A case report of congenital aglossia.

A case of congenital aglossia was orthodontically treated and long-term retention was observed from the age of 15 to 27. The patient had congenital absence of three lower incisors, abnormally small mandible (micrognathia), severe overbite and a telescopic bite in the premolar region accompanied by an extremely narrow lower arch. Orthodontic treatment was begun when the patient was 15 years and 6 months old. The active treatment period was 2 years and 9 months. At the present time, nine years have passed since the end of the active treatment, and intercuspation between the upper and lower arches is still good. It is suggested that the maintenance of the lower arch width is essential for long-term retention in cases of congenital aglossia.