Fabrication of biphasic calcium phosphate foam granular and its initial evaluation using beagle dogs

Biphasic calcium phosphate foam consisting of core αTCP covered with carbonate apatite (CO₃Ap) was fabricated based on the compositional transformation by exposing αTCP foam to (NH₄) ₂HPO₄ aqueous solution at 200 °C for 90min in order to understand the effect on bone formation rate and granule remaining ratio. The BCP foam was gently crushed and sieved to prepare foam granular. Bone defects made at the mandible of beagle dog were reconstructed with αTCP, BCP and CO₃Ap foam granular. 3 months after surgery, bone reconstruction rate of the BCP and CO₃Ap were 159.7±28.6% and 169.0±29.7% whereas those of αTCP and blood clot group were 89.5±14.7% and 85.2±13.2%, respectively, and no further increase was observed at 6 month. On the other hand, granular remaining ratio was 3.0±1.7%, 3.1±1.8%, 6.9±2.0% for BCP, αTCP and CO₃Ap foam granular, respectivly. We concluded therefore, BCP foam granular could be an ideal bone substitute since it alllows large porosity, at least similar bone formation ratio to CO₃Ap and faster replacement to bone.