Mandibular symphyseal distraction and its geometrical evaluation: report of a case.

In this report, the case of a patient who has been treated with a different use of a tooth-borne custom-made mandibular symphyseal distraction device is presented. The difference in the application is that the distal arm of the device was sectioned during the retention phase to allow the possible relapse of displaced condyles to their original positions while the labial segment expansion is being maintained. The effect of this procedure was also evaluated on a geometrical model using measurements from the patient's cast. We conclude that symphyseal distraction is an effective and fast method of correcting orthodontic anomalies. The effect of the procedure on the condyle was only 3 degrees of distolateral rotation as calculated using the geometrical model.