Radiographic Prediction of Surgical Difficulty in Impacted Canines Using CBCT

Abstract

Background:

Impacted maxillary canines are among the most common impacted teeth and often present considerable surgical challenges because of their variable three-dimensional position and close relationship with adjacent teeth and surrounding anatomical structures. Conventional two-dimensional radiographic techniques provide limited information regarding the exact position of impacted canines. Cone-beam computed tomography (CBCT) offers detailed three-dimensional imaging, enabling comprehensive preoperative assessment and facilitating prediction of surgical difficulty.

Aim:

To evaluate the ability of CBCT-derived radiographic parameters to predict the surgical difficulty of impacted permanent maxillary canine management.

Materials & Methods:

 A retrospective observational study was conducted on CBCT images of 80 patients with impacted permanent maxillary canines requiring surgical exposure or extraction. Radiographic parameters assessed included the location of impaction, vertical position, distance from the occlusal plane, root morphology, contact with adjacent roots, external root resorption, cortical bone thickness, and follicular space width. Surgical difficulty was categorized as mild, moderate, or severe using a standardized intraoperative scoring system based on operative time, extent of bone removal, need for tooth sectioning, and intraoperative complications. Statistical analysis was performed using descriptive statistics, Chi-square test, one-way analysis of variance (ANOVA), multivariate logistic regression, and receiver operating characteristic (ROC) curve analysis. A p-value <0.05 was considered statistically significant.

Results:

Among the 80 impacted canines, palatal impaction (61.3%) was more common than buccal impaction (38.7%), and moderate surgical difficulty was the most frequently observed category (45.0%). Cortical bone thickness, operative time, distance from the occlusal plane, and follicular space width increased significantly with increasing surgical difficulty (p <0.001). Multivariate logistic regression identified impaction depth (OR=3.82, p<0.001), cortical bone thickness (OR=4.16, p<0.001), palatal position (OR=2.71, p=0.009), and root dilaceration (OR=2.43, p=0.028) as independent predictors of increased surgical difficulty. ROC analysis demonstrated that the combined prediction model had the highest diagnostic performance area under the ROC curve (AUC=0.892, sensitivity=86.5%, specificity=82.4%), outperforming individual predictors such as impaction depth (AUC=0.842) and cortical bone thickness (AUC=0.815).

Conclusion:

CBCT provides valuable three-dimensional anatomical information for predicting the surgical difficulty of impacted maxillary canine management. Greater impaction depth, increased cortical bone thickness, palatal position, and root dilaceration were identified as significant predictors of surgical complexity. Preoperative recognition of these radiographic features can improve surgical planning, facilitate risk assessment, reduce intraoperative complications, and contribute to better treatment outcomes.