Open bite: stability after bimaxillary surgery - 2-year treatment outcomesin 58 patients

Stability after bimaxillary surgery to correct open bite malocclusion and m andibular retrognathism was evaluated on lateral cephalograms before surger y, 8 weeks post-operatively, and after 2 years. The 58 consecutive patients were treated to a normal occlusion and good facial aesthetics. Treatment i ncluded the orthodontic alignment of teeth by maxillary and mandibular fixe d appliances, Le Fort I osteotomy, and bilateral sagittal split ramus osteo tomy. Twenty-six patients also had a genioplasty, Intra-osseous wires or bi cortical screws were used for fixation. Twenty-three patients had maxillo-m andibular fixation (MMF) for 8 weeks or more, six for 4-7 weeks, 14 for 1-3 weeks, and 15 had no fixation. At follow-up 2 years later, the maxilla rem ained unchanged and the mandible had rotated on average 1.4 degrees posteri orly. Seventeen patients had an open bite. Among them, eight patients had u ndergone segmental osteotomies. The relapse was mainly due to incisor procl ination. The most stabile overbite was found in the group with no MMF after surgery.