A scar is a permanent patch of skin that grows over a wound. It forms when your body heals itself after a cut, scrape, burn, or sore. You can also get scars from surgery that cuts through the skin, infections like chickenpox, or skin conditions like acne. Scars are often thicker, as well as pinker, redder, or shinier, than the rest of your skin.

How your scar looks depends on

• How big and deep your wound is
• Where it is
• How long it takes to heal
• Your age
• Your inherited tendency to scar

Scars usually fade over time but never go away completely. If the way a scar looks bothers you, various treatments might minimize it. These include surgical revision, dermabrasion, laser treatments, injections, chemical peels, and creams.

A sharply elevated, irregularly shaped, progressively enlarging scar resulting from formation of excessive amounts of collagen in the dermis during connective tissue repair. It is differentiated from a hypertrophic scar (CICATRIX, HYPERTROPHIC) in that the former does not spread to surrounding tissues.

Most cuts or wounds, with the exception of ones that only scratch the surface (the epidermis), lead to scar formation. A scar is collagen-rich skin formed after the process of wound healing that differs from normal skin. Scarring occurs in cases in which there is repair of skin damage, but the skin fails to regenerate the original skin structure. Fibroblasts generate scar tissue in the form of collagen, and the bulk of repair is due to the basket-weave pattern generated by collagen fibers and does not result in regeneration of the typical cellular structure of skin. Instead, the tissue is fibrous in nature and does not allow for the regeneration of accessory structures, such as hair follicles, sweat glands, or sebaceous glands.

Sometimes, there is an overproduction of scar tissue, because the process of collagen formation does not stop when the wound is healed; this results in the formation of a raised or hypertrophic scar called a keloid. In contrast, scars that result from acne and chickenpox have a sunken appearance and are called atrophic scars.

Scarring of skin after wound healing is a natural process and does not need to be treated further. Application of mineral oil and lotions may reduce the formation of scar tissue. However, modern cosmetic procedures, such as dermabrasion, laser treatments, and filler injections have been invented as remedies for severe scarring. All of these procedures try to reorganize the structure of the epidermis and underlying collagen tissue to make it look more natural.

How can I help prevent acne and acne scars?

You can help prevent acne flare-ups and scars by taking good care of your skin:

• Clean your skin gently with a mild soap or cleanser twice a day — once in the morning and once at night. You should also gently clean the skin after heavy exercise. Avoid strong soaps and rough scrub pads. Harsh scrubbing of the skin may make acne worse. Wash your entire face from under the jaw to the hairline and rinse thoroughly. Remove make-up gently with a mild soap and water. Ask your doctor before using an astringent.
• Wash your hair on a regular basis. If your hair is oily, you may want to wash it more often.
• Do not squeeze or pick at acne lesions. This can cause acne scars.
• Avoid getting sunburned. Many medicines used to treat acne can make you more prone to sunburn. Many people think that the sun helps acne, because the redness from sunburn may make acne lesions less visible. But, too much sun can also increase your risk of skin cancer and early aging of the skin. When you're going to be outside, use sunscreen of at least SPF 15. Also, try to stay in the shade as much as you can.
• Choose make-up and hair care products that are "non-comedogenic" or "non-acnegenic." These products have been made in a way that they don't cause acne. You may also want to use products that are oil-free.
• Avoid things that rub the skin as much as you can, such as backpacks and sports equipment.
• Talk with your doctor about what treatment methods can help your acne. Take your medicines as prescribed. Be sure to tell your doctor if you think medicines you take for other health problems make your acne worse.

When is surgery used for acne scarring?

If you have scarring, your dermatologist may suggest surgery to help heal acne lesions and remove scarring. A laser can reshape scar tissue and reduce redness. Dermabrasion is a type of surgery that can remove surface scars and reduce the depth of deep scars. Another option is to transfer fat from one part of the body to the face. In some cases, a single treatment can help scarring. But for lasting results, several are often needed. There are also topical treatments for acne scarring.

Photodynamic therapy is a new acne treatment. It begins with light microdermabrasion. This is used to remove dead skin cells on the face's surface. Then, an acid is put on the skin for 30 to 60 minutes. After this period, the acid is taken off. Lastly, the skin is treated with a laser. This treatment is still being researched, but seems to give positive long-term results.