Standardized qualitative evaluation of scar tissue properties in an animal wound healing model.

There is a great need to establish reproducible methods for evaluative studies of wound treatment and wound healing. Validation of the healing process through optical techniques, as well as histologic and immunohistochemical methodologies, have been improved and to some extent have become well-established assays. Data relating to biomechanical properties, e.g., evaluation of the tensile strength of scar tissue that forms in experimental wound treatment strategies, are less widely available. We chose the domestic pig as an animal model in which to examine epidermal wound healing. We implanted specially made chambers that served to isolate the wounds and prevent epidermal migration from the edges. We performed histologic and immunohistochemical analyses as well as evaluation of biomechanical qualities of scar tissue using laser tensiometry. Pig skin is well suited for wound healing studies, and wound creation, implantation of the chambers, and the regular changing of dressings could all be carried out in the operating theater. In addition to established macroscopic evaluation and microscopic documentation, the need for objective biomechanical assessment of scar tissue by measuring tensile strength has been met using laser tensiometry. By optimizing methods for measuring tensile strength, it is possible to evaluate the biomechanical quality of scar tissue formed following different courses of wound treatment, as well as histologic assessment.