In medical jargon, a scar is a fiber-rich replacement tissue of active fibroblasts (connective tissue cells), it is formed during wound healing. This process is called scarring. A scar is thus the final stage of the wound healing process.

Slight abrasions or other superficial injuries usually heal without any traces from itself. Larger wounds in which the damage extend below the dermis, the healing process pulls a scar by itself, in most cases.

Scars are often perceived as unaesthetic and disturbing for the person concerned. Also, because a scar is less elastic and less resilient than healthy skin.

The extent of scarring depends on the type of wound. Clean, sutured wounds are usually barely visible, whereas unclean, crushed or burned wound edges heal not as good.