Prediction of the success of orthodontic treatment of impacted maxillary canines using panoramic radiography parameters: a retrospective cross-sectional study

Abstract

Background This retrospective study aimed to investigate the relationships between the radiographic features of impacted maxillary canines (IMCs) and traction duration and the factors affecting treatment success. Methods Pre-treatment panoramic radiographs and patient records of 121 consecutive patients with IMCs were analyzed. The measurements included the angle of the IMC with the midline (α-angle), the horizontal position of the IMC relative to the adjacent teeth (S-Sector), the distance from the IMC to the occlusal plane (d-distance), the apex position of the IMC (A), and the vertical height of the IMC relative to the adjacent lateral tooth (V). The measurements were repeated 1 week later. The intraclass correlation coefficient was used to evaluate the relationship between two measurements. Binary logistic regression was performed to determine the factors affecting treatment success. Linear regression was conducted to determine the relationships between traction duration and other parameters. Receiver operating characteristic (ROC) curve analysis was performed to determine the α-angle and the d-distance cutoff values for treatment success. The significance level was set at p < 0.05. Results The buccally IMCs were mostly located in sectors 1–2, whereas the palatally IMCs were mostly located in sectors 3-4-5. The effects of the parameters on the treatment success were significant according to the logistic regression of age (p = 0.003), d-distance (p = 0.002), and α-angle (p = 0.001). Linear regression analysis revealed that traction duration was statistically significant (p < 0.001). Conclusion According to the results of this retrospective study, the α-angle, d-distance, and sector can be used to predict the buccopalatal position of the IMC. The patient’s age, d-distance, and α-angle affected the treatment success. The patient’s age, d-distance, and the sector of the impacted canine affected the traction duration. Clinical trial number Not applicable.