Abstract
In the case of hypoplasia of a unilateral temporomandibular joint, the mandible has a tendency to deviate into the affected side as a result of asymmetric mandibular growth. Therefore, in cases with mandibular micrognathia and facial asymmetry with hypoplasia of the temporomandibular joint, surgical procedures have been performed to improve the function and morphology of the mandible. In the present case, a costochondral graft was performed on a Goldenhar syndrome patient with mandibular micrognathia and mandibular deformity of the left side. The present case report describes the reconstruction of the mandibular ramus on the left side using a costochondral junction and its treatment progress. A 4-year-11-month-old girl, introduced by the Department of Plastic and Reconstructive Surgery of Shinshu University School of Medicine, visited the clinical orthodontic department of Matsumoto Dental University Hospital for occlusal management. She showed a convex profile with mandibular retrognathia, severe deviation of the mandible to the left side on the frontal view, and anterior openbite （overjet: ＋6.0mm, overbite: −2.0mm）. A lateral cephalometric analysis indicated mandibular retrognathia （SNA：77.0°，SNB：62.5°，ANB：＋14.5°）. At 6 years and 3 months old, she had started using a hybrid FKO, to manage the occlusal relationship and growth direction of the mandible. At 8 years and 11 months old, grafting of the costochondral junction was performed on the left side for reconstruction of the mandibular ramus. Four years and 10 months after the costochondral graft （when 13 years and 9 months old）, the growth of the grafted costochondral junction was confirmed. Additionally, it had controlled the aggravation of the skeletal discrepancy. Her masticatory function was as stable as before the surgery. In this case, the costochondral graft was performed on the patient with Goldenhar syndrome with mandibular micrognathia and mandibular deformity on the left side. It improved the patient’s chief complaint and masticatory function. In order to support the maxillofacial morphology and masticatory function, reconstruction of the mandibular ramus before the growth spurts of adolescence is beneficial and recommended. Reconstruction of the mandible with hypoplasia using the costochondral junction is a treatment option that is expected to encourage mandibular growth for patients with mandibular micrognathia and facial asymmetry.
