Geometrical models of the renewal of the epidermis

We give a review of the different models developed recently that describe t he renewal of the epidermis. These models, based on concepts borrowed from statistical mechanics, geometry and topology, shed new light on the underst anding of the organization and the dynamics of the system. We discuss in de tail a topological model of the dynamics of the inner-most layer of the epi dermis: the basal layer. (C) 2000 Academie des sciences/Editions scientifiq ues et medicales Elsevier SAS.