Influence of core color on final shade reproduction of zirconia crown in single central incisor situation – An in vivo study

BACKGROUNDA lot of shaded zirconia blocks are being introduced into the market. Their effect on the final shade of the restoration is yet uncertain. MATERIAL AND METHODSTwenty-four zirconia crowns were fabricated for 8 patients who needed to restore a single maxillary central incisor, and divided into 3 groups according to the color and type of the zirconia (Zr) used (white Zr core, colored Zr core, and monolithic high translucency (ht) Zr crowns). Using Easyshade spectrophotometer, delta E color difference was calculated between fabricated crown and adjacent tooth. The ΔEs obtained were assessed based on 1.6 ΔE which represented the color difference that could not be detected by the human eye and considered clinically acceptable. RESULTSNo statistically significant values were found between the 3 groups related to different Zr color and type. CONCLUSIONSWithin the limitations of this study, it could be concluded that the shade of the zirconia blank had no significant effect on the final color of the crown. This raises reasonable doubt about the necessity to use colored zirconia blanks or use of dip-in solutions. The clinical implications were that, there was no need to use colored zirconia cores to get more esthetically pleasing restorations with respect to color perception. The use of monolithic high translucent zirconia crowns gained the advantages of high translucency and color reproduction. Key words:Zirconia, easyshade, monolithic, spectrophotometer, delta E.