RESUMEN
PURPOSE: To compare the color stability of a microhybrid and two nanocomposites after exposure to common soft drinks among adolescents. METHODS: Ninety discs were prepared from a microhybrid (Filtek Z250) and two nanocomposites (Filtek Z350 and Tetric N-Ceram) (n = 30 each). Six discs from each material were then immersed in one of five drinks (iced tea, sports drink, orange juice, cola, and distilled water) for 15 days. Color measurement was performed at baseline and after 15 days using a spectrophotometer according to the CIE L*a*b* system, and the change in color values as well as total color change (ΔE) was calculated and compared. ANOVA and Tukey's HSD test were used to analyze the data (p < 0.05). RESULTS: Significant change in color values and total color (ΔE > 3.3) was observed in the composite materials after immersion in the soft drinks compared to immersion in distilled water (ΔE < 3.3). The highest mean values were those of Filtek Z350, being significantly different from the rest of the materials. Independent of the composite material, iced tea resulted in the highest mean values, being significantly different from the rest of the drinks (p < 0.05). CONCLUSION: All soft drinks resulted in clinically unacceptable discoloration of the composite materials with maximum discoloration being that following immersion of composite materials, particularly Filtek Z350, in iced tea. Consequently, in dental practice, adolescents should be asked about their consumption of soft drinks, particularly iced tea, and made aware of their potential to discolor composite restorations if they are to receive them.