This multicenter study evaluated the effect of harmonizing spectrophotometric (d/8°) color measurements by using actual dental materials of clinically relevant thickness and translucency as “calibration tiles.” Ten tooth‐colored, 1‐mm thick, resin‐ and ceramic‐based materials were tested at the coordinating center (CC) and six research sites (RS). Correction factors were calculated for each material and each site to obtain the corrected reflection spectra from the non‐corrected data set. Non‐corrected (_NC) and corrected (_C) reflection values were converted into CIEDE2000 and CIELAB color parameters for the following comparisons: CC vs RS_NC and CC vs RS_C, between RS_NC vs RS_NC and RS_C vs RS_C pairs, and among RS separately (α = 0.05). Mean color differences for CC vs RS_NC and corresponding CC vs RS_C values were ΔE₀₀ = 4.2 (2.6) and ΔE₀₀ = 0.7 (0.6), respectively. Corresponding values for RS_NC vs RS_NC and RS_C vs RS_C specimen pairs were ΔE₀₀ = 5.9 (2.9) and ΔE₀₀ = 1.0 (0.5), respectively. The CIEDE2000 NC vs C comparison for each research site separately ranged from 0.5 to 8.5. Color differences of CC vs RS_C and RS_C vs RS_C pairs decreased 83% to 84.5% as compared with respective color differences for non‐corrected research site measurements and was RS dependent (P < .001). The obtained results validated the proposed method of harmonizing color measurements for dental application as a reliable quality control tool for dental research laboratories and industry.

中文翻译：

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牙科应用颜色测量的统一

这项多中心研究通过使用具有临床相关厚度和半透明性的实际牙科材料作为“校准砖”，评估了统一分光光度（d / 8°）颜色测量的效果。在协调中心（CC）和六个研究地点（RS）测试了十种牙齿色，厚度1毫米，树脂和陶瓷的材料。计算每种材料和每个部位的校正因子，以从未校正的数据集中获得校正的反射光谱。将未校正的（_NC）和校正的（_C）反射值转换为CIEDE2000和CIELAB颜色参数，以进行以下比较：CC vs RS _NC和CCvs RS _C，在RS _NC与RS _NC之间以及RS _C与RS _C对之间，以及在RS之间（α= 0.05）。对于平均色差CC VS RS _NC和对应CC VS RS _Ç值分别为ΔE ₀₀ = 4.2（2.6）和ΔE ₀₀分别= 0.7（0.6）。RS _NC与RS _NC以及RS _C与RS _C的对应值样本对分别为ΔE ₀₀ = 5.9（2.9）和ΔE ₀₀ = 1.0（0.5）。每个研究地点的CIEDE2000 NC与C的比较范围分别为0.5到8.5。的颜色差异CC VS RS _Ç和RS _Ç VS RS _Ç对下降83％至84.5％，而非校正研究现场测量各颜色的差异相比较，并为RS依赖性的（P <.001）。获得的结果验证了所提出的统一牙科应用颜色测量的方法，作为牙科研究实验室和行业的可靠质量控制工具。