EFFECT OF SUCRALFATE AND BASIC FIBROBLAST GROWTH-FACTOR ON FIBROVASCULAR INGROWTH INTO HYDROXYAPATITE AND POROUS POLYETHYLENE ALLOPLASTIC IMPLANTS USING A NOVEL RABBIT MODEL

This study investigated the effects of sucralfate and basic fibroblast growth factor (bFGF) on fibrovascular ingrowth into porous implant ma terials. Seven white female New Zealand rabbits underwent bilateral ab dominal incisions through which porous orbital spherical or and disc-s haped implants were inserted between their abdominal muscles. Eighty h ydroxyapatite (HA) and porous polyethylene (PP) implants, each materia l of different pore sizes, were implanted. These implants were either uncoated or coated with suspensions of polyhydroxymethylmethacrylate ( hydron); hydron and sucralfate; or hydron, sucralfate, and bFGF. Impla nts were harvested after 1, 3, or 6 weeks. Observers classified the ex tent of fibrovascular ingrowth in a blind manner using light microscop y. All discs and spheres showed fibrovascular ingrowth; at 6 weeks, al most all implants were fully vascularized. Although demonstrating diff erent degrees of fibrovascular maturity, all 3- and 6-week discs showe d complete cellular ingrowth. Overall, the most extensive and mature f ibrovascularization was found in HA implants, regardless of shape, dur ation of implantation, or angiogenic enhancing agent used. Thus, this study indicates that fibrovascular ingrowth into porous implants is mo re greatly affected by implant porosity and composition than by additi on of angiogenic enhancing agents. Further in vivo study, using other potential angiogenesis-promoting agents as well as implants with diffe rent pore characteristics, is warranted using this reliable and predic table animal model.