A scar is a fibrous tissue area that replaces normal skin after an injury. Scars result from the biological process of repairing wounds on the skin, as well as in other organs and tissues. Thus, scarring is a natural part of the healing process. With the exception of very small lesions, any injury (eg, after accident, disease, or surgery) results in multiple levels of scarring. Exceptions to this are animals with complete regeneration, which regrow tissue without scar formation.
The scar tissue consists of the same protein (collagen) as the tissue it replaces, but the protein fiber composition is different; instead of forming a random basket basket of collagen fibers found in normal tissue, in collagen fibrosis crosslinking and forming a real alignment in one direction. The alignment of this collagen scar is usually an inferior functional quality to the normal random smoothing of collagen. For example, skin scars are less resistant to ultraviolet radiation, and the sweat glands and hair follicles do not grow back in scar tissue. Myocardial infarction, commonly known as a heart attack, causes scar formation in the heart muscle, leading to loss of muscle strength and possibly heart failure. However, there are some tissues (eg bones) that can heal without structural or functional damage.
Video Scar
Type
All scar tissue is composed of the same collagen with the tissue that has been replaced, but the scar tissue composition, compared with normal tissue, is different. Scar tissue also does not have elasticity like normal tissue that distributes fiber elasticity. Scars differ in the amount of collagen overexpression. Labels have been applied to differences in overexpression. The two most common types are hypertrophic and keloid scarring, both of which undergo excessive rigid collagen growth through tissue, inhibiting tissue regeneration. Another form of scar tissue is atrophy (scar tissue), which also has overekspresi regeneration blocking collagen. This type of scar is concave, because the collagen bundle does not burden the network. Stretch mark (striae) is considered a scar by some people.
High levels of melanin and African or Asian descent can make more harmful scars more visible.
Hypertrophic
Hypertrophy scars occur when the body overproduces collagen, which causes the scar to be lifted over the surrounding skin. Hypertrophic scars take the form of a red bump on the skin. They usually occur within 4 to 8 weeks after wound infection or wound closure with excess tension and/or other traumatic skin injuries.
Keloid
Keloid scar is a more serious form of excessive scarring, because they can grow indefinitely into large, tumorous (although benign) neoplasms.
Hypertrophic scars are often distinguished from keloid scars due to a lack of growth beyond the original wound area, but the differences that are commonly taught can cause confusion.
Keloid marks can happen to anyone, but they are most common in dark-skinned people. They can be caused by surgery, accidents, acne or, occasionally, body piercings. In some people, the keloid scar is formed spontaneously. Although they can be a cosmetic problem, the keloid scar is just a mass of collagen iners and therefore completely harmless and not cancerous. However, they can be itchy or painful in some individuals. They tend to be most common on the shoulders and chest. Hypertrophic and keloid scars tend to be more common in wounds covered by secondary intentions. Surgical removal of keloids is risky and may aggravate the condition and worsen keloids.
Atrophy
Atrophic scars take the form of a concave recess in the skin, which has a pitted appearance. This is caused when the underlying structure of the skin support, such as fat or muscle, is lost. This type of scarring is often associated with acne, chicken pox, other diseases (especially Staphylococcus infections), surgery, insect bites and certain spiders, or accidents. This can also be caused by disruption of genetic connective tissue, such as Ehlers-Danlos syndrome.
Stretch mark
Stretch marks (technically called striae ) are also scars. This is caused when the skin stretches quickly (eg during pregnancy, significant weight gain, or adolescent growth), or when the skin is put under pressure during the healing process (usually near the joint). These scars usually improve after a few years.
Increased levels of corticosteroids are involved in the development of striae.
Umbilical
Humans and other placental mammals have umbilical scar (usually referred to as the navel) which begins to heal when the umbilical cord is cut after birth; In addition to placental mammals, laying animals have umbilical scars that usually disappear within a few days after birth or remain visible for life depending on the species.
