Scars and the Skin Repair Process

The elimination or fading of scars, lesions, and stretch marks from the skin depends on a process called "skin remodeling".

The skin is designed to heal wounds rapidly to avoid blood loss and infections. Scars are created from a quickly formed "collagen glue" that the body deposits into an damaged area for defense and strength. In ideal skin repairing, damaged skin is quickly closed, and then the healed area is slowly reconstructed to remove the residual collagen scars and blend the skin area into nearby skin.

Scar collagen is eliminated and replaced with a mixture of skin cells and invisible collagen fibers. This work may continue in a skin area for up to ten years.

In children, the remodeling speed is high and scars are usually rapidly eliminated from damaged skin areas. But as we reach adulthood, this rate slows down and small scars may stay there for years.

One way to accelerate repair is to provoke a little amount of controlled skin damage with a needle, laser, acid, or other means, and then let the body repair processes reconstruct the skin area.

An alternative procedure is to use enzymes and activators of skin renewal fibroblasts to increase the body's natural healing mechanisms and achieve even better final results. Fibroblasts are the cells in the basal membrane of the skin and they are the precursors of all the structural elements of healthy skin, including those that provide moisture, tensile strength and elasticity to skin. Enzymes dissolve or "digest" damaged and dying cells.

Wound Healing

Scars are always formed to reconnect skin that has been damaged. Initially, they may be red or dark and pink after the wound has healed but will become softer and flatter naturally over time, resulting in a flat, pale scar.

For reasons that are yet to be fully understood, some people suffer from raised scars that are red and thick and may be itchy or painful. Others develop scars that extend beyond the site of an injury, called keloid scars.

Keloid scars are actually thick, puckered, itchy scars that grow beyond the edges of a wound or incision and rarely regress. They appear when the body continues to produce tough, fibrous protein (known as collagen) after a wound has been repaired.

Keloids can result from any type of injury to the skin, including scratches, tattoos, injections, insect bites or medical procedures. Keloids can appear on any part of the body, but most commonly occur over the breastbone, on earlobes and on shoulders.

Keloids are fibrotic tumors characterized by a collection of atypical fibroblasts with excessive deposition of extracellular matrix components, especially collagen, fibronectin, elastin, and proteoglycans. Histologically, keloids contain relatively acellular centers and thick, abundant collagen bundles that form nodules in the deep dermal portion of the lesion. Keloids present a clinical problem that must be addressed as these lesions can cause great pain, pruritus (itch) and physical disfigurement, may not improve in appearance over time, and can even limit mobility if located over a joint.

Hypertrophic scars use to be hard to distinguish from keloid scars histologically and biochemically, but unlike keloids, hypertropic scars remain confined to the wounded site and use to mature and flatten out over time. Both types secrete larger quantities of collagen than normal scars, but typically the hypertrophic type shows declining collagen synthesis after about 24 weeks. Hypertrophic scars contain about twice as much glycosaminoglycans as normal scars, and this and enhanced synthetic and enzymatic reactions result in marked changes in the matrix which affects the mechanical properties of the scars, including decreased extensibility that makes them feel firm.

As with hypertrophic scarring, people who have developed one keloid scar are likely to be prone to this condition in the future and should alert their doctor or surgeon if they are going to need injections or to have any form of surgery.

Atrophic scars use to cause a thinning and diminished elasticity of the skin due to a loss of normal skin architecture. An example of an atrophic scar is striae distensae, also called stretch marks.