Autotransplantation of teeth is an alternative treatment method in growing patients with hypodontia or impacted teeth. The purpose of the present study was to investigate the occurrence of, and predictors for, the loss of transplanted teeth in children and young adults.

All patients who had undergone tooth transplantation at the Department of Oral and Maxillofacial Surgery, Turku University Hospital, from October 1, 2009 to January 5, 2017, were identified from the hospital's database. The outcome variable was survival of the transplanted tooth. The predictor variables were the transplantation type, donor tooth, maturity of the donor tooth, number of roots of the donor tooth, recipient's jaw, the need for extraoral storage of the donor tooth during surgery, continuation of root development during follow-up, and institution experience. One tooth was randomly selected from each subject. The Kaplan-Meier method for survival analysis, and the Cox proportional hazards regression analysis results were used to assess the association between survival and the risk factors.

The sample included 36 subjects with a mean age of 14.3 years; 33.3% were male, 45 teeth were transplanted, and the median follow-up time was 1.3 years. The 1-year survival rate was 87% (95% confidence interval [CI], 75 to 99%). A significant predictor for tooth survival was the continuation of root development (hazard ratio, 21.3; 95% CI, 2.1 to 215.0; P = .009). Although not statistically significantly, more favorable prognoses were found for distant than for transalveolar transplantations, 1-rooted than multirooted teeth, premolars than molars, teeth not stored in an extraoral media, and teeth that had been transplanted later during the study period.

The experience of the professional team, use of open apex premolars, and postoperative continuation of root development of the transplant were the factors associated with favorable outcomes. Transplants could benefit from the use of 3-dimensional models during surgery.