Pre‐treatment radiographic features predict root resorption of treated impacted maxillary central incisors

OBJECTIVES: To determine independent predictors of root resorption for 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. Root resorption and its predictors were abstracted from patients' charts, pre-treatment cephalometric radiographs, and post-treatment periapical radiographs. Predictors included demographics, treatment duration, crown angle, crown height, crown depth, and root dilacerations. RESULTS: The patients' mean age was 9.2 ± 2.3 years (6.4-20.6 years), and 60% were females. Impacted maxillary central incisors had greater root resorption than naturally erupted contralateral incisors (Δ = -2.8 mm, p < 0.001). Independent predictors of root resorption for impacted maxillary central incisors were shown by linear regression analysis to be crown height (β = -0.2, p < 0.01), crown depth (β = -0.3, p = 0.001), treatment duration (β = 0.2, p < 0.01), and root dilacerations (β = 3.1, p = 0.001). CONCLUSIONS: Impacted maxillary central incisors had greater root resorption during surgical-orthodontic treatment than their naturally erupted contralateral incisors. Predictors of a greater root resorption were highly and deeply impacted incisors, longer treatment, and root dilacerations. These predictors may help to inform patient and family counseling before treatment.