Epidermal and fibroblast growth factors enhance fibrovascular integration of porous polyethylene implants

Purpose: Porous implants used in functional and aesthetic reconstruction of the orbit, face, and cranium are less likely to develop complications afte r they become biointegrated. We investigated whether the administration of exogenous growth factors could increase the rate of implant integration. Methods: High-density porous polyethylene cubes were placed in dorsal paras pinal muscles of rabbits, and daily transcutaneous injections of saline, ep idermal growth factor, or basic fibroblast growth factor were administered directly over the cubes: fur 10 days. At serial time points up to 10 weeks, cubes were explanted and the fibroblasts present at the center of the cube s were counted. Results: Injections of epidermal growth factor and basic fibroblast growth factor increased the rate at which fibroblasts accumulated in porous polyet hylene implants and decreased the time required to achieve a maximal rate o f cellular accumulation within the cubes. At 4 weeks, when all cell populat ions had attained a linear I ate of accumulation, cubes previously injected with saline, epidermal growth factor, or basic fibroblast growth factor co ntained an average of 10, 40, and 80 cells per 0.0156 mm(2), at their cente rs. respectively. Conclusions: Enhancement of the rate of biointegration of porous poly-ethyl ene cubes in rabbits is achievable by repeated, transcutaneous administrati on of exogenous growth factors.