Objectives: Calcium phosphate ceramics are popular materials for bone reconstruction and reinforcement for a long time. Hydroxyapatite (HA), one of the calcium phosphate ceramics, has been ...successfully applied in medicine due to its excellent biocompatibility with hard tissues. Since its chemical and crystallographic properties closely resemble those of bone and tooth minerals, HA attracts a particular interest for bone grafting, augmentation in maxillofacial surgery and in orthopedics as space filling material. There is limited literature information on using bovine enamel as graft material. Moreover, there are still no attempts to use sheep enamel (and dentine) HA as a graft material. The aim of this study was to investigate the structure and the mechanical properties of bioceramics from sheep derived enamel HA. Methods: Bovine teeth were collected and cleaned from fatty tissues. Then they were subjected to calcination at ca. 850 degree C. Enamel and dentine parts were separated easily. Enamel parts were wet ball milled until fine powder (100 mu m) was produced. The dried powders were dry pressed to cylindrical green samples, suitable for compression test. The samples were sintered for 4-hours In air at several temperatures between 1000 degree C-1300 degree C. Microhardness, compression strength and density measurements along with X-ray diffraction analysis and SEM observations of the sintered samples and statistical-tests were realized. Results: The best values for compression strength and microhardness were obtained for the samples sintered at 1300 degree C, namely 100.17MPa and 368.36HV, respectively. These results agree fairly well with the density measurements as well as the crystallographic analysis and the microstructure observations. Conclusions: The comparison of the results of this study with those obtained from earlier studies where HA was derived from bovine bones (BHA) or BHA composites shows that the sheep derived enamel HA results in superb biomaterials. Moreover, this study proposes a production of HA from an economic and natural source.
