What is the perionychium?

The perionychium refers specifically to the skin that overlaps the sides of the nail, forming a protective barrier around the nail structure. This definition aligns with the anatomical role of the perionychium, which helps secure the nail and contributes to the overall health and integrity of the surrounding area. The perionychium plays a vital part in shielding the nail from injury and infection, as well as maintaining its condition.

The other provided options describe different parts related to nails. The portion of living skin that supports the nail pertains more to the nail bed, while the fold of skin at the bottom refers to the cuticle area. Additionally, the protective layer over the matrix is distinct from the perionychium and focuses on the protection of the nail growth area located beneath the cuticle. Understanding these nuances of nail anatomy is essential for effective manicure and pedicure practices.