Effect of glutathione on bond strength of composite resin to enamel following extracoronal bleaching.

Background: Bleaching is a conservative treatment option to deliver esthetic smile makeover for discoloured tooth. Various concentration of bleaching agents can influence the bonding of the restoration to the tooth. Aims and Objectives: The aim of the study was to determine the effect of glutathione on bond strength of composite resin to enamel following extra coronal bleaching at two different time intervals. Materials and Methods: Forty molars were randomly assigned into four groups of ten each. Group A: Bleaching followed by immediate composite build up and no antioxidant application. Group B: bleaching followed by application of 20% Glutathione and immediate composite built-up was done. Group C: Bleaching followed by composite restoration after one week. Group D: Bleaching followed by application of 20% Glutathione before composite build up after one week. Shear bond strength was tested using a universal testing machine and fracture analysis was done using scanning electron microscope (SEM). Data were analyzed by one-way ANOVA and Post Hoc test with 95% level of significance (p<0.05). Results: Group D, which was treated with glutathione and restored after one week, revealed the highest shear bond strength compared to group B which was immediately restored following treatment with glutathione. Conclusion: Addition of 20% Glutathione as an antioxidant increased the shear bond strength of composite resin to enamel following extra-coronal bleaching using 40% hydrogen peroxide. [ABSTRACT FROM AUTHOR]