Analysis of the performance of different orthodontic devices for mandibular symphyseal distraction osteogenesis

The results showed that the hybrid device was the most stable appliance under mastication loads, followed by the tooth- and bone-borne devices. However, parasitic rotations of the mandibular arms caused by mastication might counteract the benefits of distraction. The tooth-borne device was found to have the highest reliability in transferring expansion to the mandibular bone. For this device, mandibular expansion was less than the nominal aperture of the distractor by no more than 15 per cent. Lower values of reliability were achieved with the bone-borne device. As the values of the aperture of the appliances increased, the stability guaranteed in the fracture gap increased while the reliability in transferring expansion to the mandibular arch decreased.