Vita AB色系体瓷粉混合的色度变化趋势

The trend of chromaticity change with the blending of Vita A and B dentine porcelain powder

目的 考察按不同比例的VitaA2 ,B2 体瓷粉混合后色度变化趋势。方法 常规Ni-Cr合金片表面堆塑A2 遮色瓷及不同重量比例的A2 ,B2 混合体瓷粉 ,标准程序烧结 ,控制厚度 :遮色瓷 0 .3mm ,体瓷 1.0mm ,直径12 .0mm。白度色度计检测试件的色度参数 ,采用CIE1976L a b 表色系统 ,求取各组样本彩度值C ab及色相角H0 ab。结果 各组L 及b 值统计学上均无差异 ( P >0 .0 5 ) ;随A2 瓷粉重量比下降 ,B2 重量比增加 ,a 值逐渐下降 ,统计学上有显著差异 (P <0 .0 1)。结论 相同明度等级的VitaA2 、B2 瓷粉混合烧结后 ,其明度值 (L )基本保持不变 ;VitaA2 、B2 色系瓷粉混合后 ,其彩度 (C ab)向两瓷粉彩度区间移行 ,其色调 (H0 ab)

Objective To investigate the trend of chromaticity change through blending Vita A 2 and B 2 porcelain powder of different ratio and to supply theoretic basis for the shade blending in clinic.Methods Fired A 2 opaque porcelain and blended A 2 and B 2 dentine porcelain of different ratio on the Ni-Cr alloy disks was used under standard firing program to form a sample of 12.0mm diameter with 0.3mm thick opaque porcelain and 1.0mm thick dentine porcelain.CIE1976 L *a *b * color system was performed to record the chromaticity parameters of the samples.The C *ab and H 0ab of the samples of each groups was calculated.Results There was no statistical difference among each groups on L * value and b * value(P> 0.05 ).With the content of A 2 porcelain powder decreasing and the content of B 2 porcelain powder increasing,a * value decreased gradually (P< 0.01 ).Conclusion After blending and firing Vita A 2 and B 2 porcelain powder of the same brightness,L * was still unchanged,and the C *ab changed to the chroma space between the two types porcelain powder.With the increasement of the content of the respective porcelain powder,the Hue (H 0ab) can gradually change to it.