Surgical orthodontic correction of Class II open bite with idiopathic condylar resorption

The correction of severe mandibular retrognathia associated with idiopathic condylar resorption (ICR) is one of the most difficult challenges in orthodontics. This article reports on the treatment of an adult patient with severe mandibular retrognathia associated with ICR treated with orthognathic surgery. A female patient aged 18 years and 8 months presented with a complaint of maxillary protrusion and retropositioned chin. Her overjet and overbite were 6.0 mm and −2.5 mm, respectively. She had a history of orthodontic treatment in which her maxillary and mandibular first premolars were extracted. She was diagnosed with mandibular retrognathia involving the ICR with a skeletal Class II jaw-base relationship and a high mandibular plane angle. After 13 months of preoperative orthodontic treatment, Le Fort I osteotomy and bilateral sagittal split ramus osteotomy were performed. In addition, the genioplasty was performed after 6 months of postoperative orthodontic treatment. After 27 months of active orthodontic treatment, the retropositioned chin was improved, and an acceptable occlusion with a Class I molar relationship and a proper interincisal relationship were achieved. After the 1-year retention period, an acceptable and functional occlusion was maintained without a significant recurrence of mandibular retrognathia. The results indicate stability after orthognathic surgery in a patient with mandibular retrognathia involved in ICR when surgical mandibular advancement is performed with sufficient consideration.