Effect of coffee staining and simulated oral hygiene methods on the color and translucency of a nanoceramic resin

OBJECTIVE: Evaluate the color and translucency of a nanoceramic resin subjected to hygiene practices and immersion in coffee over time. MATERIALS AND METHODS: Specimens (n = 80, HT and LT, 0.5-mm thick) of a nanoceramic resin were obtained and were divided in groups according to the simulated oral hygiene: no intervention (NT), brushing with an electric brush and water (BN), brushing with an electric brush and toothpaste for 10 s (BT), and immersion in mouthwash for 30 s (MW). Oral hygiene practices were repeated after staining in coffee solution for 15, 48, 336, 1440, 8640, and 35,040 min. Spectral wavelengths were recorded with a spectrophotometer at each time. ∆E00, ∆L', ∆C', ∆H', and TP00 were calculated by CIEDE2000 and were evaluated by 2-way ANOVA, repeated measures ANOVA, and Tukey's HSD test (α = 0.05). RESULTS: ANOVA showed significance among factors for ΔE00 (p < 0.05), with higher ΔE00 for NT-HT (11.7) and NT-LT (11.2). After T6 (2-year simulation), the lowest values were found for BT-HT (5.3) and BT-LT (4.9). All groups showed a reduction in lightness and translucency and increased chroma and hue. However, the smallest variations were found in the BT groups (p < 0.05). CONCLUSIONS: Brushing with toothpaste effectively minimized the color change of NCRs caused by coffee staining. CLINICAL SIGNIFICANCE: Oral hygiene practices, such as brushing with toothpaste, might be important to minimize staining of nanoceramic resin restorations, especially in patients who frequently consume coffee.