[Repair of the connective tissue in a non-sutured skin wound]

During the healing of a second intention wound, granulation tissue is built up during the inflammatory and detersive phase which commences in the wound edges as soon as the loss of substance is created. Granulation tissue becomes scar tissue via connective and vascular proliferation and epidermization takes place concurrently. The origin of the fibroblasts composing the granulation tissue is debated: monocytes or fibroblasts from the wound edges? Ultrastructural and immunohistochemical data from studies of experimental wounds in the pig and the monkey make it possible to determine their origin and follow their progress. These cells originate from the fibroblasts of the wound edges and become undifferentiated cells which multiply and migrate to reach the loss of substance. There they become activated fibroblasts and contribute to repairing the loss of substance by secreting fibronectin and type I and type III collagen. As differentiated fibroblasts and myofibroblasts, they remodel and contract scar tissue.