Preparation and properties of α-calcium sulphate hemihydrate and β-tricalcium phosphate bone substitute.

Autogenous bone graft carries the risk of complications. In contrast, artificial bone graft provides initial strength and allows new bone ingrowth. In this study, we examined methods of preparation of alpha-calcium sulphate hemihydrate (alpha-CSH) and beta-tricalcium phosphate (beta-TCP), and a composite of the two materials. Characterization of the materials was determined with X-ray diffraction, differential thermal analysis (DTA), scanning electron microscopy (SEM), and porosity analysis. beta-TCP exhibited the spatial structure and porosity of normal bone with a macropore size of 50-400 mu m and some 1 mu m micropores. alpha-CSH exhibited a regular crystal structure. A combined material was prepared in a 1:1 weight ratio, and in a rabbit model, the rate of new bone mineralization was similar to that of autogenous bone graft. The combined material of beta-TCP and alpha-CSH in this study may provide similar efficacy as autogenous bone graft.