Comparison of the effect of different metal alloys on the esthetic appearance of dentin porcelain

The purpose of this study was to examine the effect of aurofilm masking agents applied to various metal alloys on the color of porcelain in metal-ceramic restorations (MCRs). The study was conducted with 2 different base-metal alloys (Ni-Cr, Co-Cr) and 2 different noble alloys (Pd-based, Au-Pd) used for MCRs, as well as 1 high noble alloy (Au-based) that served as a control group. Eight experimental groups (n=7) and 1 control group were used in this study. An aurofilm masking agent was applied to 4 groups (AuPdM, PdM, CoCr, NiCrM). Opaque porcelain and dentin body porcelain were applied to all groups. CIEL*a*b* color coordinates were measured. The Pd group had the highest mean a* value (-5.82); however, in comparison to the control group, the differences in a* values were statistically significant only for the Cr-Co alloy groups (CoCr and CoCrM). The Pd group had the highest mean b* value (7.89). The ΔE value (2.13) of the CoCr group was significantly higher than all other alloy groups. Metal alloy substrate and aurofilm masking agents significantly affected the color of porcelain MCRs. However, color differences between base-metal and noble alloys and the control group were within clinically acceptable limits (ΔE<3.5).