Color Stability and Surface Roughness of Esthetic Resin Composites Following Simulated Toothbrushing with Whitening Toothpastes

Abstract

This in vitro study aimed to evaluate the effects of two whitening toothpastes with different mechanisms and one non-whitening, low-abrasivity toothpaste on the color stability and surface roughness of three anterior esthetic resin composites after coffee staining. Ninety disc-shaped specimens (2 mm × 6 mm) were prepared from three resin composites: Filtek Ultimate, Estelite Sigma Quick, and Neo Spectra ST Effects (n=30 each). After polishing, specimens were stored in distilled water for 24 hours at 37°C. For staining, the specimens were fully immersed in a freshly prepared coffee solution (3.6 g/300 ml) at room temperature for six consecutive days. The solution was renewed every 24 hours to ensure a constant concentration of chromogens, simulating six months of clinical coffee consumption. Color and surface roughness were measured at baseline and after staining. Each composite group was then divided into three subgroups (n=10) and brushed in a simulator with one of three toothpastes—Sensodyne Promine, Opalescence Whitening, or R.O.C.S. Sensation Whitening—for a total of 30 minutes at a 200 g load. Final measurements were taken, and color change (∆E₀₀) and surface roughness change (∆Ra) were calculated. Data were analyzed using ANOVA and Tukey HSD (p<0.05). Composite type significantly influenced color change after staining (p<0.05), with Estelite Sigma Quick showing the highest ∆E00 values. Toothpaste type also significantly affected color change (p<0.05), with Opalescence Whitening producing greater whitening in certain composite groups. All experimental groups exhibited ∆E₀₀ values above the clinical acceptability threshold (∆E₀₀> 1.8). Surface roughness increased significantly within some groups after brushing, but there were no significant intergroup differences between toothpaste types (p>0.05).