A scar is an area of fibrous tissue that replaces normal skin after an injury.
Scarring is the result of the biological process of wound repair and is a natural part of the healing process.
Scars occur after most wounds, including:
Cuts, insect bites and minor injuries
Minor scratches and bites only affect the outer layers of the skin but they can still leave a noticeable scar.
Deeper cuts and injuries can affect all layers of the skin. The healing process is more complex, likely to form a scab and take longer to heal. The resulting scar will be more noticeable than with minor injuries.
Acne mostly affects skin with the densest population of hair follicles; the face, the upper part of the chest, and the back.
Mild to moderate acne can result in a flat, red or brown mark that remains after a pimple has healed. These are not usually permanent scars but can take up to 6 months to fade.
More severe types of acne often cause the skin to suffer depressed or sunken areas due to deep tissue damage. Aside from scarring its main effects are psychological, such as reduced self-esteem.
The severity of a burn is determined by the depth of injury to the skin. Burn scars will often pull the edges of the skin together to create tight areas as they heal.
First degree burns damage the top layer of the skin only. It causes redness, pain and minor swelling.
Second degree burns damage the first two layers of skin. These burns cause redness, pain, blisters or an open wound and swelling.
Third degree burns are serious burns that extend to all the layers of the skin and may also damage deeper tissues.
Fourth degree burns extend beyond the skin to muscles, ligaments, nerves and even bones.
Surgery and more serious injuries
Because of the depth of incisions from surgery and serious injuries, scars will form. More modern surgical techniques such as laparoscopic surgery, also known as keyhole surgery, can minimise the size of the scar due to the small incisions required.