A novel modification for polymer sponge method to fabricate the highly porous composite bone scaffolds with large aspect ratio suitable for repairing critical-sized bone defects

In this paper, a modified version of the polymer sponge method is proposed to fabricate some porous composite bone scaffolds consisting of hydroxyapatite (HA) and alumina. Findings of the current paper show that the modified polymer sponge scheme presented in this study results in the scaffolds with superior physical and mechanical properties in comparison with the classical foam replica technique which is commonly used in the literature. Scaffolds with the total and open porosity of 75.22 +/- 2.97% and 68.19 +/- 1.61%, respectively, were achieved by the proposed method. Furthermore, the value of the compressive strength of the fabricated scaffolds was 4.25 +/- 0.73 MPa which is good for bone tissue engineering applications. The innovative scheme presented in this paper makes it possible to produce the samples with the large aspect ratio which are suitable for repairing critical-sized bone defects.