Development of biphasic hydroxyapatite/dicalcium phosphate dihydrate (DCPD) bone graft using polyurethane foam template: in vitro and in vivo study

Abstract

In this research, we characterise a new porous calcium phosphate composite composed of hydroxyapatite (HAp) and dicalcium phosphate dihydrate (DCPD) prepared by foam casting method using polyurethane foam, designed for osteoconductive and osteoinductive scaffolds. According to the obtained results, the values of elastic modulus, compressive strength and density of the samples reduced with increasing percentage of DCPD phase. The mechanical properties of the prepared samples were near the natural compact bone. After in vitro examination and confirming the bone-like apatite ability of the prepared composites, in vivo examination was employed, and for this purpose, a rabbit model was developed. New bones formed on the outside surface and on the macropore walls of the samples, as osteoids and osteoclasts, were evident 2 months post-operatively. Considering these properties, the prepared composite scaffolds made from HAp and DCPD could be considered as highly bioactive and potential bone tissue engineering implants.