Reconstruction of the primate mandible with a combination graft of recombinant human bone morphogenetic protein-2 and bone marrow

Purpose: This study evaluated whether recombinant human bone morphogenetic protein-2 (rhRMP-2) can be used to regenerate a resected part of the mandible in a primate model. Materials and Methods: Segmental bone defects were created surgically in the mandible of Japanese monkeys. rhBMP-2 was suspended in a solution of polyglycolic co-lactic acid (PGLA) and lyophilized to make a BMP/PGLA complex. The rhBMP-2/PGLA complex and autogenous bone marrow in ratios of 3:0, 2.5.0.5, or 2:1 (vol:vol) were each implanted into the bone defects in 3 monkeys. Bone marrow or PGLA alone were each implanted in I monkey as a control. The animals were killed 16 weeks after surgery, followed by radiologic and histologic evaluation. Results: The implantation of bone marrow alone succeeded in reconstruction of the mandible, but the implantation of the rhBMP-2/PGLA complex showed only a small amount of bone formation. The combination graft of rhBMP-2/PGLA and bone marrow resulted in a greater degree of bone formation; especially the 2:1 combination showed the same result as only bone marrow implantation. Conclusion: The combination graft of rhBMP-2 and bone marrow, which requires only a small amount of bone marrow, was a reliable method for reconstruction of mandibular segmental defects in this animal model. (C) 2001 American Association of Oral and Maxillofacial Surgeons.