Scanning electron microscopic structure of the finger print as related to the dermal surface.

This paper aims to clarify the relationship of the dermis to epidermal ridge configuration. After fixation, human fingertip epidermis was peeled off from the dermis by alkaline treatment, and the dermal surface was observed with the scanning electron microscope (SEM). The SEM pattern of furrows, grooves, and papillae showed an exact negative fingerprint image. Papillae had various sizes and complicated shapes and were arranged continuously but irregularly on each side of the furrow. Size and shape variabilities were not dependent on the site of the fingerprint region. The papilla number tended to increase with age due to derivation of secondary papillae from the primary papilla as well as new formation of small papillae. The dermal surface exhibited some site-specific fibrous appearance at the furrow and papilla, whereas the surface was smooth at the groove. The characteristics of the dermal surface structure as related to the epidermis can be explained by a stronger dermis-epidermis adhesion at the furrow than at the papilla or at the groove.