Orthodontics First in Hemimandibular Hyperplasia. "Mind the Gap".

A 32-year-old man was referred to the Division of Orthodontics of the University of Naples "Federico II", with a 15-year history of gradually increasing right-sided facial asymmetry. Clinical and radiological examinations was consistent to hemimandibular hyperplasia, a rare developmental asymmetry characterized by three-dimensional enlargement of one-half of the mandible. The standard surgical-orthodontic management was proposed to the patient. However, he refused to undergo bimaxillary orthognatic surgery. Therefore, a different treatment was proposed based on the orthodontic technique of pre-surgical decompensation and post-surgical refinement used in bimaxillary orthognatic surgery planning, and surgical intervention with a condylectomy. The dental arches were evenly levelled out with a multi-bracket treatment and then the condylectomy was performed. Orthodontic treatment continued with a levelling and torque control by 0.19 × 0.25 SS arch and physiotherapy. At the three-month follow-up, the patient showed anterior and posterior bite rebalancing, arch intercuspation recovery, and anterior open bite closure due to muscular self-rebalancing. The two-year follow-up showed regular mandibular dynamic, orthodontic appliances were removed, and the patient was instructed to wear retainer for the following months. The final result was aesthetically reasonable for the patient, although slight asymmetry of the chin persisted.