Human skin is comprised of an element called collagen. Collagen is a protein which consists of fibroblasts, which are specialized cells. When scabs form on the skin, the fibroblasts which reside beneath the surface will start to drain into the clot which sits beneath the scab. When the clot is soaked with a sufficient number of fibroblasts they will begin secreting collagen, which will lead to a growth factor. This growth factor will then allow the fibroblasts to showcase their contractile proteins, which will transform them from migratory cells into cells which will close and firmly pull a wound together.
The different types of scars
Scars and normal skin share the same proteins. However, they appear different because of the protein composition. Rather than utilizing a “basket weave” structure, the proteins from scars will be stretched into alignment within a single direction. Additionally, scars are also devoid of sweat glands, sebaceous glands or hair follicles. As a result, scar texture tends to be smooth as well as itchy.
Scars come in different varieties. They are classified based on appearance and are a result of the presence of too much collagen, as well as the degranulation of some cell types. The three most common scars are atrophic, hypertrophic and stretch marks (which many people don’t realize are scars). Hypertrophic scars have an appearance that is raised, and which extends over an area that has been previously wounded.
Atrophic scars appear sunken in appearance. These types of scars are typically the result of acne, skin infections or chicken pocks. They may also appear in situations where fat tissue or muscle beneath the scar area has been damaged, potentially due to inflammation which results from an injury. The third type of scar, which is referred to as a stretch mark, is distinct in that it usually does not result from an injury or wound. Stretch marks appear when the skin is stretched faster than its capacity to handle.
When this occurs, mast cells will start to degranulate, and will release molecules that assist in the destruction of undesirable microorganisms. When degranulation occurs too much, this results in the appearance of stretch marks. Stretch marks commonly appear in pregnant women, teenagers and those that undergo certain types of surgery.
Additional Scarring Facts
Stretch marks are very common, and in the U.S. it is estimated that up to 90% of women will get them, as well as 70% of teenage females and 40% of teenage males. Wounds which are sustained to early embryos can heal perfectly with no scarring at all, or evidence of the wound. This ability is believed to be caused by the secretion of fibroblasts. Researchers who studied these embryos conducted tests on adults to determine if the same phenomenon could occur, and they discovered that the wounds in adults can also heal without scarring.
The regeneration of lost limbs is also related to scars. Many animals regenerate limbs which have been severed, and the mechanism for doing this is also similar to scarring, as the animals which regenerate their limbs also have scarring within the same tissue.
This article was not written by Dr. Robert S. Fischer M.D and may not represent his views. To talk to Dr. Robert S. Fischer M.D. please contact the office directly.
