Color stability of three resin cements after accelerated aging

An important factor in the long term success of the luting agent in aesthetic restorations is the color stability. Purpose: To evaluate the color stability of three different dual cured resin cements after accelerated aging. Materials and Methods: Twenty four specimens disks (15mm diameter and 0.5mm thick) of three dual cured resin cements RelyX ARC (3M), Calibra (Densply) and Variolink II (Ivoclar) were evaluated in color stability after an accelerated aging process (300h, UV light, 43±1°C; 50%HR, 18min water spray every two hours). The samples were analyzed with an spectrophotometer (CIELab system) before and after accelerated aging to obtain ΔL*, Δb* and ΔE*. The values were calculated and analyzed by ANOVA and Tukey test. Results: In ΔL significant differences were found for Calibra and Variolink II (P£0.001) and equally found for all the three cements in Δb* (P£0.001) before and after accelerated aging. ΔEab* showed an important difference too (P£0.001). Additionally, the samples were analyzed under Scanning Electronic microscope, showing a superficial degradation of the organic matrix specially Calibra. Conclusions: There was a significant change in color of the dual cured resin cements after accelerated aging.