Fabrication of low crystalline B-type carbonate apatite block from low crystalline calcite block

Low crystalline B-type carbonate apatite (CO3Ap) block was fabricated by compositional transformation based on dissolution–precipitation reaction using microporous low crystalline calcite block as a precursor. In other words, microporous low crystalline calcite block prepared by carbonation of Ca(OH)2 compact was phosphoridated by exposing to 1 mol·dm−3 Na2HPO4 solutions at 60°C for 14 days. XRD, FT-IR and SEM analysis showed that calcite block completely transformed into B-type CO3Ap keeping its macroscopic morphology. Diametral tensile strength of the low-crystalline B-type CO3Ap block was approximately 5.4 MPa, and this value was much higher when compared with the low-crystalline calcite block, 0.73 MPa. Low crystalline B-type CO3Ap block fabricated in this method could be an ideal bone replacement due to its close similarity in its inorganic chemical composition and crystallinity to bone.