Department of Oral and Maxillofacial Surgery, University Medical Center Groningen, Groningen, The Netherlands.
Int J Prosthodont. 2009 Nov-Dec;22(6):623-9.
A facial prosthesis demands a good visual match with the adjacent skin. Skin color and translucency must be mimicked by the prosthesis. Translucency can be defined as allowing the passage of light, yet diffusing it so as not to render the bodies beyond clearly visible, therefore being semi-transparent. The translucency of skin hampers color measurements of color meters recommended by the Commission Internationale de l'Eclairage (CIE) due to edge loss. The aim of this study was to analyze the translucency of skin at different body sites by measuring volume reflection in a cohort of Caucasian individuals.
To analyze skin translucency, a volume reflection meter (VRM) was applied to the skin of the forehead, cheek, palm of the hand, and lower forearm. The VRM measures the volume reflection of a small incident light beam at three different distances from the incident beam. To describe the impact of translucency on skin color and the impact of volume reflection at different distances of an incident beam, the VRM spectra were converted into CIE Lab* coordinates.
VRM measurements were carried out on a cohort of 48 individuals during spring. The mean age was 40.8 years (+/- 11.7 years). Statistically significant interactions between body site, distance from the light source, and L*, a*, and b* values were found. L* values decreased and a* and b* values increased at longer distances from the incident light beam since the light path was increased.
Skin on the forehead, cheek, palm of the hand, and lower forearm each have their own specific volume reflection and thus, translucency, absorption, and scattering characteristics. These location-specific characteristics are due to known local differences in the skin's multilayered structure. For a good visual match between a facial prosthesis and the adjacent skin, volume reflection measurements of the skin close to the intended site of the prosthesis are necessary.
面部赝复体需要与相邻皮肤具有良好的视觉匹配。赝复体的颜色和半透明度必须模仿皮肤。半透明度可以定义为允许光线通过，但又能使其扩散，从而使光线无法清晰地透出身体，因此呈现半透明状态。由于边缘损失，皮肤的半透明度会妨碍国际照明委员会（CIE）推荐的比色计对颜色的测量。本研究的目的是通过测量白种人群体不同身体部位的体积反射率来分析皮肤的半透明度。
为了分析皮肤的半透明度，我们将体积反射计（VRM）应用于前额、脸颊、手掌和小臂的皮肤。VRM 测量一小束入射光在与入射光束的三个不同距离处的体积反射率。为了描述半透明度对皮肤颜色的影响以及入射光束不同距离处的体积反射率的影响，将 VRM 光谱转换为 CIE Lab*坐标。
在春季，我们对一个由 48 人组成的队列进行了 VRM 测量。平均年龄为 40.8 岁（+/- 11.7 岁）。我们发现身体部位、光源距离和 L*、a和 b值之间存在显著的相互作用。随着与入射光束的距离增加，光程增加，因此 L值降低，a和 b*值增加。
前额、脸颊、手掌和小臂的皮肤各自具有特定的体积反射率，因此具有不同的半透明度、吸收和散射特性。这些位置特异性特征归因于皮肤多层结构的已知局部差异。为了使面部赝复体与相邻皮肤具有良好的视觉匹配，需要对靠近拟安装赝复体部位的皮肤进行体积反射率测量。
