Effect of Chitosan Nanoparticle as an Antioxidant Material on Shear Bond Strength of Composite Resin to Enamel after External Bleaching

Abstract

BACKGROUND: If composite resin restoration is required following external bleaching treatment, a waiting period of between 1 and 3 weeks is needed to avoid restoration failure. However, patients usually need faster treatment. AIM: This study aimed to investigate the effect of chitosan nanoparticles as an antioxidant material on the shear bond strength (SBS) of composite resin restorations to enamel after external bleaching. METHODS: Thirty premolars were used in this study and randomly assigned into four groups of six samples, Group 1, no bleaching – no antioxidant, Group 2, bleaching – composite restoration, Group 3, bleaching – waiting 2 weeks – composite restoration, Group 4, bleaching – sodium ascorbate – composite restoration, Group 5, bleaching – chitosan nanoparticles – composite restoration. The SBS was tested with a universal testing machine. One-way analysis of variance and the Turkey’s test were used for statistical data analysis (p < 0.05). RESULTS: The group that applied chitosan nanoparticles to the teeth previously bleached and then restored with composite resin resulted in similar SBS as the other groups (p > 0.05), except for the group that was bleached and directly restored with composite resin (p = 0.000). CONCLUSION: The chitosan nanoparticle has the potential as an antioxidant material since it produces similar SBS to composite resin restorations on enamel after external bleaching than the other groups.