Association between the three dimensional index and panoramic angular parameters (α and θ angles) in impacted maxillary canines

Introduction: Impacted maxillary canines are among the most common orthodontic anomalies and often require comprehensive radiographic assessment for accurate diagnosis and treatment planning. The KPG index is a CBCT-based three-dimensional classification system used to evaluate the severity of canine impaction. Aim: To assess the association between the KPG index and angular parameters (α and θ angles) in impacted maxillary canines. Materials and Methods: This retrospective study included 30 patients with impacted maxillary canines treated at the Department and Clinic of Orthodontics, Faculty of Dental Medicine, University of Sarajevo. Cone-beam computed tomography (CBCT) scans and panoramic radiographs were analyzed. The KPG index was determined from CBCT images, while α and θ angles were measured on panoramic radiographs. Correlation analysis was performed to evaluate the relationship between the KPG index and angular parameters. Results: The mean KPG index was 13.17 ± 7.29, the mean α angle was 32.93 ± 21.34°, and the mean θ angle was 53.87 ± 19.91°. A statistically significant moderate positive correlation was found between the KPG index and α angle (rs = 0.635, p < 0.001). No statistically significant association was observed between the KPG index and θ angle (rs = −0.234, p = 0.206). Conclusion: The α angle showed a significant positive association with the KPG index and may represent a useful adjunctive parameter in the assessment of impacted maxillary canines. In contrast, the θ angle was not significantly associated with impaction severity. Although panoramic radiographs provide valuable diagnostic information, CBCT-based three-dimensional imaging remains the gold standard for evaluating impacted maxillary canines and supporting orthodontic treatment planning.