128 results about "Dermal papillae" patented technology

In the human skin, the dermal papillae are small, nipple-like extensions of the dermis into the epidermis. At the surface of the skin in hands and feet, they appear as epidermal or papillary ridges. Blood vessels in the dermal papillae nourish all hair follicles and bring nutrients and oxygen to the lower layers of epidermal cells. The pattern of ridges they produce in hands and feet are partly genetically determined features that develop before birth. They remain substantially unaltered throughout life, and therefore determine the patterns of fingerprints, making them useful in certain functions of personal identification. The dermal papillae are part of the uppermost layer of the dermis, the papillary dermis, and the ridges they form greatly increase the surface area between the dermis and epidermis. Because the main function of the dermis is to support the epidermis, this greatly increases the exchange of oxygen, nutrients, and waste products between these two layers. Additionally, the increase in surface area prevents the dermal and epidermal layers from separating from each other by strengthening the junction between them.