Evaluation of the acute scarring response to the implant of different types of biomaterial in the abdominal wall

Since the short-term, acute scarring process induced by a biomaterial may c ondition the evolution of the repair process, the present investigation eva luates the behavior of polytetrafluoroethylene (PTFE) and polypropylene (PL ) biomaterials in the initial stages of repair. Three PTFE biomaterials (My cro Mesh(R), Dual Mesh(R) and Soft Tissue Patch(R)) and one PL biomaterial (Marlex(R)) were employed to repair defects created in the abdominal wall o f New Zealand rabbits. Animals were sacrificed at 3 or 7 days. Specimens we re obtained for light and scanning electron microscopy, and immunohistochem ical analysis using the RAM-11 monoclonal antibody for rabbit macrophages. The PL implants showed substantial adhesion formation with viscera. Lower a dhesion formation was detected in the PTFE implants. The evolution of the a cute phase of the repair process was similar for each PTFE biomaterial. At 3 days post implant, an incipient neoperitoneum was detected which was full y established after 7 days. The behavior of the PL implant was similar, alt hough a greater amount of reticular granulation was detected. The neoformed peritoneum was irregular. Few RAM-11-labeled macrophages were detected in all cases. The acute phase of the tissue repair process induced by the impl ant of PTFE and PL biomaterials generally proceeds along similar lines to a normal repair process. However, the use of microporous, laminar materials seems to favor the early establishment of a well-defined neoperitoneal laye r. (C) 2000 Kluwer Academic Publishers.