Epidermal turnover time.

Epidermal turnover time is the time taken for the epidermis to replace itself. The turnover time can be subdivided; when the epidermis is divided into proliferative compartment, differentiated compartment, and stratum corneum, the total turnover time is the sum of the turnover time of each compartment. Using Weinstein's data (J Invest Dermatol 82: 623-628, 1984), the epidermal turnover time was calculated to be 47-48 days instead of 39 days.