Effects of hydrothermal treatment temperature on the crystallinity of cancellous bone type carbonate apatite foam

We have previously reported that the carbonate apatite (CAP) foam that has similarities in both inorganic chemical composition and morphology to cancellous bone could be prepared from α-tricalcium phosphate (α-TCP) foam by the hydrothermal treatment with Na₂CO₃ at 200°C for 24 hrs. However, the crystallinity of the CAP foam was much higher than that of bone. In order to prepare CAP foam similar to cancellous bone in crystallinity as well as its inorganic composition and morphology, this study attempted to prepare CAP foam at lower temperature. Hydrothermal treatment at 100°C allowed low-crystalline CAP foam whereas longer period was imposed for complete conversion of α-TCP foam into CAP foam.