Surgery-first orthognathic approach for treating malocclusion of patient with hemifacial hyperplasia

Hemifacial hyperplasia (HFH) is a rare congenital condition characterized by significant vertical and horizontal asymmetry of the maxilla and mandible, often resulting in severe skeletal malocclusion. Orthognathic surgery is frequently required to address these skeletal discrepancies. We report the case of a 24-year-old female patient with HFH, presenting with macrodontia and hyperplasia of the left maxilla and mandible, accompanied by severe scissor bite on the affected side. Surgical treatment included zygomatic osteotomy, orbital osteotomy, alveolar segmental osteotomy, left mandibular inferior border ostectomy, and reduction ostectomy of the hypertrophied left mandibular condyle. Postoperative orthodontic treatment was performed, including extraction of the left maxillary first premolar on the affected side. This surgical first multidisciplinary approach successfully improved facial asymmetry and established a functional occlusion. Given the rarity of HFH, long-term outcomes of treatment are seldom reported. In this case, both esthetic and functional occlusion, as well as facial symmetry, were stably maintained for two years post-treatment.