Clinical meaning
Surgical wounds are classified by their method of closure into three categories of wound healing intention. Primary intention healing occurs when wound edges are directly approximated (sutured, stapled, or taped together) with minimal tissue loss; this produces the fastest healing with the least scar formation and lowest infection risk. Examples include clean surgical incisions, laceration repairs, and cesarean section wounds. Secondary intention healing occurs when wounds are left open to heal from the base upward through granulation tissue formation; these wounds have significant tissue loss and cannot be approximated. Examples include pressure injuries, burns, and wounds left open after abscess drainage. Tertiary intention (delayed primary closure) occurs when a contaminated wound is initially left open for several days to allow infection to resolve or edema to decrease, then surgically closed with sutures. The wound healing process itself follows four overlapping phases: hemostasis (immediate; platelet plug and fibrin clot formation), inflammatory phase (days 1-6; neutrophils and macrophages remove debris and pathogens, vasodilation causes erythema, warmth, and edema), proliferative phase (days 4-24; fibroblasts produce collagen, angiogenesis creates new blood vessels, granulation tissue...