Sintering effects on physico chemical properties of bioactivity of natural and synthetic hydroxyapatite

The behaviour of the natural Hydroxyapatite (N-HA) prepared from bovine bones and synthetic hydroxyapatite (S-HA) was studied. The sintering effects on the structure and on the kinetic of bioactivity of natural and synthetic hydroxyapatite were highlighted. Obtained results show some differences between these biomaterials. XRD patterns showed that the crystallographic structure of pure N-HA was not affected by the sitering at different temperatures when several modifications in S-HA were registered. To evaluate their kinetic of bioactivity, ICP-OES method was employed. The experimental results show that the kinetic of bioactivity of N-HA increases with the sintering temperature. Consequently, the new phosphate phase was formed with higher thick on the surface of granules sintered at high temperatures. However, in S-HA, the formation of bone like apatite is very sensitive to phase's existent at any sintering temperature. The formation of TCP has favourites and activates the formation of new phase.