Evaluation of the color stability of resin composites against new color changes following a whitening procedure using mouthwashes

AIM: The aim of this study is to assess whether coloured resin composites undergo greater colour changes following exposure to a colouring solution after the use of a whitening mouthwash. MATERIALS AND METHODS: Sixty composite discs (2 × 8 mm) were prepared and divided into three groups (n = 20). Each group was then randomly assigned to one of two different mouthwash groups (n = 10). The samples were then immersed in a coffee solution for 6 days. The samples were immersed in a whitening mouthwash solution for 24 h. The samples were then immersed in the coffee solution again for 6 days. ∆E values were calculated according to the CIEDE2000 color system. For statistical analysis, the Kolmogorov-Smirnov test, one-way ANOVA, and the LSD Post Hoc test were performed. The significance level was taken as P < 0.05. RESULTS: , the values for the OMN group were found to be significantly higher than those for both the EST and PAL groups (P < 0.001). CONCLUSION: In this study, which investigated whether coloured composite resins undergo further colour changes following exposure to a whitening mouthwash, varying degrees of colour change were observed in the composite resin samples. Re-exposure of the composite resins, which had changed colour following the use of a whitening mouthwash, to the colouring solution did not result in further colour change.