Sintering and Characterization of Calcium Phosphate Biomaterials Elaborated from Fossilized Calcareous Shell

Abstract

Bioceramics of calcium phosphate, obtained from natural raw materials, are promising as bone substitutes because they exhibit crystallographic similarity with the bone tissue. This work deals with the sintering and characterization of calcium phosphate biomaterials from fossilized calcareous shells. Four compositions of biomaterials were prepared with Ca/P molar ratio ranging from 1.4 to 1.67. They were synthesized using a wet method and calcined at 900°C/2h providing calcium phosphate powder, then compressed into a metallic mould. The samples obtained from this compression were sintered at 1200oC for 2h. The biomaterials recovered from sintering were subjected to a microstructural characterization by scanning electron microscopy [SE and by X-ray diffraction [XR. Mechanical properties were determined by compression tests. Finally, the Arthur method was used for determining the hydrostatic density and open porosity from these biomaterials. The value of fracture strength was between 54 and 84 MPa for compositions 1.5, 1.67 and 1.6 molar and for composition 1.4 molar about 328 Mpa. The results also showed was the amount of open porosity which ranged between 35 and 54% with increasing Ca/P molar ratio. These studies demonstrate that the production of biomaterials from fossilized calcareous shells may be a new alternative to the production of biomaterials for bone reconstruction.