LABORATORY EVALUATION OF TARGIS COLOR STABILITY IN COMPARISON WITH PORCELAIN AND COMPOSITE BY COLORIMETER

Introduction: Color stability is crucial for the success of any restorative material. Despite composites, color stability of ceromers has not been studied widely. The purpose of this study was evaluation of color stability of one type of ceromers and comparing it with porcelain and composite. Materials & Methods: In this invitro experimental study, one type of ceromers (targis), a light cured direct composite (tetric ceram) and a porcelain (vita) were chosen. The samples were evaluated in CIELAB color order system by a colorimeter in 3 stages: before UV exposure, after 100 hours UV exposure and after 200 hours UV exposures. l*, a* and b* peculiarities and their changes in examination steps were calculated. The results were analyzed by ANOVA and LSD statistical tests. Results: The results revealed the porcelain and targis had the highest and lowest color stability after 100 (P=0.05) and 200 (P=0.014) hours periods, respectively. In comparison among the different colors of ceromers, C3 and D3 had the highest and the lowest color stability respectively (P= 0.001 in 100 and P= 0.008 in 200 hours). In all of studing groups, the final color change were clinically acceptable. Conclusion: All of the groups revealed acceptable color stability and among them porcelain had the best characteristics. Key words: Targis, color stability, colorimeter.