Association between sella turcica bridging and impacted maxillary canines

Changes in sella turcica (ST) development may be associated with impaction of the permanent canine teeth. Calcification of the interclinoid ligament, which forms a bridge between the anterior and posterior clinoid processes of the sphenoid bone, has been termed ST bridging. The aim of this study was to evaluate whether an association exists between ST bridging and the presence of impacted maxillary canines (IMCs) in a Brazilian population. In this case-control study, 2 blinded and calibrated examiners measured the length (interclinoidal distance), depth, and diameter of the ST on cephalometric radiographs of 64 adults divided into a case group with IMCs (n = 32) and a control group without IMCs (n = 32). The degree of calcification was established as no (class I), partial (class II), or complete (class III) calcification. A t test was used to compare ST dimensions between the groups, and a chi-square test was used to analyze the association between the degree of calcification and the groups. The association between ST bridging and IMC was estimated by means of logistic regression analysis (α = 0.05). The study findings showed that ST length in the case group was shorter than that in the control group (P = 0.042; t test), and the length was shorter in men than in women (P = 0.038; t test). The ST bridging frequency was higher in the case group (P = 0.03; chi-square test), and there was no difference between men and women. The presence of ST bridging might be associated with increased odds of IMCs (P < 0.01; adjusted odds ratio = 5.92). In this patient sample, the occurrence of IMCs was positively associated with the presence and severity of ST bridging.