Enhanced Degradation and Osteogenesis of β-Tricalcium Phosphate/Calcium Sulfate Composite Bioceramics: The Effects of Phase Ratio

The beta-TCP/CaS composites were hydrothermal synthesized at various ratios using bovine trabecular bone and CaS (CaSO4 center dot H2O) powder. The performance of the composites degradation as well as osteogenesis were then evaluated in vitro and in vivo. It was shown that the beta-TCP/CaS composites overcame the drawback of beta-TCP (degrading too slowly) and CaS (degrading too fast). Furthermore, the in vitro and in vivo degradation rates of the composites increased with increasing CaS. It was also shown that combining CaS and TCP enhanced the osteogenic activities, most likely due to a better match between the rates of degradation and new bone formation. Furthermore, the composites had a self-setting feature, which benefited the defect repair with complex-shapes. Our study further suggested that beta-TCP/CaS composites could be a useful substitute for the bone defect therapy with the phase ratio as an important factor affecting the performance of TCP/CaS composite bioceramics.