两种不同通透率Nacera氧化锆的色度学研究

Chromatographic Study of Two Nacera Zirconias with Different Transparency

目的:研究Nacera两种氧化锆的透明度和与Vita标准比色板A2色片的色差。方法:用CAD/CAM(computer aided design&manufacturing)将彩晶高透(Nacera Pearl)和彩晶低透(Nacera Shell)的氧化锆块加工成不同厚度(0.5、0.8、1.0、1.5mm)的圆盘形核心瓷块,然后在核心瓷上烧结厚度分别为1.0、0.7、0.5、0 mm的A2饰瓷(Noritake Kizai Co,Ltd,Nagoya,Japan),最后上釉。共制作40片直径为10.0mm、总厚度为1.5mm的氧化锆基底瓷片(n=5)。采用PR-655分光光度计测量试件在标准黑白板及4.0mm厚Dentin色树脂背景下的色度值,用来计算试件的相对透明度(translucency parameters,TP)值和与Vita Lumin Vacuum比色板A2色片的色差(△E)。结果:Nacera Shell组的TP值明显小于Nacera Pearl组。Nacera Pearl组随着核心瓷厚度增大,试件颜色与A2色片的色差变大,而Nacera Shell组的色差变化相对较小。结论:Nacera品牌的两种氧化锆均能较好地模拟比色板A2色片的颜色,但并非透明度越高的氧化锆最终修复颜色越好。

Objective： To study the transparency of two Nacera zirconia systems and their color difference with A2 color of Vita classical shade guide. Methods： The Nacera Pearl and Nacera Shell zirconia blocks were processed by CAD/CAM systems into disc-shaped core porcelain with different thicknesses （0.5mm, 0.8mm, 1.0mm, 1.5mm）, then veneered correspondingly with 1.0 mm, 0.7 mm, 0.5 mm, 0.0 mm thick veneer porcelain（Noritake Kizai Co., Nagoya, Japan） of A2 color and glazed. A total of 40 copings of φ10.0 mm, 1.5mm thick zirconia-based ceramic specimens were produced for this study （n=5）. PR-655 spectrophotometer was used to measure the color parameters of the specimens against standard black and white plates and 4.0mm thick dentin color resin. Then the relative transparency （TP） and the color difference （ΔE） with A2 color （Vita Lumin Vacuum shade guide） were calculated. Results： TP values of Nacera Shell were significantly smaller than Nacera Pearl. As the core thickness of the Nacera Pearl core increases, ΔE values between specimens and A2 color film became larger, and the color of Nacera Shell changed relatively small. Conclusion： Both systems of Nacera zirconia simulate the A2 color well. However, compared to high transparent zirconia, the color of low transparent zirconia is more stable.