Maps Scar
Pathophysiology
Scar is the product of the body repair mechanism after tissue injury. If the wound heals quickly within two weeks with the formation of new skin, minimal collagen will be stored and there will be no scars. Generally, if the wound takes longer than three to four weeks to cover, a scar will form. Small full thickness of wound under 2mm reepithilize quickly and heal free scar. Second-degree burns heal with scarring and hair loss. Sweat glands do not form in scar tissue, which interfere with the body temperature setting. Elastic fibers are generally undetectable on scar tissue younger than 3 months. In the post the scar disappears; through the lack of rete peg scars tend to be easier to cut than normal tissue.
Endometrium, the inner lining of the womb, is the only adult tissue undergoing surgery and rapid cyclic regeneration without scarring; shed and restore approximately within the 7-day window of the month. All other adult tissues, after rapid shedding or injury, can cause scars.
Prolonged inflammation, as well as fibroblast proliferation may occur. Redness that often occurs after injury to the skin is not a scar, and is generally not permanent (see wound healing). The time it takes for this redness to disappear may, however, range from a few days to, in some serious and rare cases, several years.
Scars are formed differently based on the location of injuries on the body and age of the injured.
The worse the initial damage, the worse the scars are.
Skin scarring occurs when the dermis (thick layer of deep skin) is damaged. Most of the skin scars are flat and leave the original scar causing them.
The lesions that are left healed tend to be more severe than the wounds from the primary closure.
Collagen synthesis
Any injury does not become scarred until the wound is completely healed; this can take months, or years, in the worst pathological cases, such as keloids. To start patching damage, blobs are created; A blood clot is a preliminary process that produces a temporary matrix. In the process, the first layer is a temporary matrix rather than a scar. Over time, the injured body tissue then overexpresses collagen within the temporary matrix to create a collagen matrix. This over expression of collagen continues and binds cross-regulating fibers within the collagen matrix, making the collagen denser. This solid collagen, transformed into an inelastic whitish collagen scar, prevents cell communication and regeneration; as a result, the resulting new network will have a different texture and quality than the surrounding boundless network. This prolonged process of collagen production produces fortuna scars.
Fibroblast
The scar tissue is made by the proliferation of fibroblasts, a process that begins with a reaction to a blood clot.
To repair the damage, fibroblasts slowly form a collagen scar. Proliferation of circular and cyclical fibroblasts, fibroblast proliferation places thick and whitish collagen in a temporary matrix and collagen, resulting in the production of abundant dense collagen in fibers that provide uneven texture. Over time, fibroblasts continue to crawl around the matrix, adjusting more fibers and, in the process, scar tissue settles and becomes stiff. The proliferation of fibroblasts also contracts the tissues. In non-moistened tissue, this fiber is not expressed with thick collagen and does not contract.
Myofibroblast
The fibroblasts involved in scarring and contraction are miofibroblasts, which are specialized contractile fibroblasts. These cells are expressing? - an actin muscle (? -SMA).
Myofibroblasts are absent in the first trimester at the stage of the embryo where the damage heals free grate; in an incision wound or small excision less than 2 mm which also heals without scarring; and on adult tissue not removed where fibroblasts are themselves captured; However, miofibroblasts are found in large quantities in the healing of adult wounds that heal with scars.
Myofibroblasts form a high proportion of fibroblasts that proliferate in postembryonic wounds early in healing. In mouse models, for example, myofibroblasts can form up to 70% of fibroblasts, and are responsible for fibrosis in the tissues. Generally, the miofibroblasts disappear from the wound within 30 days, but may remain in the pathological case of hypertrophy, such as keloids. Myofibroblasts have plasticity and in mice can be converted into fat cells, not scar tissue, through the regeneration of hair follicles.
Treatment
The initial and effective treatment of acne scarring can prevent severe acne and frequent scarring. In 2014 there is no prescription medication for the treatment or prevention of scars available.
Chemical peels
Chemical exfoliation is a chemical that destroys the epidermis in a controlled manner, leading to exfoliation and alleviation of certain skin conditions, including superficial acne scars. Various chemicals may be used depending on the depth of the skin, and caution should be used, especially for dark-skinned individuals and people who are susceptible to keloid formation or with active infection.
Injector filler
Filler collagen injections can be used to lift the atrophic scar to the surrounding skin level. Risks vary based on the filler used, and may include further damage and allergic reactions.
