The bioceramic orbital implant: A new generation of porous implants

Purpose: The authors describe a new generation of porous orbital implant ma de of aluminum oxide (Al2O3) and compare it with the hydroxyapatite orbital implants (Bio-Eye and FCI hydroxyapatite). Methods: The authors examined the new implant macroscopically, with chemica l analysis and microscopically with scanning electron microscopy. Animal im plantation studies were performed using six adult male New Zealand albino r abbits. Implant vascularization was evaluated by means of magnetic resonanc e imaging and histopathologic sectioning. Results: The Bioceramic orbital implant was found to have very uniform pore structure with an average pore size of 500 mu m. The implant was 99.9% alu minum oxide on x-ray diffraction. Magnetic resonance imaging in vivo vascul arization studies demonstrated enhancement of the implant to its center by 4 weeks after implantation in the rabbit. Histopathologically, fibrovascula rization occurred uniformly throughout the implant and was noted by 4 weeks . Conclusions: The Bioceramic orbital implant represents a new porous orbital implant that has a very regular and extensive interconnected pore system, is as biocompatible as hydroxyaparite, is easy to manufacture, structurally strong, and free of contaminants. It is manufactured with no disruption to marine life ecosystems as may occur in the harvesting of coral for other o rbital implants. It is less expensive than currently available hydroxyapati te implants and was approved by the U.S. Food and Drug Administration in Ap ril 2000.