Color Evaluation Of Cerinate Porcelain Veneer Restorations

With the improving of living standards, patients have more demands on aesthetics of dental restorations. Porcelain laminate veneer restorations (PLV) have many strongpoints such as excellent aesthetics, color stability, and longevity etc. As a result, this kind of restorations have been popularized among today's dental practitioners for conservative restoration of unaesthetic anterior teeth.Harmonious shade match to the remaining dentition, particularly in the anterior region, is of primary importance to the success of PLV prosthesis. The factors that affect PLV restorations's color include PLV's shade, PLV's spectral transmittance, thickness of PLV, the color of tooth and cement. The effect of different factors were researched in the study with Cerinate PLV restorations. The potential of the color of natural tooth to be recovered with Cennate PLV was also evaluated. The study consisted of three parts. Part I : In different Vita shade and prepared in different thickness, the L*a*b* volumes of teeth and Cerinate porcelain veneers's were measured with Minota CR—321 Colorimeter. Part II: The spectral transmittance of Cerinate porcelain veneers and human teech enamel weremeasured with V570 spectrophotometer and compared each other. Part III: Colorimeter was used to measure the L*a*b* of the teeth surface without preparation and after covering with Cerinate Porcelain Veneers, and calculate their AE. According to the study, these conclusions can be drawn:a. From Vita shade A1 to A3, Lightness of Cerinate porcelain veneers declined, and Chroma mounted up, especially the value of b*. This is consistent to Vita standard Shade Guide.b. With the background of standard white plate, when the thickness of PLV increased, the value of L* dropped, but a*, especially b* increased. This implied Cerinate porcelain veneers's opaque capacity became strong when it was thicker.c.With the increase of preparation deepness, the value of L* decreased, a* changed a little, and the value of b* raised a lot.d. The spectral transmittance of Cerinate porcelain veneers didn't have difference when the thickness was the same but the color was different (P>0.05) .When the color was same, the spectral transmittance varied obviously as the thickness changed(P<0.01). These illuminated that the key factor to spectral transmittance of porcelain veneer is veneer's thickness, the color has little influence on it.e. The transmittance of Cerinate porcelain veneer and enamel in the same color and same thickness (1.00mm,0.75mm) didn't have significant difference (P>0.05) . But it's bigger for enamel than that of PLV when the thickness was 0.50mm (0.01