What structure covers the matrix area of the nail?

The structure that covers the matrix area of the nail is the cuticle. The cuticle, also known as the eponychium, forms a protective barrier at the base of the nail, where the new nail cells are generated in the matrix. This protective covering helps to prevent pathogens from entering and affecting the sensitive growing tissue underneath.

In contrast, the hyponychium is located beneath the free edge of the nail, providing a barrier from the underlying skin, while the nail bed is the area beneath the actual nail plate that supports it. The sidewall, also referred to as the lateral nail fold, is the outer edge of the nail that helps protect the sides of the nail plate. These structures each have unique functions but do not cover the matrix area, highlighting the specific role of the cuticle in nail health and growth.