A Case of skeletal Class III Open Bite Treated by Orthognathic Surgery with Distraction Osteogenesis

The patient was a 19-year-old male with mandibular prognathism, open bite and a thin symphysis. The chief complaints were difficulty in biting with the anterior teeth and anterior crowding. The problems were: 1) mandibular prognathism; 2) skeletal open bite; 3) a narrow upper dental arch; 4) severe lingual inclination of the lower incisors and a thin symphysis; and 5) crowding. Surgical procedures were utilized to perform orthodontic treatment. Before the orthognathic surgery, crowding and the narrow dental arch were eliminated with orthodontic treatment involving surgically assisted rapid palatal expansion. Segmental osteotomy and gradual distraction osteogenesis of the lower anterior teeth were performed to change the severe lingual inclination of the symphysis. After alignment of the upper and lower dental arches, sagittal split ramus osteotomies were undergone to correct the mandibular prognathism and skeletal open bite. In the post-operative period, detailing and completing teeth alignment were performed, and suitable occlusion was finally achieved. This case shows that changing the inclination of the symphysis by distraction osteogenesis is effective for patients with a thin symphysis.