Mandibular distraction osteogenesis: a comparison of distraction rates in the rabbit model

The rabbit model has been used to study the effects of different rates of distraction upon mandibular bone. Bilateral distraction was performed at two different rates anterior to the molar teeth. Both experimental groups were significantly inferior to sham operated controls in terms of bone density (DEXA) and mechanical testing. No difference in new bone formation between the two distraction rates was detected by these modalities. However, histological examination revealed non-union to be more common in the rapidly distracted group. This suggests that attempts to shorten the duration of external fixation in clinical mandibular distraction osteogenesis should be by methods other than more rapid distraction.