Permanent damage to which structure may prevent nail regrowth after trauma?

• A. Matrix
• B. Nail bed
• C. Lunula
• D. Eponychium

Answer: (A)

The nail grows from the nail matrix, the tissue at the base that continuously produces the keratinized nail plate. If the matrix is permanently damaged, its ability to generate new nail material is lost, so the nail cannot regrow. The nail bed merely supports and nourishes the growing nail, so injury there can cause surface changes but doesn’t stop regrowth if the matrix remains intact. The lunula is simply the visible part of the matrix, not a separate regrowth source, and the eponychium (the cuticle) protects the matrix but isn’t responsible for nail production.