Advanced Mechanical Properties of Porous Hydroxyapatite Ceramics Prepared Using Hydroxyapatite Slip and its Slurry Synthesis

There is a clinical need for synthetic scaffolds that will promote bone regeneration. Important factors include obtaining an optimal porosity and size of interconnecting macropores whilst maintaining scaffold mechanical strength, enabling complete penetration of cells and nutrients throughout the scaffold, preventing the formation of necrotic tissue in the centre of the scaffold. To address this we investigated flexural strength of bimodal porous apatite ceramics prepared using apatite slurry and its slurry synthesis was studied. Slips with different contents of HAp (K-HAp and T-HAp) and deflocculant were prepared by milling in a pot mill. The viscosity of slurries made of commercial T-HAp powder showed a drop after 3 hours’ milling, but the viscosity of slurry with high solid content of k-HAp and 2.0 wt% deflocculant increased with an increase of milling time after 2 hours’ milling. The porosity and flexural strength of the porous HAp prepared by heating the foam dipped in K-HAp slip with 2.0 wt% of deflocculant and 0.5wt% of foaming regent heated at 1200°C were 62.4 % and 14.7 MPa, and those in T-HAp were 59.7 % and 15.2 MPa with 1.5 wt% of deflocculant and 0.5wt% of foaming regent heated at 1200°C.