Segmental distraction osteogenesis with modified LeFort II osteotomy for a patient with craniosynostosis

In this article, we report successful orthodontic treatment combined with segmental distraction osteogenesis after a modified LeFort II osteotomy in a patient with craniosynostosis. An 8-year-old boy diagnosed with craniosynostosis had a dished-in face, an anterior crossbite, and a skeletal Class III jaw relationship because of midfacial hypoplasia. At the age of 13 years 6 months, the maxillary second and mandibular first premolars were extracted, and leveling and alignment of both arches was started with preadjusted edgewise appliances. At age 14 years 11 months, the patient had a modified LeFort II osteotomy, and the maxillary segment was advanced 7 mm and fixed to the zygomatic bone. At the same time, segmental distraction osteogenesis was started with a rigid external distraction system, and the nasal segment was advanced for 20 days at a rate of 1.0 mm per day. The total active treatment period was 40 months. As a result of the modified segmental distraction osteogenesis, significant improvement of his severe midfacial hypoplasia was achieved without excessive advancement of the maxillary dentition. Both the facial profile and the occlusion were stable after 1 year of retention. However, the nasal segment relapsed 1.4 mm during the 1.5 years after the segmental distraction osteogenesis. Evaluation of the stability and retention suggests that some overcorrection in midfacial advancement is recommended.