The Science of Wound Healing

Regardless of size or type, all wounds should follow the same path to healing. Scientific research typically refers to wound healing as a series of overlapping phases. While the body’s complex healing mechanisms occur simultaneously individual areas of a wound may respond at different rates.
Often impediments or complications can slow or halt the healing process in the inflammatory phase of healing. A thorough understanding of the factors affecting wound healing is essential to achieving wound closure. The following information examines some of the elements involved in wound healing.

The Wound Healing Path

Three different views of the wound healing response

Clinical View

Native collagen application to wound.

Open abdominal wound, measuring 7x3x3.6cm.

Day 0-1

Day 0-1- laboratory Leukocytes infiltrate from the underlying tissue to clean up the wound.
  • Damaged vessels constrict to slow blood loss.
  • Uninjured vessels permeate and release serum, proteins, and platelets.
  • Platelets aggregate to stop bleeding.
  • Leukocytes migrate into the tissue and initiate the inflammatory process.

Reduced size of wound, measuring 4x1.2x1.5cm.

Day 0-14

Day 0-14 – laboratory New blood vessels grow into the wound to restore circulation.
  • Neutrophils secrete chemicals that kill bacteria and mediate inflammatory activities.
  • Monocytes emigrate to the wound and are transformed into macrophages.
  • Macrophages engulf and digest foreign particles and necrotic debris., including cellular remains.
  • Macrophages release angiogenic substances resulting in the growth of new capillaries and granulation tissue.

Reduced wound size measuring 1.3x0.4x0.5cm.

Day 1-35

Day 1-35 – laboratory Macrophages and fibroblasts are present in the wound.
  • Fibroblasts proliferate in the wound and secrete glycoproteins and collagen.
  • Epidermal cells begin to migrate from the wound edge.
  • Granulation tissue is formed from macrophages, fibroblasts, and neovasculature.

Wound Closure. Day 49

Day 5- 90

Day 5- 90 – laboratory Fibroblasts migrate into the wound from surrounding tissue and deposit new collagen fibers. Epidermal cells close the wound.
  • Fibroblasts secrete collagen which provides strength to the wound.
  • Wound remodeling occurs with the deposition of organized fibers.
  • Wound contracture occurs, increasing tissue Integrity.
  • Epidermal cells grow over the connective tissue bed to close the wound.


“I’ve been a disciple of occlusive wound healing ever since”.
Ira Davis, MD
Department of Dermatology
Westchester County Medical Center
Valhalla, New York
Wound care has changed rapidly since I began my Dermatology training at Duke University. At the time, occlusive dressings were just the beginning to play a significant role in the clinical management of chronic wounds. As a medical student, I utilize wet to dry dressings to treat chronic wounds.
As a Dermatology resident in the light 1980s, I was exposed to advancements and wound healing at Dr. Claude Barton’s Leg Ulcer Clinic at Duke University. In those days, we didn’t have many dressing choices and we utilized occlusive dressings as well as modified Unna’s boots. These methods helped us heal chronic ulcers, and in some cases, enable patients to avoid amputation. It was gratifying to close previously non-healing wounds and help patients enjoy an improved quality of life. I’ve been a disciple of occlusive wound healing ever since.
I treat chronic, non-healing lesions by first determining the etiology of the problem. Then I implement corrective action by selecting a treatment from the broad range of options now available to clinicians. For example, depending on the tissue present in the wound, I will utilize various occlusive dressings. There are also promising Type 1 collagen-based dressings available which may offer a unique methodology to enhance wound healing.
Wound management has advanced significantly since my days as a student using wet-to-dry dressings. Now clinicians have a product armamentarium so diverse that they can select a treatment based on wound clinical characteristics and a dressing’s beneficial attributes.