Mandibular reconstruction using a combination graft of rhBMP-2 with bone marrow cells expanded in vitro.
BACKGROUND
The aim of this study was to evaluate the efficacy of a combination graft, using recombinant human bone morphogenetic protein-2 (rhBMP-2) and culture-expanded cells derived from bone marrow, for bone regeneration in a nonhuman primate mandible.


METHODS
Five Japanese monkeys were used. Three milliliters of bone marrow was obtained from the tibia and plated into culture flasks. Adherent cells were cultured until near confluence; then, the proliferated cells were transferred to a three-dimensional culture system using collagen beads as the cell carrier. The medium was supplemented with ascorbic acid, beta-glycerophosphate, and dexamethasone to promote osteoblastic differentiation. After further proliferation on beads, the cells were mixed with a collagen sponge that was impregnated with rhBMP-2 and grafted into surgically created segmental bone defects of the mandibles. Three animals received this treatment, and either culture-expanded cells alone or collagen beads without cells were implanted into the remaining two monkeys as controls. The animals were killed 24 weeks after surgery, and the results were assessed by radiographic and histologic evaluation.


RESULTS
The combination graft of culture-expanded bone marrow cells with rhBMP-2 in a collagen sponge regenerated the mandibular bone completely. By contrast, the graft of culture-expanded cells alone resulted in only a small amount of bone formation, and the implantation of collagen beads alone led to no bone formation.


CONCLUSIONS
The combination graft of rhBMP-2 and culture-expanded cells, which requires only a small amount of bone marrow, is a reliable method for the reconstruction of segmental bone defects of the mandible.
Seto
Ichiro
I
Division of Oral Health Sciences, Department of Oral Restitution, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
Marukawa
Eriko
E
Asahina
Izumi
I
D000818:Animals; D001854:Bone Marrow Cells; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D001861:Bone Regeneration; D016723:Bone Remodeling; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D006801:Humans; D008251:Macaca; D008334:Mandible / Q000601:surgery*; D008863:Microspheres; D011994:Recombinant Proteins; D012038:Regeneration; D023822:Tissue Engineering / Q000379:methods*; D016212:Transforming Growth Factor beta
D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2