摘要
Objective :To evaluale the color change of the two-layer porcelain laminate veneer after adding veneering porcelain of differeat thickness to the 0.2mm thick aluminum oxide.Methods:Ten alumium axide disks were randomized into 2 groups.Each of five disks was veneered with Vita Lumin Shade B4 porcelain of thickness of 0.4mm and 0.6mm respectively.The L*a*b* color notations of the substrate covered with non-veneered disks and 2 thickness porcelain veneered disks were measured separtely and the color differences(ΔE) were calculated.Results:Statistically significant differences in color coordinates of dark substrates were recorded after the sustrate was covered by an aluminum oxide disk and also after the addition of veneering porcelain to the alumimum axide disks in group 1(P=0.0002) and group 2(P=0.0075) and between 2 groups(P=0.0001).Conclusion:The ability of masking underlying discoloration was increased and shifted to gray when the thickness of veneering porcelain increased.
Objective : To evaluate the color change of the two-layer porcelain laminate veneer after adding veneering porcelain of different thickness to the 0. 2 mm thick aluminum oxide. Methods : Ten aluminum oxide disks were randomized into 2 groups. Each of five disks was veneered with Vita Lumin Shade 54 porcelain of thickness 0/0.4 mm and 0. 6 mm respectively. The L'a'b* color notations of the substrate covered with nan-veneered disks and 2 thickness porcelain veneered disks were measured separately and the color differences (AE) were calculated. Results ?Statistically significant differences in color coordinates of dark substrates were recorded after the substrate was covered by an aluminum oxide disk and also after the addition of veneering porcelain to the aluminum oxide disks in group 1 (P=0. 000 2) and group 2(P=0. 007 5) and between 2 groups (P=0. 000 1). Conclusion -The ability of masking underlying discoloration was increased and shifted to gray when the thickness of veneering porcelain increased.
