Enhanced bone regeneration in variable‐type biphasic ceramic phosphate scaffolds using rhbmp‐2

Our aim was to investigate the bone regeneration capacity of powder‐type biphasic ceramic scaffold (BCP powder), block‐type BCP (BCP block), and collagen‐added block‐type BCP (BCP collagen) with different concentrations of recombinant human bone morphogenetic protein 2 (rhBMP‐2) in an animal model. Four rabbits were assigned to each of the following groups: no graft + rhBMP‐2 (0.1/0.2 mg/mL), BCP powder + rhBMP‐2 (0.1/0.2 mg/mL), BCP block + rhBMP‐2 (0.1/0.2 mg/mL), and BCP collagen + rhBMP‐2 (0.1/0.2 mg/mL), i.e., a total of 32 rabbits. Polycarbonate tubes (Φ 7 mm × 5 mm) for supporting scaffolds were fixed into a 7 mm round border. Subsequently, 0.1 mL of rhBMP‐2 solutions with different concentrations was injected into the tubes. Both radiological and histomorphometric analyses showed that osteogenesis was not enhanced by increasing the con-centration of rhBMP‐2 in all groups at both 3 and 6 weeks. Radiological analysis showed that bone formation was higher in the BCP collagen group than in the BCP powder and BCP block groups at both rhBMP‐2 concentrations at 3 weeks. rhBMP‐2 enhanced bone formation; however, as the con-centration increased, bone formation could not be enhanced infinitely. Collagen‐added alloplastic graft material may be useful for mediating rapid bone formation in initial stages.