Comparative Evaluation of the Microtensile Bond strength of composite resin to Bleached Enamel: An In vitro Experimental Study

Abstract
Aim: Comparative evaluation of the effectiveness of 10% sodium ascorbate solution and delayed treatment on the microtensile bond strength of nanocomposite to bleached enamel using two step etch and rinse and self-etch adhesive technique. Materials and methods: Forty extracted human maxillary central incisors were decoronated, and the crown portion was embedded in acrylic resin with the buccal surface facing upwards. The specimens were randomly allocated to four groups which were further sub-divided into two groups according to the adhesion protocol. Group I- (control group): No bleaching followed by restoration. Group II: Bleaching followed by immediate restoration. Group III: Bleaching followed by surface treatment with 10 % sodium ascorbate for 30 mins followed by restoration. Group IV: Bleaching followed by restoration after 14 days. Result: Statistically significant differences were found between microtensile bond strength of bleached enamel with surface treatment with 10% sodium ascorbate solution and no surface treatment group. Conclusion: Bleaching followed by surface treatment with 10 % sodium ascorbate for 30 mins followed by restoration showed similar strength as compared the control group.