The effect of different zirconia core staining methods on the optical properties of ceramic restorations

Abstract

Introduction: One of the important factors in the success of ceramic restorations, in addition to having the desired physical and mechanical properties, is the problem of their color and similarity with the natural color of teeth. Due to the whiteness and opacity of zirconia, different colored zirconia frameworks have been used to achieve better and more natural color properties. However, so far no study has been conducted to compare the optical properties among the various zirconia staining methods. The aim of the present study was to compare the optical properties of restorations made with zirconia frames painted with different techniques. Methods and Materials: In this experimental laboratory study, 40 discs (10 discs in each study group) were made. In monolithic zirconia A3 (group 1) the Zolid fx preshades blocks with 1.8 mm zirconia, in A3 color blind (Group II) the Zolid fx preshades blocks with 1 mm zirconia and 0.8 mm porcelain in A3 GC Initial color, in translucent painted in Dark A3 (group 3) the Zolid fx white blocks with 1 mm zirconia and 0.8 mm porcelain in A3 GC Initial color, and in translucent blind (group 4) the Zolid fx white blocks with 1 mm zirconia and 0.8 mm porcelain in A3 GC Initial color were used. To measure the color properties, a spectrophotometer was used to compare the colors of the two coloring methods (second, third and fourth groups compared to the first group). Results: In this study, the mean ∆E of the second group was 4.7, the third group was 7, and the fourth group was 9.6. The amount of color difference (∆E) between the first and second groups was less than the other groups. Conclusion: A3 colored zirconia blind can be used in making restorations as a suitable option instead of monolithic zirconia A3 due to its proximity to the natural color of the teeth.