Evaluation Of The Effect Of Cement Shade And Accelerated Artificial Aging On Color Stability Of Cadcam Resin-Matrix Ceramics: An In Vitro Study

Abstract

Aim: This study was conducted to examine the effect of cementation and artificial aging on color stability of three resin-matrix ceramic CAD/CAM materials.

Methodology: About 12 x 14 x 1.0 mm rectangular-shaped specimens were prepared from a hybrid ceramic (Vita Enamic), a hybrid resin nano-ceramic (Cerasmart), and a resin nano-ceramic (Lava Ultimate) (n = 30). Specimens of each material were luted with three shades of a resin cement in 0.2 mm thickness (Variolink N; A1, Bleach XL and Transparent), followed by artificial aging step (n = 10). Color coordinates were measured in each step with a colorimeter. Color differences (ΔE₀₀) were calculated from CIEDE2000 formula, and statistically analyzed with one-way ANOVA and paired t-tests.

Results: Artificially aging the specimens resulted in a significant increase in ΔE00 regardless of shade and material type (p < 0.05). No significant color differences due to artificial aging were detected when the three shades were compared for only Vita Enamic samples (p > 0.05). Luting with different shades of resin cement did not result in a statistical difference in ΔE₀₀ between the restorative materials (p < 0.05) except for Cerasmart luted with Bleach XL (p < 0.05); however, artificial aging led to statistically significant differences between the materials when luted with the same shade of the resin cement (p < 0.05).

Conclusion: The final color of resin-matrix ceramics is affected by the resin cement shade and artificial aging.