Journal of AdvancedMedical and Dental Sciences Research

Background: The application of antioxidant agents after bleaching has been recommended as a way to reduce the waiting period between bleaching and restorative procedure by eliminating the reactive oxygen from the dental substrate. The present study was conducted to assess the effect of antioxidants on the bond strength of composite resin to bleached enamel. Materials & Methods: The present study was conducted on 30 freshly extracted maxillary premolars. Each crown was sectioned with carbide disc longitudinally and a total of sixty enamel specimens were obtained. The specimens were divided into 4 groups. Group I (15) was control group (No bleaching). Group IIa (15) specimens were bleached with 15% carbamide peroxide, group IIb (15) specimens were bleached with 15% carbamide peroxide followed by application of 10% sodium ascorbate gel, group IIc (15) were bleached with 15% carbamide peroxide followed by application of 5% PA agent. The shear bond strength assessment was done using universal testing machine. Results: The mean bond strength in group I was 24.6 MPa, in group II was 15.2 MPa, in group II b was 27.3 MPa and in group II c was 32.1 MPa. The difference was significant (P< 0.05). Conclusion: Authors found that the use of antioxidant before bonding procedures on bleached enamel completely neutralizes the deleterious effects of bleaching and increases the bond strength significantly. Key words: Bleaching, bond strength, universal testing machine