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The human body can sustain a variety of injuries such as burns, cuts, and knocks or bangs. Well, all of these aggressions initiate an orderly sequence of steps that are involved in the healing response, in which the normal functional tissue (skin) is replaced by connective tissue (scar). The healing response is also characterized by the movement of specialized cells into the injury site.

The restoration of anatomical continuity and function is the result of the complex and dynamic process of healing. Following an injury, your body can respond in 4 different ways:

1.Regeneration (exact replacement)

Regeneration happens when there is loss of structure and functionality. The beauty of our organism is that it has the complex ability to restore that tissue by replacing exactly what was there before the damage. Smaller forms of life, such as the salamander and crab, can regenerate tissue in this way. Throughout the past million years, we have lost this ability and can only recover a limited amount of damaged tissues by the process of regeneration.

2. Normal repair (reestablished equilibrium)

Normal repair is the instance where there is a re-established equilibrium between scar creation and scar remodeling. This is the typical response that most humans experience following an injury. The abnormal response to tissue damage stand in sharp contrast to the healthy repair response.

3. Excessive healing (fibrosis and contractures)

In excessive healing there is an exaggerated accumulation of connective tissue; this produces an altered tissue and, thus, loss of functionality. Fibrosis, structures, adhesions and contractures are examples of exaggerated healing. Keloids and hypertrophic scars in the skin are examples of fibrosis. Contraction is normal during the process of healing but if exaggerated, it becomes pathologic and is known as a contracture.

4. Deficient healing (chronic ulcers)

Deficient healing is the opposite of fibrosis; it exists when there is an abnormally low deposition of connective tissue matrix and the tissue is weakened to the point where it can fall apart. Persistent non-healing ulcers are examples of deficient healing.

The Skin's Natural Regenerative Process

Just as an injury occurs, several different cells are sent to the damaged site, and the complex healing process begins.

The normal healing cascade commences with an coordinated process of hemostasis and fibrin accumulation, which leads to an inflammatory cell cascade, characterized by neutrophils, macrophages and lymphocytes within the damaged tissues. This is followed by attraction and proliferation of fibroblasts and collagen accumulation, and finally remodeling by collagen cross-linking and scar maturation. Despite this coordinated sequence of steps responsible for normal wound repairing, abnormal responses leading to fibrosis or chronic ulcers may happen if any part of the healing sequence is altered.