Effect of Different Light Sources on the Color of All-ceramics

Objectives: All ceramic restorations allow superior translucency and can be used in areas of high esthetic demand. A challenge in the success of these restorations is color assessment and reproducibility. The available shade guides, in addition to minor differences in light conditions, have been found to dramatically affect the outcome of restoration color and the production of an acceptable color match. The aim of this in vitro study was to evaluate the effect of different light sources on the color of leucite-glass ceramics. Methods: 24 ceramic disks were fabricated with IPS Empress Esthetic porcelain according to the manufacturer's instructions and randomly divided into 2 groups of 12 each (10 mm diameter-0.5 mm thickness and 10 mm diameter-1 mm thickness). A digital spectrophotometer were used under 5 different light sources (Fluorescent lamp, dental unit lamp, daylight, Ultraviolet light and no light) to examine the color. The CIE Lab values were recorded and statistical analysis was performed using two-way analysis of variance and Tukey HSD tests. Results: Statistical analysis indicated that L* values were significantly affected by the light source and the ceramic thickness (P<0.05). Mean a* values were significantly affected by the light source (p<0.05), but not affected by the ceramic thickness (p>0.05). Mean b* values were significantly affected by the light source and the ceramic thickness (p<0.05). Conclusion: When L*a*b* values were significantly affected by the light source, the digital spectrophotometer showed the same color shade number with all light sources.