Preparation and properties of α-calcium sulphate hemihydrate and ß-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 α-calcium sulphate hemihydrate (α-CSH) and ß-tricalcium phosphate (ß-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. ß-TCP exhibited the spatial structure and porosity of normal bone with a macropore size of 50-400 µm and some 1 µm micropores. α-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 ß-TCP and α-CSH in this study may provide similar efficacy as autogenous bone graft.

[Microsurgical repair of syndactyly of the fingers in children].

OBJECTIVE: To evaluate the effectiveness of microsurgical technique for repairing syndactyly of the fingers in children. METHODS: Microsurgical repair of syndactyly of the fingers was performed in 32 children. The skin joining the syndactyly was incised and relaxed under microscope, and dorsal metacarpal flap of comparable size was used to repair the lateral skin defect of the finger and also to reconstruct the finger web. RESULTS: All the flaps survived without scar leaving on the lateral skin of the fingers, and the reconstruction of the finger web was satisfying. CONCLUSION: Microsurgical technique is applicable in the surgical repair of syndactyly of the fingers in children.