Treatment of severe mandibular prognathism and maxillary hypoplasia with severe midline discrepancy: A case report

Class III malformations are the corollary of insufficient forward growth of the maxilla, excessive forward mandibular growth or a combination of both. It is often combined with excessive vertical growth and less frequently with insufficient vertical development. In many instances, sagittal split osteotomy is the method of choice for mild to moderate mandibular prognathism. However, it has been suggested that the sagittal split method is contraindicated in cases of mandibular prognathism with severe anterior open bite, and requiring more than 8–10 mm of mandibular posterior repositioning. This operative technique appeared very unstable and the results were unpredictable. Bilateral sagittal split ramus osteotomy result depended on the ability of the surgeon to position correctly the two proximal fragments during intervention under general anaesthesia. Moreover, with a large mandibular setback, the risk of inducing obstructive sleep apnoea was high. This case report highlights the successful management of a 19-year-old female with skeletal class III malocclusion with open bite by combined orthodontic surgical treatment, where correction was done during bi-jaw surgery not only to correct the skeletal malformations but also to correct the midline deviation without extraction of teeth.