What is the Eponychium?

The eponychium is a fold of skin at the base of each nail that is designed to provide protection from bacteria and other microorganisms that might cause infection or inflammation. This structure is also sometimes referred to as the cuticle of the nail. In addition to being seen in organisms with nails like human beings, this structure can also be observed in animals with hooves and claws, serving a similar protective function.

The eponychium forms very early during the development of an embryo. It precedes the formation of the nails themselves, serving as a point of origin for the keratin-rich nail. As the nails form, the eponychium shrinks and changes shape, retreating to the base of the nail bed. It also folds over on itself, creating a wall that is designed to keep bacteria out of the upper layers of the skin that surround the nail.

The outermost edge of the eponychium is comprised of a layer of dead cells. They create a thin and transparent barrier that flakes off over time as new living cells push their way out onto the nail and eventually die as well. This is the section of the cuticle that is often lifted and trimmed during manicures. It is important to avoid the living section of the eponychium, as this can lead to infections as well as being very painful for the subject.

Like the rest of the epidermis, the eponychium is designed to renew itself very quickly. The skin must be quick healing because it incurs scores of small injuries every day. The upper layers of the skin include dead cells that are gradually shed as fresh cells work their way up towards the surface. This constant shedding and renewal is designed to ensure that the skin creates a complete and solid barrier to protect the inside of the body from hazards found in the outside world, ranging from ultraviolet radiation to fungi.

People may observe that the eponychium appears to peel and flake at times. This can occur for a variety of reasons, including changes in the skin, lack of moisture, and reactions to infections or inflammation. The hands are very vulnerable both to drying out and to infectious organisms and people can keep the skin and nails on the hands healthier by washing their hands regularly and drying them thoroughly afterwards, using moisturizers frequently, trimming the nails with care, and eating a balanced diet to ensure that sufficient nutrients are supplied.