Can combined maxillomandibular distraction osteogenesis avoid bilateral sagittal split osteotomies?

Abstract

Background: Maxillary expansion and transversal maxillary distraction osteogenesis are becoming increasingly popular approaches in orthognathic surgery. Intraoral transversal mandibular distraction (TMD) osteogenesis procedures are utilised in many cases of transverse mandibular deficiency with dental crowding of the mandibular anterior teeth in class I, II and III malocclusions. Dental and skeletal positional changes after TMD were studied prior to osteotomies on patients with diverse malocclusions. Le Fort I advancement, trans palatal distraction (TPD) and TMD were performed both together or in later cases separately starting with the TMD followed by TPD, Le Fort I about 4 weeks later. Methods: We sought to determine the facial aesthetic amelioration and the subsequent degree of mandibular advancement resulting in an adequate realignment of the dental arch. We also note that these changes result in a change in the facial mask both anteroposteriorly and transversally. Findings: The facial aesthetic modifications after TMD were evaluated with cephalometric analysis, computed tomography scan, three-dimensional analysis and photographic data in 50 patients. Conclusions: The combination of TMD with or without repositioning of the maxilla (Le Fort I) and TMD allows a relatively good restoration of the facial structure and harmony. In most cases we were able to avoid a bilateral sagittal split osteotomy due to significant mandibular lengthening.