Color stability of nanohybrid composite resins in drinks

ABSTRACT

Aim: The objective of this study was to evaluate the effects of solutions on the color stability of nanohybrid composite resins. Methods: The experimental sample consisted of 90 composite specimens (Beautifil II; Z350XT; Premisa), divided into three subgroups (n=10) according to the solutions (matte tea; lemon flavor isotonic drink; artificial saliva). The specimens were immersed in the solutions (5 mL/specimen) while stirring for 5 minutes, four times a day, with 1-hour intervals, repeated for 15 days. The color of the specimens was analyzed before (baseline) and after the 15th day of cycling using the CIELAB system. Data were analyzed using the two-way analysis of variance (ANOVA) and Tukey's test (α=5%). Results: Different behaviors were observed among resins. Beautifil II presented the highest color change (∆E=4.18) and less color stability, statistically different from the others (p<.05). The solutions also presented different behaviors. The lemon flavor isotonic drink (∆E=3.95) promoted the highest color change, statistically different from saliva (∆E=2.75; p<.05). The interaction between Beautifil II and isotonic drink became even more evident and significant (p<.05). Conclusion: The isotonic drink is the solution that most affected the resins, and Beautifil II presents the worst color stability