Simultaneous Arthroplasty and Two-jaw Surgery for Treatment of a Case with Facial Asymmetry by Hemimandibular Hyperplasia

Facial asymmetry is known to have various causes, one of which is hemimandibular hyperplasia. This condition causes malocclusion as well as facial asymmetry. Here, we describe the combined surgery and orthodontic treatment performed for a patient with facial asymmetry accompanied by inclination of the maxillary occlusal plane as a result of mandibular asymmetry caused by hemimandibular hyperplasia. Based on the progress of bone scintigraphy, it was determined that accumulation in the mandible was ongoing and that condylectomy was required. Preoperative simulations conducted with the attending surgeon did not produce satisfactory occlusion with condylectomy alone, and it was therefore decided to simultaneously carry out maxillary and mandibular repositioning. Consequently, favorable occlusion was obtained during dynamic orthodontic treatment, and the facial features were improved. Furthermore, a satisfactory occlusal status was observed two years after the completion of dynamic orthodontic treatment.