COLOR COMPARISON OF VARIOUS POST SYSTEMS WITH EMPRESS 2 CROWNS

포스트의 종류에 따른 Empress 2 도재관의 색상에 관한 비교연구

Development of new ceramics and esthetic needs of patients increase the use of all ceramic restorations. Fractured teeth often need metal post and core as foundation for final restoration. When all ceramic restorations are planned, metal post and core may lead to compromised esthetics because of opacity and gray color of metal post and core. Many techniques have been proposed to solve this problem such as application of an opaque porcelain to the metal core or all ceramic post and core. This study was performed to evaluate effect on color of Empress 2 crown according to various post systems. Color was evaluated by the CIE $L^*a^*b^*$ systems and measured by spectrophotometer (Model CM-3500, Minolta, Japan). Specimens were divided into 4 groups as follows Group 1 : gold cast post specimen + Empress 2 crown specimen Group 2 : application of an opaque porcelain to gold cast post specimen + Empress 2 crown specimen Group 3 : cosmopost specimen + Empress 2 crown specimen Group 4 : In-ceram post specimen + Empress 2 crown specimen. The results obtained as follows, 1. $L^*$ Values showed that group 2, 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 2. $a^*$ Values and $b^*$ values also showed that group 2. 3, 4 were higher than group 1 with significant difference and group 2, 3, 4 were not significantly different. 3. ${\Delta}E^* ab$ Values showed that ${\Delta}E^* ab$ 3 was the highest value and ${\Delta}E^* ab$ 5 was the lowest value.