Orthodontic treatment including autotransplantation of a mature tooth

The patient was a 24-year-old Japanese female. The chief complaints were crowding and masticatory dysfunction due to the missing right first molar. Her maxillary first premolars had been extracted when she was a primary school student. We planned orthodontic treatment with extraction of the mandibular first premolars and transplantation of the mandibular left first premolar into the maxillary right first molar area. We made a diagnostic setup model to initiate an appropriate treatment plan for the discrepancy in tooth size ratio. Following the diagnostic setup model, the space in the maxillary right first molar area was closed by a small amount of tooth movement, and a good occlusion was achieved. The patient had been in retention for 7 years, and the occlusion has been maintained very well during this time. In the follow-up, 10 years after autotransplantation, no signs of inflammatory or replacement root resorption were found, and marginal bone support appeared similar to that of neighboring teeth.