IMMUNOHISTOCHEMICAL STUDIES ON THE DISTRIBUTION OF ALBUMIN, FIBRINOGEN, FIBRONECTIN, IGG AND COLLAGEN AROUND PTFE AND TITANIUM IMPLANTS

Time-dependent distribution of extracellular proteins (albumin, fibrin ogen, fibronectin, collagen-1 and IgG) in the interface zone between i mplant and soft tissue has been investigated utilizing a recently deve loped method. Commercially pure (c.p.) titanium and polytetrafluoroeth ylene (PTFE) implants were inserted in the abdominal wall of rats for 1, 6 and 12 weeks followed by a mild fixation, cryoprotection, rapid f reezing in LN(2)-cooled propane, cryosubstitution and low-temperature infiltration with UV curing of the methacrylate LR-Gold. Before sectio ning, the bulk part of the titanium was removed by an electrolytical d issolution technique (electropolishing), while the PTFE implants were removed by a fracture technique. Employing a cryosubstitution method c ombined with postembedding immunohistochemistry, a light microscopic a nalysis was allowed. The selected proteins had an apparently varying d istribution in the implant-close tissue and their distribution changed during the follow-up period. There was also a difference in the distr ibution pattern for each protein around titanium and PTFE implants. In sertion of the c.p. titanium implants elicited an inflammatory reactio n in many respects similar to a normal wound healing response, while t he PTFE implants caused a more pronounced, persistent inflammation. (C ) 1996 Elsevier Science Limited.