HISTOLOGIC-STUDY OF LIVING RESPONSE TO ARTIFICIALLY SYNTHESIZED HYDROXYAPATITE IMPLANT - 1-YEAR FOLLOW-UP

We implanted artificially synthesized hydroxyapatite spheres into the orbits of 13 rabbits after enucleation. The spheres were removed 1, 2, 3, 6, and 12 months after implantation and examined by light and scan ning electron microscopy. Tissue breakdown and exposure of the artific ially synthesized hydroxyapatite implants were not observed. Month aft er month, fibrovascular tissues gradually invaded the pores of the art ificially synthesized hydroxyapatite spheres deeper and deeper. Althou gh the hydroxyapatite we used was completely artificially synthesized, we observed a mild foreign-body reaction around the artificially synt hesized hydroxyapatite spheres. After 12 months, however, relief of th e foreign-body reaction had occurred. Hydroxyapatite spheres for orbit al implants after enucleation without scleral enveloping are appropria te.