Stages of Wound Healing
Wound healing is a complex biological process that involves coordinated cellular and chemical responses. This process occurs in four distinct stages:
1. Hemostasis – Stopping the Bleeding
⏳ Timing: Immediately after injury, lasting about 5 to 10 minutes
🩸 Key Events:
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Constriction of blood vessels to minimize bleeding
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Activation of platelets and release of fibrin to form a clot
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Release of growth factors that trigger the subsequent healing phases
✅ Goal: Stop the bleeding and initiate the healing process
2. Inflammation – Calling for Clean-Up
⏳ Timing: From day 1 to approximately days 4–6 after the injury
🔥 Clinical Signs:
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Redness (erythema), swelling (edema), heat, and pain
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Arrival of neutrophils (defensive cells) to combat bacteria and clean the wound
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Replacement of neutrophils by macrophages, which engulf bacteria and remove dead tissue
✅ Goal: Eliminate pathogens and prepare the wound for tissue regeneration
3. Proliferation – Rebuilding the Tissue
⏳ Timing: From day 6 to day 21 after the injury
🛠️ Key Events:
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Angiogenesis: Formation of new blood vessels
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Granulation Tissue Formation: Growth of new tissue in the wound
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Wound Contraction: Reduction in the size of the wound
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Epithelialization: Migration of skin cells to cover the wound
✅ Goal: Rebuild lost tissue and restore the skin barrier
4. Maturation/Remodeling – Finalizing the Repair
⏳ Timing: From day 21 to several months after the injury
🔗 Key Events:
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Increased tensile strength of the wound and reorganization of collagen
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Conversion of soft Type III collagen into stronger Type I collagen
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Reduction of excessive blood vessels and stabilization of new tissue
✅ Goal: Complete tissue remodeling and restore skin functionality