Susceptibility to discoloration of dental restorative materials containing dimethacrylate resin after bleaching

The aim of this study is to compare the susceptibility to discoloration of dental restorative materials containing dimethacrylate resin after bleaching. In this study, resin-modified glass ionomer, polyacid-modified composite resin, giomer, posterior composite resin, anterior composite resin, bulk fill composite resin, flowable bulk fill composite resin, ormocer, indirect composite resin and hybrid ceramics were used as restorative material containing dimethacrylate resin. 20 samples were prepared from each material in accordance with the manufacturer's instructions. After the baseline colors are measured, the samples were randomly divided into four subgroups as office bleaching, home bleaching and a separate control group for each type bleaching method. Then, the samples were bleached and colored. Color measurements of the samples were repeated after exposure to bleaching and coloring. Then, ΔE00 and whiteness index (WI_D) were calculated. Data were analyzed using Paired-Samples T Test, two-way ANOVA, Repeated Measures ANOVA and Tukey post-hoc tests. Statistical significance level was taken as p < 0.05. In terms of bleaching systems, Opalescence Boost was found to cause more whitening in materials but more discoloration (p < 0.05). In terms of materials, it was found that the most susceptible materials to coloration were Clearfil Majesty Posterior, Filtek Bulk Fill Posterior Restorative, Filtek Bulk Fill Flowable and Fuji II LC, while the least susceptible materials were CAD/CAM materials (p < 0.05). The bleaching process increases the susceptibility to coloration of materials containing dimethacrylate resin.