Predictors of surgical-orthodontic treatment duration of unilateral impacted maxillary central incisors

To determine independent predictors of duration of surgical-orthodontic treatment of impacted maxillary central incisors. Setting and Sample Population- The Department of Dentistry at Show Chwan Hospital, Changhua, Taiwan. Eighty patients with unilateral osseous impacted maxillary central incisors receiving a surgical-orthodontic treatment. Material and Methods- This is a retrospective observational study. Treatment duration and its predictors were abstracted from the patients' charts and pre-treatment cephalometric radiographs. Predictors included demographics, crown angle, crown height, crown depth, and root dilacerations. Results- The mean age of the cohort was 9.2±2.3years (6.4-20.6years), and 60% were women. The mean orthodontic traction time was 8.0±4.5months (2.0-24.1months). Using multiple linear regression analysis, the independent predictors of treatment duration for an impacted maxillary central incisor were age (β=0.9, p<0.001), crown height (β=-0.2, p<0.05), and root dilacerations (β=3.8, p<0.001). Conclusions- Duration of surgical-orthodontic treatment of an impacted maxillary central incisor varied widely. Predictors of longer treatment time were older age, high impacted tooth, and dilacerated incisors.