Denforus Co, Seoul, Korea.
J Prosthet Dent. 2010 Sep;104(3):173-81. doi: 10.1016/S0022-3913(10)60116-3.
The color attributes of commercially available shade guides have been measured by spectrophotometers (SP), which are designed to measure flat surfaces. However, there is limited information on the color distribution of shade guides as measured by spectroradiometers (SR), which are capable of measuring the color of curved surfaces.
The purpose of this study was to determine the distributions of lightness (CIE L*) and chroma (C*(ab)) step intervals between adjacent shade tabs of a shade guide based on the lightness, chroma, and hue attributes measured by an SR.
Lightness, chroma, hue angle, and CIE a* and b* values of the shade tabs (n=26) from a shade guide (Vitapan 3D-Master) were measured by an SR under daylight conditions. The distributions of the ratios in lightness and chroma of each tab compared with the lowest lightness tab or the lowest chroma tab were determined. The values for each color parameter were analyzed by a 3-way ANOVA with the factors of lightness, chroma, and hue designations of the shade tabs (alpha=.05).
The chroma and CIE a* and b* values were influenced by the lightness, chroma, and hue designations of the shade tabs (P<.001); however, the lightness and hue angle were influenced by the lightness and hue designations, but not by the chroma designation. Distributions for the CIE a* and b* values, in each lightness group, corresponded with the chroma designation. However, the intervals in the lightness and chroma scales between adjacent tabs were not uniform.
The intervals in the color parameters between adjacent shade tabs were not uniform based on SR measurements. Therefore, a shade guide in which shade tabs are more equally spaced by the color attributes, based on the values as measured by an SR along with observers' responses with respect to the equality of the intervals, should be devised.
市售比色指南的颜色属性已通过分光光度计（SP）进行了测量，分光光度计旨在测量平面。然而，关于比色仪（SR）测量比色指南的颜色分布的信息有限，比色仪能够测量曲面的颜色。
本研究的目的是根据 SR 测量的明度、彩度和色调属性，确定比色指南中相邻比色片之间明度（CIE L*）和彩度（C*（ab））阶跃间隔的分布。
在日光条件下，使用 SR 测量比色指南（Vitapan 3D-Master）中比色片（n=26）的明度、彩度、色调角以及 CIE a和 b值。确定各比色片的明度和彩度与最低明度比色片或最低彩度比色片的比值分布。使用 3 因素方差分析（因素为比色片的明度、彩度和色调标注）分析各颜色参数值（alpha=.05）。
彩度和 CIE a和 b值受比色片的明度、彩度和色调标注的影响（P<.001）；然而，明度和色调角受明度和色调标注的影响，但不受彩度标注的影响。在每个明度组中，CIE a和 b值的分布与彩度标注相对应。然而，相邻比色片之间的明度和彩度标尺的间隔并不均匀。
基于 SR 测量，相邻比色片之间的颜色参数间隔不均匀。因此，应该设计一种比色指南，其中比色片根据 SR 测量值以及观察者对间隔均匀性的反应，通过颜色属性更均匀地间隔开。
