Translucency parameters of different CAD/CAM ceramics for monolithic restorations

Abstract

The translucency of dental ceramics [feldspathic ceramic (FC), lithium disilicate glass-ceramic (LD), zirconia-reinforced lithium silicate glass-ceramic (LS), and translucent zirconia (TZ)], in two thicknesses (1 and 2 mm), using different parameters was assessed. Translucency parameters (${\mathrm{TP}}_{\mathrm{ab}}^{*}$, TP₀₀), contrast ratio (CR), light transmittance at 468 nm (T%), and light attenuation were determined. Data were analyzed by ANOVA, Tukey’s test, and Pearson correlations (α=0.05). CR ranged from 0.64 (LS-1 mm) to 0.96 (TZ-2 mm). ${\mathrm{TP}}_{\mathrm{ab}}^{*}$ ranged from 3.7 (TZ-2 mm) to 32.2 (LS-1 mm). TP₀₀ ranged from 3.0 (TZ-2 mm) to 26.4 (LS-1 mm). T% ranged from 14.9 (TZ-2 mm) to 75.2 (FC-1 mm). Light attenuation varied from 54% (LS-1 mm) to 84% (TZ-2 mm). There were significant strong negative correlations between CR and ${\mathrm{TP}}_{\mathrm{ab}}^{*}$ (R=-0.997), CR and TP₀₀ (R=-0.991), ${\mathrm{TP}}_{\mathrm{ab}}^{*}$ and light attenuation (R=-0.888), and TP₀₀ and light attenuation (R=-0.867). LS showed the highest translucency, whereas TZ showed the lowest translucency. When thickness increased, CR and light attenuation also increased, while TP and transmittance decreased.

Keywords:
dental ceramics; translucency; light attenuation