Epidermis is directly exposed to various external stimuli and protects internal structures. Most studies about skin tension focused on the dermis, and epidermal tension has not been able to attract interest because dermis much thicker than epidermis and dermal collagen fibers play a predominant role in the skin tension. However, circumstances which involve only the epidermis are often shown, and thus it is necessary to study the mechanical property of the epidermis.

The purpose of this study is to quantify the role of the epidermis as a mechanical barrier.

Human epidermal sheets were obtained from suction blisters in 14 patients with vitiligo during epidermal grafting. Maximal tension, that is the power required to break the epidermal sheets, was measured by tensiometer.

The maximal tension of the epidermis ranged from 40.0 g/cm² to 84.5g/cm² with a mean values of 56.1g/cm² and did not differ significantly according to the age or anatomical sites.

The barrier function of epidermis is important and the results are expected to be used as the basic information for other studies about the mechanical property of the epidermis. In addition, this will be important data in developing an artificial skin whose mechanical property is similar to that of the human skin.