Hawaii Nail Technology State Board Practice Exam

The matrix is the part of the nail responsible for determining its thickness and width. The matrix is situated under the cuticle and at the base of the nail beneath the proximal nail fold. It is composed of rapidly dividing cells that produce new nail cells, which harden and extend the nail as they grow out.

As the cells in the matrix multiply and mature, they contribute to the nail's overall structure. Specifically, the thickness and width are a direct result of how the matrix produces these cells. Variations in matrix activity can lead to differences in nail characteristics, including thickness and width.

To provide context about the other options, the nail bed acts as a support for the nail plate but does not produce nail cells itself. The proximal nail fold protects the matrix and does not contribute to the thickness or width of the nail. The epidermis is the outer layer of skin and is not directly involved in the formation of the nail plate itself.