A comparative study of the physical and mechanical properties of porous hydroxyapatite scaffolds fabricated by solid freeform fabrication and polymer replication method

A novel porous scaffold designed for application as a bone substitute, with a structure containing three-dimensional (3D) pore channels in a hydroxyapatite (HA) scaffold, was fabricated using a combination of a solid freeform fabrication (SFF) and cast in a mold using freezing casting method. This study was performed to evaluate the physical and biomechanical properties of the HA scaffolds fabricated by SFF and using polymer replication method (PRM), one of the conventional methods. Although the phase composition and porosity of these two scaffolds are similar, their external shape and mechanical property were different. All of the fabricated scaffolds showed similar patterns through X-ray diffraction. The difference between porosities of two HA scaffolds were not statistically significant (P>0.05). However, the average compressive strength of the scaffold fabricated by SFF was 14.6 MPa, and that of the scaffold fabricated using polymer replication was 3.56MPa (P<0.05). It was confirmed that SFF fabrication could have a relatively higher mechanical property than PRM fabrication at the same porosity.