Maxillary Canine Impaction Occurrence and Severity in Relation with Dimensions and Morphology of Sella Turcica: A Retrospective Observational CBCT Study

Objective: To investigate dimensions and morphological characteristics of Sella Turcica (ST) in patients with impacted maxillary canines (IMC), compared to a control group of patients with normally erupted canines, using CBCT images. A secondary aim was to investigate the relationship between the impaction severity and ST parameters. Methods: This retrospective study analyzed CBCT images from 100 patients. The study group included 55 subjects with IMC (n=38 unilateral, U-IMC; n=17 bilateral, B-IMC) and the control group included 45 subjects exhibiting normally erupted canines. ST parameters included linear dimensions (length, depth, diameter), morphological categorization and bridging types. IMC parameters were canine’s three-dimensional positional angles according to Frankfort Horizontal Plane (FHP) and midsagittal plane (MP). Statistical analyses were conducted using two-sample t-test, Man-Whitney U, and One-Way ANOVA tests. Statistical significance was set at 5%. Results: U-IMC-R and B-IMC exhibited significantly higher FHP-RC-Frontal (p<0.001) and MP-RC (p=0.002) angles, but a lower FHP-RC-Lateral angle (p<0.001) compared to U-IMC-L and control groups. Moreover, U-IMC-L and B-IMC groups exhibited significantly higher FHP-LC-Frontal (p<0.001) and MP-LC (p<0.001) angles, but a lower FHP-LC-Lateral angle (p=0.003) compared to U-IMC-R and control groups. There was a significant inverse relationship of 25.5% between ST length and FHP-LC-Lateral angle (p=0.011). Conclusion: IMC was linked with increased FHP-C-Frontal and MP-C angles, but with a decreased FHP-C-Lateral angles. A significant 25.5% inverse relationship between ST length and FHP-LC-Lateral angle was observed. Besides, IMC occurrence and its three-dimensional position did not exhibit correlation with ST's dimensions or morphology.