Mandibular condylar hypoplasia is facial deformity caused by a short mandibular ramus.
(See also Overview of Temporomandibular Disorders.)
This condition usually results from trauma, infection, or irradiation occurring during the growth period but may be idiopathic. The deformity involves fullness of the face on the side on which the ramus is shorter, deviation of the chin toward the affected side, an elongated mandible, and flat appearance of the face on the unaffected side due to stretching of the muscles. Mandibular deviation causes malocclusion.
Diagnosis of Mandibular Condylar Hypoplasia
Imaging (panoramic radiographs)
Diagnosis is based on a history of progressive facial asymmetry during the growth period and radiographic evidence of condylar deformity and antegonial notching (a depression in the inferior border of the mandible just anterior to the angle of the mandible). There is frequently a causative history.
Treatment of Mandibular Condylar Hypoplasia
Surgical management
Treatment consists of osteotomy of the unaffected side of the mandible or surgical distraction (lengthening) of the affected side. Presurgical orthodontic therapy helps optimize results (1).
Treatment reference
1. Yamada H, Sawada M, Tanaka E. Treatment of hemifacial microsomia using conventional orthodontic techniques: Report of a case with long-term follow-up. J Am Dent Assoc. 2021;152(8):653-668. doi:10.1016/j.adaj.2020.10.015
