Based on extrusion deposition and foaming technique, a novel method for biological hydroxyapatite (HA) scaffolds was introduced in this paper. The scaffolds were primarily characterised by interconnected and hierarchically porous structures with high porosity, adjustable distribution of pore sizes, as well as considerable mechanical strength. In order to confirm that fine control of bulk porosity and mechanical strength was possible and feasible, further analysis of obtained scaffolds was carried out by field emission scanning electron microscope (FESEM), compressive test and calculation of volumetric shrinkage; in particular, the additional porosity resulting from the introduction of pore former was evaluated. The results indicated that this method can have a great potential to construct HA scaffolds of suitable quality for spongy bone in bone tissue engineering.
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