Dermabrasive scar revision. Immunohistochemical and ultrastructural evaluation

Background: Dermabrasion of facial scars 4-8 weeks after injury frequently completely eliminates visible evidence of scar formation. However, efforts to define the cellular and structural mechanisms by which this phenomenon occurs have been limited in their success. Objective: We investigated wound healing after dermabrasive scar revision. Methods: The surgical scars of seven patients were abraded 6-8 weeks after injury. Comparative electron microscopic and immunohistochemical studies were performed on punch biopsy specimens taken before and after the dermabrasion. Ultrastructural changes in the basement membrane components and dermal structures were evaluated. Monoclonal antibody staining techniques were used to observe the presence, location, and temporal expression of tenascin, epiligrin, cadherins, and integrin subunits. Results: We observed: 1) an increase in collagen bundle density and size with a tendency toward unidirectional orientation of fibers parallel to the epidermal surface, 2) an upregulation of tenascin expression throughout the papillary dermis, and 3) expression of α-6/β-4 integrin subunit on the keratinocytes throughout the stratum spinosum. Conclusions: The mechanisms by which dermabrasive scar revision alters the events of primary cicatrix formation include modification of extracellular ligand expression, thereby influencing epithelial cell-cell interaction, and reorganization of connective tissue.