In this study, we examined whether quantitative bone scintigraphy can be used to assess new bone formation following distraction osteogenesis (DO). A vertical osteotomy was performed on the right hemimandible of male Sprague-Dawley rats, and a custom-made distraction device was applied. Following the gradual distraction, rats were divided into 2 subgroups, the second and fourth week. Cephalograms were taken and scintigraphic and histomorphometric analysis was performed at the second and fourth week. Scintigraphic findings showed good correlation with histomorphometric results. Results were compared with sham-operated (skin and muscle incision and placement of pin but no osteotomy) and acute distraction (5-mm acute distraction) groups. Scintigraphic mean uptake ratios were significantly higher in the gradual distraction group compared with the sham-operated and acute distraction groups. Quantitative bone scintigraphy is a promising method for the assessment of DO and consolidation. It could offer objective qualitative and quantitative data for the noninvasive evaluation of bony regenerate.