| Normally, core materils of all ceramic is white to ivory color, also relatively translucent, which makes it easier to mimic the natural teeth color, However, white framework are not desirable in every case, applying opaquer as metal ceramic will lose some translucence. If the zirconia structures were shaded to adapt the brightness and chroma of the tooth to be restored, harmony color match with neighboring teeth would be arrived simpler, tooth preparation would conserve more substance. In previous research, the technology of producing partially sintered porous alumina block had been solved. This study attempts to make a solution on how to match the color between glass infiltrating alumina core ceramic and the Vitadur Alpha veneering ceramic. The effects on the color of infiltrating alumina ceramic of different metal oxides were investigated. Based on these study, it was found that lightness of the core material is the most important factor, followed was chroma, and the least is hue. Then, four kinds of infiltration glass powder with specified color were developed successfully. The color of infiltration alumina ceramic were tested. The color match between alumina core ceramic and the Vitadur Alpha veneering ceramic were also tested. In this study, zirconium oxide was shaded by mixing metal oxides with 3Y-TZP powder, the purpose is to investigate the effects of different colorants and it's composites on the color of dental zirconia, to develop a series of intrinsic colored dental zirconia. Results show as follows:1. Uncolcred glass and colored glass powder with 4% ceric oxide and 0.5% ferric oxide were fabricated. Primary mixture powder were made by mixing the two colored glass powder with 0.1g interval, and then 81 kinds of colored mixture powder were gained by mixing uncolored powder with the primary mixture powder. Molten glass was infiltrated into presintered alumina blocks. The colored AGC and VITAPAN-3D-MASTER shade guide were measured with spectrophotometer. Experiment results showed that the Yxy value of VITAPAN-3D-MASTER shade guide distributed from (185,0.378,0.340) to (121,0.443,0.341) and the Yxy value of colored AGC distributed from (227,0.352,0.343) to (102,0.489,0.364). There were 37 kinds of samples in the color range of shade guide. The color range of 81 kinds of AGC covered that of the VITAPAN-3D-MASTER shade guide.2. The reflectance curve of core ceramic infiltrated by AG 1-AG 4 glass powder demonstrated the similar trend as that of the core ceramic infiltrated by Vita In-Ceram glass powder. All of the 4 color serials infiltrated core ceramic were veneered with Vitadur Alpha veneering ceramic, the color differences could be accepted clinically after veneered with 0.3mm opaque dentine and 0.4mm dentine ceramic.3. After shading by mixing metal oxides with 3Y-TZP powder, a series of intrinsic colored dental zirconia was developed with 5 graded lightness, the color space was L*: 67.76～77.78; a*:-2.19～3.80; b*:12.13～25.01, which was similar to Vita In-Ceram YZ coloring liquid shade guide, and accorded with the color space of people's nature teeth, it may be suitable for color matching with dental veneering porcelain.
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