Effect of ceramic materials on the optical properties of porcelain veneers for tetracycline-stained teeth.

Objectives: To analyze the chromatic properties and translucency of porcelain veneers made from different ceramic materials against the background of tetracycline-stained teeth.

Methods: Porcelain specimens (A1, A3, B2, B4) measuring 0.50 mm in thickness were prepared by heat-press casting and layering. The L*, a*, and b* values of the specimens against simulated tetracycline tooth and black-and-white backgrounds were measured by a spectrophotometer, and color differences ΔE₀₀1 between specimens on simulated tetracycline backgrounds and the backgrounds themselves and ΔE₀₀2 between specimens on simulated tetracycline backgrounds and the white background were calculated. The translucent parameter (TP) was also evaluated.

Results: The ΔE₀₀1 of feldspathic specimens (IPS d.SIGN) with the opaque layer was significantly greater than that of glass ceramic specimens (IPS e.max Press LT), and the ΔE₀₀1 of group B4 was consistently greater than those of the other color groups (P<0.05). The ΔE₀₀2 values of all feldspathic specimens with the opaque layer were less than 1.25, and the ΔE₀₀2 values of the glass ceramic specimens were greater than 2.23. However, no significant difference was observed among the different color groups (P>0.05). The TP values of feldspathic specimens with the opaque layer were significantly lower than those of glass ceramic specimens(P<0.05), but no significant difference was observed among different color groups (P>0.05).

Conclusions: When changing the color of tetracycline-stained teeth, 0.50 mm-thick IPS d.SIGN feldspathic veneers with an opaque layer provide better chromatic properties than IPS e.max Press LT glass ceramic veneers. However, the translucency of feldspathic veneers is generally poorer than that of glass ceramic veneers.