Comparative analysis on the precision fit of dental prosthesis between the variously fabricated copings of nickel-chromium alloy, titanium and zirconia ceramic

Precision fit of dental prostheses were compared between the four experimental groups of cast Ni-Cr alloy, cast titanium, milled titanium and milled zirconium by measuring and comparing the mean values of the marginal, axial, occlusal and overall coping-die gaps. The overall, axial and occlusal fit was most precise with the cast Ni-Cr alloy prosthesis. The biologically critical marginal fit was the most precise with the milled zirconium, thus suggesting that the copy-milled zirconia ceramic could serve as an alternative to the cast-metal prosthesis. The statistical variables, such as the groups and the regions, were in association with and had an interaction effect on the adaptability of the prostheses. The marginal gaps correlated with the axial gaps in the cast Ni-Cr alloy and milled titanium groups.