VINTAGE A色系不同色号体瓷粉混色规律的研究

Research on the chromaticity change with the blending of different body shades of VINTAGE A dental porcelain in different ratios

目的探讨VINTAGE系列A色系不同色号体瓷粉按比例混合烧结后色度变化规律。方法将VIN-TAGE系列A1和A2、A1和A3、A2和A3、A3和A3.5体瓷粉分别按质量比9∶1、8∶2、7∶3、6∶4、5∶5均匀混合作为实验组,取单一色号A1、A2、A3、A3.5体瓷粉相同质量作为对照组,充填入石膏阴模,标准烧结程序进行1次烧结,样品瓷片进行表面打磨,并统一厚度为2mm。PR-650分光光度仪分别进行色度学测试,记录L*、a*、b*、C、H、ΔE值,进行参数分析。结果各组间L*值存在显著差异,但组内不同比例间L*值差异无统计学意义,a*、b*、C、H值在各混色组间和组内不同比例间差异均有统计学意义。随着色号数字增大,a*-b*色度点偏离线性,呈不规则非线性分布。混色组内相邻比例试样间色差值围绕1.5上下波动。结论减小瓷粉色号可以得到明度较高的修复体,仅单纯提高混合瓷粉中低色号瓷粉的比例,其效果不明显。随A色系瓷粉色号的增加,颜色逐渐从黄色向红色过渡。L*值对色差的影响最明显,L*值较小范围的波动会引起视觉可辨的颜色差异。对烤瓷材料基本成分和分子构架的研究,将有助于更深一步揭示瓷粉呈色规律和原理。

Objective This study was to explore chromaticity trend by mixing four body shades of VINTAGE A dental porcelain in different ratios under standard firing program. Methods Four body shades were arranged as A1 and A2,A1 and A3,A2 and A3,A3 and A3.5 in sample groups,and A1,A2,A3 and A3.5 in control group. Each sample group was mixed according to the quality proportion of 9∶1,8∶2,7∶3,6∶4 and 5∶5 respectively,and filled into plaster molds. These samples were fired following the manufacturers＇instruction,and the thickness was controlled by grinding to 2 mm. The chromatic analysis of these samples was taken through PR-650 spectrum detector. Then recorded the L＊,a＊,b＊,C,H,ΔE value,and calculated datas. Results There was no statistical difference on L＊ value in each group regardless of quality proportion. Significant difference could be found on L＊ value among groups,and on a＊,b＊,C,H value in and among each groups. The higher number of VINTAGE A body shades in the samples,the more deviation of a＊-b＊ coordinate points from linearity. Color differences between neighboring proportions in each group fluctuated around 1.5. Conclusion In the four different groups,the low number body shades resulted in high brightness changes. But within each group,high ratio of the lower number body shade affected little to the brightness. As the number increased,the color turned gradually from yellow to red. L＊ value made a greater contribution to the chromatic difference than other color parameters that a smallscale fluctuation of L＊ value may result in visible color changes. In addition,researches on the elementary components and molecule structure of dental porcelain will contribute to further study of the principle of dental porcelain color presence.