Autotransplantation Using An Adult Immature Third Molar: A Case Report

Tooth autotransplantation offers a biological alternative therapy for tooth to be extracted. Periodontal healing of immature transplanted tooth is predictable, however, positive responses to electric pulp testing (EPT) are less consistent. A maxillary right first molar of a 24-year-old woman was extracted due to severe caries one year ago. Tooth autotransplantation was a part of orthodontic treatment plan. Preoperative CBCT images reveal an impacted maxillary third molar with a single root and a 2-mm open apex. A 3D-printed replica of the donor tooth was fabricated for guiding socket preparation. Minimally invasive extraction of tooth 28 was followed by immediate transplantation to site 16. Subsequently, the transplanted tooth with neighboring teeth was stabilized with a buccal resin-wire splint for four weeks. Three months later, the patient underwent fixed orthodontic treatment using light orthodontic force. Dental radiographs taken at 1, 3, 6, 12, 18 months showed normal periodontal ligament space, continuous development of root apex and progressive pulp and root canal obliteration. At 18 months, the transplanted tooth garnered EPT response. Prophylactic root canal therapy (RCT) is recommended for mature donor teeth. Immature donor teeth usually regain EPT response within 6-12 months, but the EPT response could be late as 18 months. The RCT should be cautiously performed if apical periodontitis of immature donor tooth does not occur. Close postoperative monitoring is a viable approach for immature transplanted tooth using clinical signs, symptoms and dental radiographs, preserving pulp healing potential and avoiding premature endodontic intervention.