OBJECTIVETo evaluate the effect of basic fibroblast growth factor (bFGF) treated collagen composite sponge on vascularization of HA orbital implants.

METHODSNew Zealand rabbits received three different orbital implants:naked implants, implants wrapped with collagen composite sponge and implants wrapped with bFGF treated collagen composite sponge.Implants were harvested 2, 4, 6, 8 and 12 weeks after surgery. The vascularization of implants was then assessed by light and electron microscopy.

RESULTSAt post-surgery weeks of 2, 4 and 6, bFGF treated collagen composite sponge induced the highest degree of vascularization of orbital implants. Collagen composite sponge alone resulted in higher extent of vascularization than naked implants. Complete vascularization of implants was observed at post-surgery 6 weeks by bFGF treated collagen composite sponge, which was not observed in the other two groups until post-surgery 8 weeks. There were significant differences in the average length of fibrovasculature and in the degree of vascularization among each group at post-surgery 2, 4 and 6 weeks (P<0.05), while no statistical difference was observed at post-surgery 8 and 12 weeks (P>0.05).

CONCLUSIONSbFGF treated collagen composite sponge facilitates fibrovascularization of orbital implants, and shortens the time required for complete vascularization. Collagen composite sponge alone promotes early-stage fibrovascularization, but fails to facilitate complete vascularization of orbital implants.