Prevalence and dimensions of sella turcica bridging in Japanese female orthodontic patients

Purposes The purposes of this study were to examine the prevalence of sella turcica bridging; to evaluate age-related differences in sella turcica dimensions and the prevalence of sella turcica bridging; and to clarify the associations of sella turcica dimensions and bridging with maxillofacial skeletal patterns and dental anomalies, such as tooth agenesis and impaction, in Japanese female orthodontic patients. Materials and methods Lateral cephalograms and panoramic radiographs of 232 Japanese female orthodontic patients, aged 7–35 years, were examined. In addition to conventional cephalometric measurements, sella turcica diameter (STD), interclinoid distance (ICD), and degree of ICL calcification [(STD ICD) to STD ratio] were evaluated. Results Sella turcica bridging occurred in 5.6% of all subjects. The mean values of STD, ICD, and degree of ICL calcification were 9.8 mm, 3.9 mm, and 60.0%, respectively. STD and degree of ICL calcification were larger and ICD was smaller in the ≥19-year-old group than in the 7–12-year-old group. No significant difference in sella turcica dimension or bridging prevalence was found in the anteroposterior or vertical skeletal pattern. Subjects with tooth impaction showed shorter ICDs and greater degrees of ICL calcification than did those without tooth impaction. Conclusions The prevalence of sella turcica bridging was 5.6%, and STD, ICD and degree of ICL calcification increased with age, in Japanese female orthodontic patients. In addition, sella turcica morphology and bridging were associated with tooth impaction, but not with maxillofacial skeletal deviations.