Main Instructor Hung-Cheng Chiu
Department / Institution National Taiwan University Hospital
Classification Case report
「Case」: This is an 18-year-old healthy female patient who had a convex lateral profile and lip incompetence with the complaint of crooked teeth and dental crowding in the anterior region. Tooth 12 was a peg lateral incisor and tooth 23 was congenital missing with tooth 63 retained. She presented skeletal and dental Class II malocclusion with mandibular retrognathism, severe space deficiency on both arches and large overjet. The patient preferred the non-surgical treatment plan to the surgical treatment. We extracted teeth 12, 63, and used mini-plates and mini-screws for distalization and intrusion to relieve crowding and improve profile. The patient got a satisfactory occlusion and appearance after 2 years of treatment. However, after 3 years of retention, we found overjet increased from 2.5 mm to 4 mm. Relapse resulted from upper molar mesialization and extrusion.
「Discussion & Summary」: We pushed the envelope of distalization in lower arch to avoid extraction of lower arch on retrognathic mandible. During treatment, distal wedge surgery was performed at bilateral retromolar areas. We observed mandible autorotation after upper molars intrusion. Follow-up visit showed mild relapse occurred after 3 years. In summary, temporary anchorage devices enable distalization and intrusion successful. However, the direction and amount of relapse should be carefully monitored.
A Three-year Follow‐up of Distalization and Intrusion with Temporary Anchorage Devices