The Influence Of Dentin Porcelain Layer Thickness On The Color Match Of Metal Ceramic Restorations

Background: Porcelain restorations have double-layer color effects resulting from the presence of translucent and opaque layers. Enough thickness of translucent dentin porcelain was needed to imitate the optical property of natural teeth. Purpose: this study was to investigate the influence of dentin layer thickness on the color match of two different metal ceramic systems.Material and methods: two metal ceramic systems (Vita VMK95, Shofu Vintage Halo) were evaluated each in shade A2, A3.5, B2, C1. Five specimens of each system of each shade were fabricated at the dentin thicknesses of 1.6, 1.2, 0.8, and 0.4mm. The CIEL*a*b* value of each specimen and standard shade guide tabs were measured by a dental Chroma meter. Color differences (AE) between specimens and shade tabs were calculated. Correlation between the dentin thickness and the AE ,L*, a*, and b* values was analyzed in Spss. Results: the Color differences between specimens and shade tabs vary from 2.97 to 12.61. High L* is the primary reason for the color difference in Vita metal ceramic, while High L* and b* play the same important role in color difference for Shofu metal ceramic. Compare to Vita metal ceramic. Shofu Vintage Halo is lighter and more saturated.Conclusion: the color match of metal ceramic is influenced by the dentin porcelain thickness, The color varies in different metal ceramic systems; the Color of Shofu Vintage Halo is less sensitive to the change of thickness of dentin. While the color match ability is also influenced by the target shade tab.