Comparison of Color Change of Silorane and Methacrylate-Based Composites Due To Bleaching

Background and aim: bleaching agents differently affect the color of composite restorations. this study aimed to assess the effect of two different bleaching agents on color change of silorane-based and two types of methacrylate-based composites. materials and methods: this in-vitro study was conducted on 18 disc-shaped specimens measuring 10×2mm made of a3 shade of z250, z350 and p90 composites. the specimens were randomly divided into three groups (n=6). group one or control samples were stored in distilled water. groups two and three were subjected to bleaching with 16% and 35% carbamide peroxide (cp) (kimia, chemident, iran). color parameters of specimens were measured before and after bleaching using the cie l*a*b* system and a spectrophotometer. data were analyzed using repeated measures anova and tukey’s hsd test for multiple comparisons. results: the mean and standard deviation (sd) of total color change (δe) of z250 in distilled water, 16% carbamide peroxide and 35% carbamide peroxide was 3.48±1.43, 4.55±1.7 and 4.17±1.9, respectively. these values were 4.33±2.41, 4.94±2.23 and 4.25±1.65 for z350 and 4.97±2.47, 5.28±1.67 and 3.41±2.26 for p90, respectively. conclusion: in general, the color change of microhybrid, nanofilled and silorane-based composites following bleaching with different bleaching agents was clinically perceivable.