[Distraction osteogenesis of the mandibular ramus in hemifacial microsomia].

[OBJECTIVE] To study the application of distraction osteogenesis (DO) of the mandibular ramus in hemifacial microsomia.

[METHODS] From 1999 to 2006, 15 patients with hemifacial microsomia were treated with DO of the ramus, including 12 cases of children and juveniles, 3 cases of grown-ups. Maxillary Le Fort I osteotomy, unilateral sagittal split ramus osteotomy, genioplasty and free scapular flaps were selected to perform on the first or secondary stage of treatment.

[RESULTS] Successful distraction was achieved in all patients with an average distraction distance of 21.25 mm. The distractor was removed after consolidation proved by clinical examination and X-ray. Facial appearance and and occlusal relationship were improved greatly. The occlusal plane was almost normal. There was no infection, malunion or permanent injury of inferior alveolar nerve.

[CONCLUSIONS] DO of the ramus is very effective for the correction of severe hemifacial microsomia. It has much better therapeutic effect than traditional orthognathic procedures.