DISTRACTION OSTEOGENESIS TO WIDEN THE MANDIBLE

The purpose of this investigation was to ellucidate the biology of dis traction osteogenesis during mandibular widening. Midsymphyseal vertic al interdental osteotomies were performed in nine Macaca mulatta monke ys. After a latency period a tooth-borne appliance was activated at a rate of 0.5 mm twice a day for 7-10 days. The appliance was then stabi lized for a period of 4 or 8 weeks. The distraction gap at the inferio r portion of the symphysis was bridged completely by new bony trabecul ae. Bone formation in the interdental area was apparently related to t he surgical technique. Newly formed bony trabeculae were oriented para llel to the direction of distraction. The location of the osteotomy si te with an adequate margin of alveolar bone contiguous with the adjace nt teeth was necessary for the induction of the distraction osteogenes is. Disproportional movement between superior and inferior portions of the distracted segments was noted.