Comparative Evaluation of Different Natural Antioxidants on The Immediate Bond Strength of Composite Resin to Bleached Enamel: An In-Vitro Study

Background: Bleaching is considered an effective and conservative way to lighten the discolored teeth. Nevertheless, if adhesive restorations are carried out promptly, it can potentially reduce the bond strength of the enamel. As a result, the compromised bond strength of bleached enamel can be restored by employing antioxidant agents Objective: To evaluate the effect of different natural antioxidants on the immediate bond strength of composite resin to bleached enamel. Materials and Methods: Sixty extracted human maxillary incisors were divided into six groups of ten teeth in each group: - Group I: Negative control - no bleaching and no antioxidant, Group II: Positive control - Bleaching without antioxidant, Group III: Bleaching with application of 10 % Sodium ascorbate, Group IV: Bleaching with application of 10 % Proanthocyanidin, and Group V: Bleaching with application of 1 % Resveratrol, Group VI: Bleaching with application of 10% Beta-carotene. Micro-shear bond strength of the specimens were tested under universal testing machine. Statistical Analysis: Data were statistically analyzed using one-way ANOVA and Tukey’ s Post Hoc intergroup comparison test. Results: The highest and lowest mean shear bond strength values were observed in Group I (4. 6 ± 0.46) and Group II (2.04 ± 0. 45), respectively. Mean shear bond strength of Group III, IV, V and VI showed higher statistically significant difference compared to Group II (p<0.05). No significant difference was found among the experimental groups III, IV, V and VI (P> 0. 05). Conclusion: Based on the results of the present study, it can be inferred that the use of antioxidants on bleached enamel prior to composite restoration effectively restored the immediate bond strength.