of maxillary central incisors were prepared, divided into six groups (n=10). Group I is control group without bleaching and without antioxidants, all the other groups were bleached with 30% carbamide peroxide. Group II, composite bonding done immediately without antioxidants application, Group III, composite bonding done after 7 days of storage in artificial saliva without receiving antioxidants. Group IV, bleached enamel receive sodium ascorbate (SA) antioxidant application for 10 minutes, followed with composite bonding immediately, similarly Group V and VI bleached enamel samples received salicylicacid(SAC) and N-acetylcysteine(NAC) antioxidants application for 10 minutes and composite bonding immediately. All the teeth were subjected to shear bond testing in universal testing machine. Statistical analysis used: The shear bond strength data was analyzed by ANOVA test and multiple comparisons by Tukey’s post-hoc tests at a significance level of P < 0·05. Results: The result of this study showed that for shear bond strength, unbleached normal enamel (group I) showed highest SBS value among all the groups.