Examination of expanded polytetrafluoroethylene wound healing models

Abstract
The object of this animal study was to examine and further develop the expanded polytetrafluoroethylene wound healing model. The goal was to increase its potential for assessing wound healing by increasing yield, reducing variability, establishing the elements of a standard technique, and further testing its ability to detect variations of healing which have clinical significance. Expanded polytetrafluoroethylene implants of various dimensions and fabrications and several implantation and sterilization techniques were compared in rats. Hydroxyproline, DNA, and protein deposition into the expanded polytetrafluoroethylene implants as parameters for wound healing were assessed. Additionally, a 4 cm skin incision for tensile strength assessment was created. Wound healing was assessed under normal and corticosteroid-impaired healing conditions. The highest yield of collagen was found in the stiffer fabrication of expanded polytetrafluoroethylene with the larger pore size and after the more traumatic implantation technique of incisional placement. Variability was unaffected by fabrication, implantation technique, indexing by various geometric dimensions of the implant, sterilization, or sampling techniques. Variability was the same in the individual animals as in groups of animals. The expanded polytetrafluoroethylene method also detects the influence of antiinflammatory corticosteroids and reflects the tensile strength of incisional wounds made in other sites in the same animal.