Relationship between palatal canine impaction and sella turcica bridging

Introduction: After the third molars, the maxillary canines are the most frequently impacted teeth. Sella turcica bridging (STB) can be used as a predictive factor to help orthodontists in early diagnosis. The aim of this study was to investigate the relationship between palatal canine impaction (PCI) and STB. Materials & Methods: In this case-control study, in available lateral cephalograms and panoramic radiographs of 53 patients with PCI and 53 controls with normal dentition and no impacted canines the dimensions of STB were measured and graded. Grade I (no calcification): The length of the sella is greater than ¾ of its diameter.Grade II (partial calcification): The length of the sella is equal to or less than ¾ of its diameter.Grade III (complete calcification): A separation bridge is clearly visible on the radiograph. The patients and controls were between 12 and 20 years of age. The relationship between STB and PCI was analyzed using the Chi-square test, Mann-Whitney test, and Fisher’s exact test. A value of P<0.05 was considered significant. Results: There was a significant relationship between STB and PCI (P<0.001). A significant relationship was also found between STB severity grade and PCI (P<0.001). The probability of the presence of Grade II STB in patients with PCI was three times higher than in those with normal dentition. The probability of the presence of Grade III STB in patients with PCI was approximately 46 times higher than in individuals with normal dentition. The length: diameter ratio of the sella turcica was not significantly different between the two groups of patients and controls. No significant relationship was found between gender and STB.  Conclusion: The relationship between STB and PCI could be used as diagnostic early indicator to confirm PCI.