RESUMO
BACKGROUND:VITA 3D Master shade guide is a newly launched colorimetric system in recent years, with a wide clinical prospect. OBJECTIVE:To evaluate the significance of dentin colorimetric evaluation for accurate color section of cast ceramic prostheses. METHODS:Using conventional colorimetric assay and conventional colorimetric assay combined with dentin colorimetric assay (combined colorimetric assay), 30 patients were subject to colorimetric evaluation 1/3 to the neck, central part, and cut end of the tooth. In CIE1976L*a*b*color system, a digital SLR camera (Canon D50) was used for colorimetric measurement and analysis of cast ceramic prostheses prepared with two colorimetric methods and teeth with the same name. And a variety of new colorimetric methods were analyzed based on examples. RESULTS AND CONCLUSION:In the conventional colorimetric group,△L*was 1.22±0.16,△C*was 1.19±0.20,△H*was 0.31±0.05,△E*was 1.32±0.13. in the combined colorimetric group,△L*was 1.03±0.11,△C*was 1.12±0.19,△H*was 0.29±0.03,△E*was 1.23±0.11. Cast ceramic prostheses prepared by conventional colorimetric method were satisfactory in 22 cases, while cast ceramic prostheses prepared by the combined colorimetric method were satisfactory in 23 cases. There was no difference in patient satisfaction for color rendition (P>0.05), but chromatic difference analysis was significantly different between the two groups (P<0.05).