The dermis layer of skin is beneath the epidermis, and its main function is temperature regulation and blood supply. The dermis also gives skin its thickness, and it makes up roughly 90 percent of the thickness of skin.
The dermis is comprised of many cells and structures. Blood and lymph vessels are contained within the dermis as well as hair follicles and sweat glands. The dermis is home to the sebaceous glands, which secrete oil to help skin keep its smooth texture. Nerve endings, collagen and elastin are also found in the dermis. The dermis has two sub-layers, including a papillary layer of thin collagen fibers and a reticular layer of thick collagen fibers.