EFFECTS OF HYDROGEN PEROXIDE-BASED MOUTHWASHES ON COLOUR CHANGES OF STAINED DIRECT COMPOSITE RESINS RESTORATIONS

Abstract

Aim: The aim of this study was to evaluate the effect of three mouthwashes on colour changes of two different composite resins stained with tea. Materials and Methods: Twenty Five specimens were prepared for each of the two composite resins Filtek Z350 (Z350) and Polofil Supra (PS), and the specimens were then stained in a tea solution. Each composite group was randomly divided into five subgroups (n = 5) according to the immersion solution: Distilled water (DW) (negative control); Crest 3D White mouthwash (CR); Listerine whitening mouthwash (LS): Colgate Optic White Mouthwash(CO), and Opalescence PF gel (OP) (16% carbamide peroxide, positive control). The colour of the specimens was measured with a spectrophotometer according to the CIEL*a*b* colour scale at baseline, after staining. and on the 7th, 28th, and 56th days of the treatment period. The colour differences (ΔΕ) were analysed with a two way ANOVA followed by Tukey's test (P < 0.05). Results: The discoloration of the specimens after immersion in the mouthwashes decreased significantly over time. Only the staining of the Z350 specimens treated with CR, LS, and OP decreased to a clinically acceptable level at the end-treatment period. Conclusion: The nanohybrid composite (2350) showed the least discoloration, followed by the microhybrid (Polofil Supra).