This study was done to evaluate the effect of recombinant human bone morphogenic protein-2 (RhBMP-2) on enhancing the quality and quantity of regenerated bone when injected into distracted alveolar bone. Sixteen adult beagle dogs were assigned to either the control or rhBMP-2 group. After distraction was completed, an rhBMP-2 dose of 330μg in 0.33ml was slowly injected into the distracted alveolar crest of the mesial, middle, and distal parts of the alveolar bone in the experimental group. Histological and micro-computed tomography analyses of regenerated bone were done after 2 and 6 weeks of consolidation. After 6 weeks of consolidation, the vertical defect height of regenerated bone was significantly lower in the rhBMP-2 group (2.2 mm) than in the control group (3.4 mm) (P<0.05). Additionally, the width of the regenerated bone was significantly greater in the rhBMP-2 group (4.3 mm) than in the control group (2.8 mm) (P<0.05). The bone density and volume of regenerated bone in the rhBMP-2 group were denser and greater, respectively, than in the control group after 6 weeks of consolidation (P<0.001). Injection of rhBMP-2 into regenerated bone after a distraction osteogenesis procedure significantly increased bone volume in the dentoalveolar distraction site and improved both the width and height of the alveolar ridge and increased the bone density.