Characterization of the mechanical properties of skin by inverse analysis combined with an extensometry test

The human skin is a material that exhibits complex behaviors. However, the determination of its mechanical characteristics is a paramount goal for dermatology (pathologies), and for the cosmetics industry (skin ageing). In this study, we propose a new method for the determination of mechanical characteristics of human skin in vivo. This identification is based on experimental results that are obtained with the extensometry test. Its principle is to carry out a tensile test using two devices pasted to the skin. Then, experimental results are compared to those extracted from finite element models of this test. This comparison is made through an inverse method that uses a scheme of Extended Kalman filters. It enables to determine representative elastic mechanical parameters of this tissue. We introduce here experimental devices, the inverse method that we developed, and different analyses of phenomena that are related to cutaneous tissues stressed in that way. (C) 2007 Elsevier B.V. All rights reserved.