Division of Restorative, Prosthetic and Primary Care Dentistry, College of Dentistry, The Ohio State University, Columbus, Ohio 43210, USA.
J Prosthet Dent. 2012 Dec;108(6):362-9. doi: 10.1016/S0022-3913(12)60193-0.
The effect of different proportions of recast dental alloys on the color of overlying opaque porcelain (OP) is unknown.
The purpose of this study was to compare the color of OP applied on 2 different proportions (50% and 100%) of recast alloys with the color of commercially available shade tabs of OP.
Six different metal alloy systems (2 base: Metalloy CC, Cr-Co [B-MCC]; Heraenium NA, Ni-Cr [B-HNA]; 3 noble: Cerapall 2, Pd-Au [N-CP2]; Triumph, Pd-Ag [N-T]; V-Deltaloy, Au-Pd [N-VD]; and 1 high-noble: V-Gnathos Plus, Au-Pt [HN-GP]) were selected for the fabrication of disk-shaped specimens (10 mm in diameter, 1 mm in thickness). Each alloy was divided into 2 subgroups: 50% new alloy with 50% recast alloy (n=3) and 100% recast alloy (n=3). OP (B1) was applied (0.1 mm) to all specimens. The color coordinates (L*, a*, b*) of each specimen and the corresponding commercially available OP shade tab (control) were measured with a spectroradiometer, and color differences between specimens and control group were calculated. Data were statistically analyzed (2-way ANOVA, Ryan-Einot-Gabriel-Welsch multiple range test, α=.05).
For each alloy, ΔL*(L(control)(-)L(recastalloy)) values for the 2 subgroups were not statistically different from each other. The Δa* and Δb* of different proportions of N-CP2, B-HNA, N-VD, and HN-GP were not statistically different within the alloys. However, the a* values of 100% recast N-T and B-MCC were significantly closer to the a* values of the control group, and the b* values of 50% recast B-MCC were significantly closer to the b* values of the control group (P<.05). Delta E(control-recast) alloy values for different proportions of alloys were not statistically different. However, color differences did not meet the criterion of clinical acceptability (ΔE=3.46).
According to the results of this study, the different proportions (50% and 100%) of recast alloys used have similar effects on the color of OP. Differences between the final color of OP on the recast alloys used and the color of OP shade guide tabs did not meet the criterion of clinical acceptability considered in this study.
不同比例再铸造牙科合金对覆盖性不透明瓷（OP）颜色的影响尚不清楚。
本研究的目的是比较应用于 2 种不同比例（50%和 100%）再铸造合金的 OP 的颜色与市售 OP 比色片的颜色。
选择 6 种不同的金属合金系统（2 种基：Metalloy CC、Cr-Co [B-MCC]；Heraenium NA、Ni-Cr [B-HNA]；3 种贵金属：Cerapall 2、Pd-Au [N-CP2]；Triumph、Pd-Ag [N-T]；V-Deltaloy、Au-Pd [N-VD]；和 1 种高贵金属：V-Gnathos Plus、Au-Pt [HN-GP]）用于制作圆盘状试件（直径 10mm，厚度 1mm）。每个合金分为 2 个亚组：50%新合金与 50%再铸造合金（n=3）和 100%再铸造合金（n=3）。所有试件均应用 OP（B1）（0.1mm）。用分光光度计测量每个试件的颜色坐标（L*、a*、b*）和相应的市售 OP 比色片（对照），计算试件与对照组之间的颜色差异。数据采用统计学分析（2 因素方差分析、Ryan-Einot-Gabriel-Welsch 多重范围检验，α=.05）。
对于每种合金，2 个亚组的 ΔL*（L（对照）-L（再铸造合金））值彼此之间无统计学差异。不同比例的 N-CP2、B-HNA、N-VD 和 HN-GP 的 Δa和 Δb在合金内无统计学差异。然而，100%再铸造 N-T 和 B-MCC 的 a值与对照组的 a值更接近，50%再铸造 B-MCC 的 b值与对照组的 b值更接近（P<.05）。不同比例合金的ΔE（对照-再铸造）合金值无统计学差异。然而，颜色差异未达到本研究中考虑的临床可接受性标准（ΔE=3.46）。
根据本研究结果，使用的不同比例（50%和 100%）再铸造合金对 OP 颜色的影响相似。使用的再铸造合金上最终 OP 颜色与 OP 比色片之间的差异未达到本研究中考虑的临床可接受性标准。
