The use of bifocal distraction osteogenesis for the treatment of continuity defects in the rabbit mandible /

A prospective, randomized, experimental study was performed to assess the treatment of mandibular continuity defects by distraction osteogenesis, using the rabbit model. This method of treatment was compared to a control group, which had treatment by traditional means, using a fixation plate. Eight animals were randomized into one of the two groups.The treatment methods were assessed by clinical, radiographic, and histologic examinations.Clinically, the experimental specimens had greater dimensions of bone formation in the defects than their matched controls.Radiographically, there was a higher percentage of radiopacity in the defects of the experimental group compared to the controls, although not statistically significant.Histologically, there was a statistically significant higher percentage of bone fill in the defects of the experimental group compared to the controls. Three of the four experimental specimens (75%) developed bony union at the 'docking site'.A cost-efficient animal model was developed for the study of bifocal distraction in the treatment of mandibular continuity defects. The critical-sized mandibular defect in the rabbit model was found to be a minimum of 4mm