Color Change of a Composite: Influence of Beverages and Brushing

Objective: This study evaluated the influence of beverages on the color change of a composite resin, associated or not to brushing. Methods: 120 disks (10mm-øX2mm-thick) of composite resin (Filtek-Z250) were prepared (single increment; 20-s light-curing) and polished after 24h. Initial color was measured and specimens were randomly assigned into four groups (red wine, soft drink, sugar cane spirit, or artificial saliva – control) and three subgroups (without brushing; brushing with Colgate, or brushing with Close Up Whitening). Specimens were immersed in the beverage 5x/day, for 5', over 30 days, being two subgroups brushed at the end of every day (120 moving/day). Color was measured at the 15^th and 30^th days of immersion. After the immersion period, specimens were stored in artificial saliva for 7 days, when their surfaces were polished and immediately assessed by color. Color change was analyzed by ΔE, ΔL, Δa, and Δb values. Data were submitted to ANOVA and Fisher's tests (a=5%). Results: Color change values were statistically different after immersion; red wine promoted the highest alteration, followed by soft drink and sugar cane spirit, which presented similar results among them and different to saliva. No difference was observed with or without brushing independently of the toothpaste. At 30^th day, specimens exhibited a color change higher than 15^th day; after polishing, the color of the specimens was similar to 15^th day. Conclusions: Color change of the composite resin was influenced only by the beverages and brushing didn't affect the analyzed property. The re-polishment was not sufficient to promote the return of the specimens' color to their initial values.