Pierre J, Francois G, Benize A M, Rubert V, Coutet J, Flament F
L'Oréal Research and Innovation, Chevilly Larue, France.
Int J Cosmet Sci. 2018 Oct;40(5):482-487. doi: 10.1111/ics.12488.
To determine the homogeneity in the distribution of two cutaneous functions (hydration and elasticity) along the entire human face.
The half faces (right or left, randomly chosen) of two groups of Caucasian women were measured on 24 different small sites (elasticity) and 41 others (hydration), by instruments of small-sized probes (Cutometer and Corneometer , respectively). Hydration of the face was recorded at different times (up to 24 h), post application of a highly hydrating product. The recorded values (left and right half faces) were further gathered and digitally positioned on a virtual feminine face and their intensity was illustrated through a colored white (lower values)-blue (higher values) scale.
The reconstitution of the mapping of the two measured parameters (from the left and right sides of different subjects), shows a perfect symmetry vis à vis the nose axis. However, both parameters present slightly variable but significant values along the human face. Sites from the temple are less elastic than chin or forehead. The upper and lower parts of the forehead show slight disparities in their elasticity values. Cheeks are significantly less prone at retaining their imparted hydration status (lost 2 h after application of a hydrating product) as compared to sub-ocular regions or chin that retain their hydration up to 24 h. Attempts to establish a mutual relationship between the two skin properties unsurprisingly failed.
The two studied skin properties show a slight but highly symmetric disparity along the entire human face.
确定两种皮肤功能（水合作用和弹性）在整个人面部的分布均匀性。
分别使用小型探头仪器（Cutometer和Corneometer），对两组白种女性的半张脸（随机选择右侧或左侧）在24个不同的小部位（弹性）和另外41个部位（水合作用）进行测量。在涂抹高保湿产品后，于不同时间（最长24小时）记录面部的水合作用情况。将记录的值（左右半张脸）进一步汇总，并数字化定位在一张虚拟女性面部上，其强度通过白色（较低值）-蓝色（较高值）的彩色标度来显示。
对两个测量参数（来自不同受试者的左右两侧）的图谱重建显示，相对于鼻轴呈现出完美的对称性。然而，这两个参数在人脸上均呈现出略有变化但显著的值。太阳穴部位的弹性低于下巴或额头。额头的上部和下部在弹性值上存在轻微差异。与可保持水合作用长达24小时的眼周区域或下巴相比，脸颊保持所赋予的水合状态的能力明显较弱（在涂抹保湿产品2小时后就会丧失）。不出所料，试图建立这两种皮肤特性之间的相互关系的尝试失败了。
所研究的两种皮肤特性在整个人面部呈现出轻微但高度对称的差异。
