Abstract:

Objective　The purpose of this study was to evaluate the color changes of gingival porcelain through varying thick- ness and shade of porcelain of ceramometal restorations.Methods　In this study a spectrophotometer (PR-650) was used for col- or analysis. The color changes of dentin porcelain and gingival porcelain with three varied thickness (0·3 mm, 0·6 mm and 0·9 mm) were investigated. In addition, the color variances of Shofu vintage porcelain shade A2, A3and B2were tested.Results 　The results showed that decreased L* value of ceramometal restorations and increased a* value were due to the increase of the gingival porcelain thickness, color measurements showed the same trend as the increased dentin porcelain thickness and the opaque and dentin porcelain with different color affected the appearance of gingival porcelain.Conclusion　The color of gingival porcelain would be changed with the differences of thickness and shade of porcelain of ceramometal restorations.

Key words: porcelain, fixed restoration, color