Will the wound granulation tissue disappear on its own?

As the wound gradually improves, new tissue will gradually begin to grow. At this time, the blood vessels and nerves of the wound will also slowly grow out. The new cells are more sensitive. If they are stimulated a little, an itchy phenomenon will occur. Many people have this feeling. As the wound gradually improves, itching will occur, so don't scratch it with your hands at this time to avoid infection.

The wound healing process

The mildest trauma is limited to the epidermis of the skin, while slightly more serious cases involve rupture of the skin and subcutaneous tissue, and wounds; severe trauma may involve rupture of muscles, tendons, nerves, and fractures. The following are the basic processes of wound healing.

1. Acute inflammatory phase

The early changes of the wound are varying degrees of tissue necrosis and blood vessel rupture and bleeding in the local area. Within a few hours, an inflammatory reaction will occur, manifested as congestion, serous exudation and leukocyte guerrilla warfare, resulting in local redness and swelling. The main white blood cells are neutrophils, which change to macrophages after 3 days. The fibrinogen in the blood and exudate in the wound quickly coagulates to form clots. The surface of some clots dries to form scabs. The clots and scabs play a role in protecting the wound.

2. Cell proliferation stage

After 2 to 3 days of wound contraction, the entire layer of skin and subcutaneous tissue at the edge of the wound moves toward the center, and the wound shrinks rapidly until it stops around 14 days. The significance of wound contraction is to reduce the wound surface. Experiments have shown that wounds can even be reduced by 80%, but the degree of wound reduction in each specific case varies depending on the animal species, wound location, wound size and shape. Wound contraction is caused by the pulling effect of newly generated myofibroblasts at the wound edge and has nothing to do with collagen. Because the time when wound contracts is exactly the time when myofibroblasts proliferate. 5-HT, angiotensin and norepinephrine can promote wound contraction, while glucocorticoids and smooth muscle antagonists can inhibit wound contraction. Inhibiting collagen formation has no effect on wound contraction, and skin grafting can stop wound contraction.

3. Scar formation stage

Granulation tissue hyperplasia and scar formation begin around the third day, with granulation tissue growing from the bottom and edges of the wound to fill the wound. Capillaries grow at a rate of approximately 0.1 to 0.6 mm per day, and their direction is mostly perpendicular to the wound surface and curved in a loop shape. There are no nerves in the granulation tissue, so there is no sensation.

4. Regeneration of epidermis and other tissues

Within 24 hours after the trauma occurs, the epidermal basal layer at the edge of the wound proliferates and moves toward the center of the wound under the clot to form a single layer of epithelium covering the surface of the granulation tissue.