Evaluation of the color stability of resin composites subjected to artificial aging procedures: immersion in different solutions, brushing, and thermal cycling.

The aim of this in vitro study was to evaluate the color change of resin composites with different filler contents subjected to immersion in different solutions, brushing, and thermal aging procedures. A total of 320 samples were prepared using 4 different flowable and 4 different conventional resin composites (n = 40). The samples were separated into 4 subgroups according to the solution to be used (wine, coffee, tea, or distilled water) and then immersed in the solutions for 12 days. All samples were subjected to 10,000 cycles of brushing and 10,000 cycles of thermal cycling procedures. ∆E values were calculated according to CIEDE2000 and CIELab color systems. For statistical analysis, the 3-way analysis of variance, the Tukey test, and the intraclass correlation coefficient were used. The significance level was taken as P < 0.05. Mean color change values differed significantly according to the solution, type of resin composite, and their interactions (P < 0.001). The values of the highest color change were obtained in wine, according to solutions, and conventional according to type. The filler content, viscosity, solutions to which they are subjected and their interactions with each other are effective factors in the color stability of restorative materials. The most effective factor in the color change of resin composites was the solution.