Biopolymer-containing calcium phosphate foam for bone regeneration

Hidroxyapatyte is a natural mineral found in teeth and bones. It is commonly used as a filler to regenerate bone or as a coating to promote bone growth. The application of calcium phosphate cements, which can form hydoxyapatite, in the treatment of bone defects, begun more than two decades ago and many formulations have been developed so far. The ideal bone replacing cement should be osteoconductive and osteoinductive, to stimulate bone regeneration. Moreover, it should be resorbable and gradually replaced by newly formed bone. Although most of the developed calcium phosphate cements are more resorbable than sintered hydroxypatite ceramics, they still show relatively slow resorption kinetics and in many cases the cement remains stable in the implanted site during years. The absence of interconnected macropores is indeed a limiting factor to achieve resorption. If the designed material has macropores, cells can colonize it and the access of osteoclasts is facilitated increasing the rate of healing of the bone defect.