Novel bioceramic composites for bone engineering

The bioceramic composites studied for the funded project included the combinations of bioinert ceramics (alumina and zirconia), bioactive ceramics (hydroxyapatite, fluoro hydroxyapatite, bioactive glasses, and titania), biodegradable ceramics (tricalcium phosphate and calcium phosphate cement), and a biodegradable polymer (poly (lactic-co-glycolic acid)). The bioceramic composites prepared for the project were also the combinations of different material forms, e.g., dense materials, porous materials, and coating materials. The novelty of the bioceramic composites lay in the selective combinations of the different material compositions and the different material forms. Various bioceramic composites were designed and fabricated for the potential applications in orthopedics, where different mechanical properties and biocompatibility are required for either bone replacement or bone regeneration. Alumina-based composites and zirconia-based composites were studied for the project to improve the microstructures and mechanical properties without the expense of biocompatibility. It appeared that magnesia and yttria stabilized zirconia as additives could reduce the grain sizes and improve the mechanical properties. Similarly, the addition of alumina in yttria stabilized zirconia also resulted in improved microstructures and mechanical properties. Thus, the alumina-zirconia composites could find load bearing applications for bone replacement