Laser treatments accelerate each of the three phases associated with the natural healing of wounds: inflammation, proliferation and remodeling. The result is a reduction in pain, inflammation reduction, increased stimulation of connective tissue (granulation tissue) and increased capillary production (angiogenesis) leading to improved blood flow during proliferation.
Despite the pain associated with this stage, the inflammatory phase is necessary for tissue repair. First, in the area of the wound, there appear platelets and white blood cells to coagulate the blood and stop blood loss.. Next, anincreased number of macrophages clean the area and remove dead tissue by engulfing and destroying foreign matter and damaged cells. Macrophages also release products (known as "factors") that stimulate proliferation - the second step of wound healing.
This is the formation of "granulation tissue". There is an activation of fibroblasts and angiogenesis. Angiogenesis is the production of new capillaries (small blood vessels). Fibroblasts are connective tissue cells that form the basis of new tissue. A special kind of fibroblast is the myofibroblast. This cell can contract itself like a smooth muscle cell and in this manner diminish the surface size of the wound.This process is known as collagen synthesis.
This is the final step of wound contraction, where the tissue starts to contract and return to its normal appearance.
What happens when a laser is placed on an open wound?
Laser treatment accelerates the different healing phases, preserving only the necessary components of the inflammatory phase, resulting in a shorter inflammatory reaction causing less pain. Laser stimulates the fibroblasts during the proliferation phase, speeds up angiogenesis and causes temporary vasodilation (blood vessels increase in diameter).
Greater blood flow equals more efficient delivery of oxygen and fuel molecules to the area and a faster removal of waste products; thus allowing a greater production of adenosine triphosphate (ATP) - the basic energy source of a cell. In angiogenesis, the final result is a greater production of blood vessels through the growth of new tissue. Laser also accelerates the absorption of a haematoma through the stimulation of prostacyclin.