* Nail Matrix: This is the active tissue located at the base of the nail, underneath the cuticle. The cells in the nail matrix divide and create new cells. As these new cells are produced, they push older cells forward.
* Keratinization: As the nail cells are pushed forward, they become flattened, hardened, and filled with keratin (a tough protein). These cells essentially die in this process, forming the hard nail plate we see.
* Nail Plate: This is the visible part of the nail. It's made up of dead, keratinized cells. It's not alive and doesn't have nerves or blood supply.
* Nail Follicle: The follicle is the structure surrounding the matrix and root of the nail. It provides support and helps guide the growth of the nail plate. The follicle *contains* the living matrix.
So, it's the living cells in the nail matrix that produce the new nail cells. These cells die and become the nail plate. The nail plate itself, once formed, is dead tissue and doesn't grow on its own. If the nail matrix is damaged and stops producing new cells, nail growth will cease. The term "dead nail follicle" is technically not accurate, as the follicle houses the living matrix. If the matrix dies, then nail growth stops.
To summarize:
1. The nail matrix (living tissue) produces new nail cells.
2. These cells become keratinized and die, forming the nail plate.
3. The nail plate (dead tissue) is pushed forward by new cells growing behind it.
4. The nail follicle supports the matrix and guides nail growth. A dead matrix stops nail growth, and the term "dead nail follicle" usually refers to this situation where the matrix is no longer functioning.