The biology of wound healing occurs in stages, but smaller wounds usually heal sooner than deep or large ones, according to MedlinePlus. Any type of wound, including those that occur in a sterile operating room during surgery, have the potential for infection, which can increase the size of the wound and the healing time.
Wounds are breaks or openings in the skin, and these breaks can allow entry of germs into the body, warns MedlinePlus. Deep wounds sometimes affect muscles, blood vessels, connective tissue and bones. Most cause bleeding, although burns and pressure sores do not bleed. When a wound bleeds, the blood begins to clot within a few minutes and stops the bleeding. The clot forms into a scab that seals the wound and protects the injured tissue from germs.
The body’s immune system begins working and preventing infection, so the area becomes slightly raised and pink or red in color, explains MedlinePlus. Wounds are often tender and sometimes ooze fluid, which helps to clean the injury. The blood vessels open to increase blood flow to the injury, bringing white blood cells and oxygen to speed the healing.
The body begins reconnecting blood vessels and replacing the damaged tissue over a period of several weeks, according to MedlinePlus. It begins with granulation tissue that fills the wound, and then new skin forms over the area. The edges of the wound pull inward as it heals. Eventually, the scab falls away, revealing the new scar tissue. With minor wounds, the scars may disappear over time.