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

This study evaluated whether recombinant human bone morphogenetic protein-2 (rhBMP-2) can be used to regenerate a resected part of the mandible in a primate model.

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 P(GLA alone were each implanted in 1 monkey as a control. The animals were killed 16 weeks after surgery, followed by radiologic and histologic evaluation.

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.

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.