Dermal Papilla: Structure and Function

The color of the skin is determined by the amount of melanin, a dark pigment, present in the epidermis, the outer layer of the skin. Higher concentration of melanin leads to darker skin.

Our skin that acts like a protective barrier against outside environment is primarily made up 3 different layers. While the topmost layer of the skin is the epidermis, the middle layer is the dermis, and the bottom-most layer is the hypodermics. Dermal papillae (singular: papilla) that will be discussed in the following Bodytomy article, lie at the dermo-epidermal junction, the zone that attaches the dermis layer to the epidermis.

Dermal papillae (DP) refer to the small extensions, protruding from the dermis layer of the skin. These nipple-like elevations indent the epidermis layer. They emerge from the papillary layer, which is the uppermost layer of the dermis, hence the name. The dermal papillae formed, substantially increase the surface area of the dermis layer.

Since dermal papillae lie in the dermo-epidermal junction, one of their functions is to keep the dermis and the epidermis layer well-connected. In simple words, dermal papillae help in strengthening the dermal-epidermal connectivity. This is extremely important since the epidermis has to depend on the dermis for blood circulation.

The epidermis does not contain any blood vessels. The blood supply comes from dermal papillae that contain capillaries. So one can say that the epidermis gets its nourishment from the dermal papillae. Simply put, the flow of nutrients to the epidermis is possible due to the presence of these underlying projections.

The dermal papillae also house the nerve endings that are also connected to the epidermis. These nerve endings can easily detect sense of touch, pressure as well as temperature variations that the epidermis is subjected to on a daily basis.

This sensory information is eventually conveyed to the brain. This is how the nerve endings that are located in the dermal papillae make us responsive to mechanical stimuli.

Dermal papillae also nourish the hair follicles, tiny sacs from where hair strands emerge and extend above the surface of the skin. They lie below the hair follicles and provide nutrition, which promotes hair growth.

Fingerprints that are unique to each person are also due to the presence of dermal papillae that are more noticeable in the fingertips, palms, and soles of the feet. As aforementioned, the dermal papillae extends upwards and strike the epidermis to form ridges (raised portion of the epidermis).

These epidermis ridges present on the hand create a unique fingerprint pattern that is classified in 3 main types: arch, loop, and whorl. For instance, the arch fingerprint is a wave-like pattern formed by the ridges. Also referred to dermal ridges, they form a unique pattern on every individual, which helps in identification during crime investigation.

On the whole, dermal papillae, the superficial extensions emerging from the dermis, play a crucial role in maintaining the epidermis layer. No wonder, it is often said that healthy functioning of dermal papillae is important to reap anti-aging benefits.