Evaluation of the consolidation period during osteodistraction using computed tomography

The use of distraction osteogenesis offers an alternative approach to the c orrection of craniofacial deformities. However, little is known with respec t to the appropriate length of the consolidation period for the newly forme d bone. The objective of this study was to evaluate, by quantitative comput ed tomography, the regenerate bone produced during osteodistraction of the dog mandible at three different consolidation times. Twelve skeletally matu re male beagle dogs were equally separated into three experimental groups. Each dog underwent 10 mm of bilateral distraction osteogenesis to lengthen the mandible. After the distraction period, the bone was allowed to consoli date for 4, 6, or 8 weeks, at which time the animals were sacrificed and th e mandibles harvested for computed tomographic imaging. The results demonst rate a significantly lower mean bone density of the regenerate in the 4 wee k group when compared with either the 6 or 8 week groups (P < .01). There w as no significant difference, however, in mean bone density between the 6 a nd 8 week groups.