Avascular necrosis in cleft maxillary repositioning: a review of cases and introduction of the 'delayed maxillary flap'.

There is a low incidence of serious complications with the Le Fort I maxillary osteotomy, but avascular necrosis is a serious problem that occurs at a higher frequency in the cleft population compared to non-cleft patients. In this retrospective study, cleft patients who had exhibited any manifestation of avascular necrosis of the maxilla following a Le Fort I advancement were identified. Five patients were found to have had vascular compromise, ranging from loss of gingival tissue to necrosis of bone and loss of teeth. In each case, possible risk factors were assessed, and secondary revision palatal surgery prior to maxillary advancement, particularly closure of oronasal fistulae with transpositional flaps, was noted to be present. Drawing on this finding and a review of the literature, clinical recommendations are made for minimizing the risk of this major complication. The use of the 'delayed maxillary flap' technique is introduced and described as a potentially beneficial procedure for cleft patients with a high risk of vascular compromise.