Discussion

Abstract

There should be no doubt in the oral and maxillofacial surgeon's mind at this time that maxillary advancement surgery of any kind in the severely maxillary deficient patient will improve the facial profile, nasal projection, and, if aligned properly, improve function. Research and case reports have shown that when a patient requires more than 10 mm of anterior repositioning, there is a higher potential for relapse. The challenge of maintaining a stable result, even with the advent of rigid fixation and bone grafting, remains a challenge. This is especially true if accompanied by an inferior movement as well. One possible cause may be the fact that the soft tissue envelope of the maxilla may not tolerate such large movements. During the healing process, the scar tissue formation may overcome the stability of the bone plates, leading to relapse and possibly malocclusion. We have certainly learned this from segmental maxillary surgery in which the maxilla needed to be widened more than 7 mm. Our group has found that these patients obtain a more stable result with surgically-assisted palatal expansion first (“transverse distraction osteogenesis”). Secondary repositioning of the maxilla and mandible are done to deal with the vertical, midline, and anterioposterior movements at a second procedure.