Laser Treatment
Non-viable lasers, such as 585nm pulsed laser, 1064 nm and 1320 Nm: YAG, or 1540 nm. Er: Glass is used as a laser therapy for hypertrophic and keloid scars. For scars they improve the appearance.
Ablative lasers such as carbon dioxide (CO 2 ) or Er: YAG offer the best results for atrophic and acne scars. Like dermabrasion, the ablative laser works by destroying the epidermis to a certain depth. The healing period for ablation therapy is much longer and the risk profile is greater than for nonlative therapy; However, nonlative therapy offers only minor improvements in cosmetic appearance of atrophic scars and acne.
Radiotherapy
Low-dose superficial radiotherapy is sometimes used to prevent severe keloid and hypertrophic scarring. It is considered effective despite the lack of clinical trials, but is only used in extreme cases because of the perceived risk of long-term side effects.
Dressing
Treatment of silicone scars is usually used to prevent scar formation and repair of existing scars. A meta study by Cochrane collaboration found weak evidence that the silicone gel coating helps prevent scarring. However, the study was poor quality and vulnerable to bias.
Pressure dressings are commonly used in managing burns and hypertrophics, although supporting evidence is lacking. Treatment providers generally report improvements, however, and pressure therapy has been effective in treating keloid of the ear. General acceptance of effective treatment can prevent it from being studied further in clinical trials.
Steroids
Long-term corticosteroid injections into the scar can help flatten and soften the appearance of a keloid or hypertrophic scar.
Topical steroids are not effective.
Surgery
Revision of the scar is the process of cutting out the scar tissue. After excision, new wounds are usually closed to heal with primary intentions, not secondary intentions. Deeper cuts require multiple layers of cover to heal optimally, otherwise they may cause a depressed scar or dent.
Excision of hypertrophic or keloid scar surgery is often associated with other methods, such as pressotherapy or silicone gel sheets. However, keloid scar excision, indicating a recurrence rate approaching 45%. A clinical study is currently underway to assess the benefits of treatment that combine surgery and healing with laser help on hypertrophic or keloid scars.
Subcision is a process used to treat deep scars left by acne or other skin diseases. It is also used to reduce the appearance of severe glabella lines, although its effectiveness in this application is debatable. Basically this process involves separating skin tissue in the affected area from deeper scar tissue. This allows the blood to stagnate under the affected area, eventually causing a deep scratching scar to equalize with the rest of the skin area. After the skin is flattened, treatments such as laser coating, microdermabrasion or chemical peeling can be used to smooth the scar tissue.
Vitamins
Research shows the use of vitamin E and onion extract (sold as Mederma) as a treatment for ineffective scars. Vitamin E causes contact dermatitis in up to 33% of users and in some cases may aggravate the appearance of scars and may cause mild skin irritation, but Vitamin C and some of its esters fade dark pigment associated with multiple scars.
More
- Cosmetics; Medical makeup can cover a temporary scar. This is most often used for facial scars.
- Dermabrasion involves removal of the skin surface with special equipment, and usually involves local anesthesia.
- Massage has evidence of weak efficacy in scar management. The beneficial effects seem to be greater in the wounds created by the surgical incision than the traumatic injury or burns.
- Microneedling
Society and culture
Intentional scarring
The immortality of scar tissue has led to deliberate use as a form of body art in some cultures and subcultures. These forms of ritual and non-ritual practice are found in many groups and cultures around the world.
Etymology
First proved in English at the end of the 14th century, the word scar is from the Old French escharre , from the Latin End eschara , which is the latinization of the Greeks ?????? ( eskhara ), meaning "fireplace, fireplace", but in "scabies, eschar on wounds caused by burning or other".
Research
Intradermal injection to change the growth factor of beta 3 (TGF 3) is being tested. Results from three completed experiments published in Lancet along with editorial comments.
A study involving the ribosomal s6 kinase (RSK) protein in scar tissue formation and finding the introduction of chemicals to combat SSR may stop cirrhosis formation. This treatment also has the potential to reduce or even prevent at all other types of scar tissue.
Research also involves osteopontin in scar tissue.
References
External links
- WebMd.com: Skin Scars Directory
- American Dermatology Academy: What is a scars?
Source of the article : Wikipedia
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