It is caused by sliding fall onto a rough surface. During abrasion the topmost layer of the skin i.e. epidermis is scraped off that exposes nerve ending resulting in a painful injury. Blood loss similar to a burn can result from serious abrasions. 2.1.3 Laceration Wound or Tears Wounds: This is the nonsurgical injury in conjunction with some type of trauma, resulting in tissue injury and damage. 2.1.4 Puncture Wounds: They are caused by some object puncturing the skin, such as needle or nail. Chances of injection in them are common because dirt can enter into the depth of wound. 2.1.5 Gunshot Wounds: They are caused by a bullet or similar driving into or through the body. 2.1.6 Penetration Wounds: Penetration wounds are caused by an object such as a knife entering and coming out from the skin. 2.2 Closed Wound: In closed wounds blood escapes the circulating system but remain in the body. It includes Contusion or bruises, heamatomas or blood tumor, Crush injury etc 2.2.1 Contusions or bruises: Bruises are caused by a blunt force trauma that damage tissue under the skin. 2.2.2 Hematomas or blood tumor: They …show more content…
The stem cells of epithelium must detach from the edges of the wound and migrate into wound. Normally dermal basal cells adhere to each other and to the underline basal layer of the dermis. Following mobilization, epithelial cells begin to enlarge and migrate down and across the wound. Transected hair follicles also contribute to the number of migrating epithelial cells. Epithelial cell migrating across wound usually move along the basal lamina or fibrin deposits, this phenomenon is called contact guidance and is an important factor in epithelial migration. Epithelial migration is followed by increased mitosis of epithelium. Recent evidence suggests that a water soluble heat labile substance called chalcone which is secreted at the wound site is responsible for regulation for mitosis