Morphological types of sella turcica bridging and sella turcica dimensions in relation to palatal canine impaction: a retrospective study

The aim of this study was to determine the relationship between the presence of sella turcica bridging and palatal canine impaction (PCI) using several classification methods. In this retrospective study, lateral cephalometric radiographs of 120 subjects with PCI (43 males, 77 females; mean age 18.8 ± 7.8 years) and 120 controls (44 males, 76 females; mean age 18.1 ± 5.6 years) with complete permanent dentition were examined. The extent of sella turcica bridging was assessed using two different methods, and the types of complete sella turcica bridging were evaluated. The sella turcica dimensions were measured and analyzed using the t-test, and comparison of the presence of sella turcica bridging was performed using the two-tailed Fisher’s exact test. The frequency of complete sella turcica bridging was significantly higher in subjects with PCI (18.3%) than in controls (8.3%, p = 0.023) but without significant differences in the occurrence of sella turcica bridging of Type A (ribbon-like fusion) and Type B (extension of clinoid processes). No significant differences in partial bridging were found between patients with PCI and controls according to both methods. The length and the anteroposterior diameter were significantly larger in subjects with PCI and no difference was observed between the groups in the sella turcica depth. Complete sella turcica bridging occurred significantly more frequently in subjects with PCI than in controls. However, the association between partial bridging and PCI was not confirmed, therefore, we do not recommend any classification of partial bridging for clinical practice.