Sella turcica dimensions in patients with severe skeletal malocclusion using cone-beam computed tomography: a retrospective observational study

Abstract Background As traditional two-dimensional cephalometric analyses of skeletal malocclusions often fail to capture complex craniofacial variations. Recent advances in three-dimensional (3D) imaging have highlighted the correlation between sella turcica morphology and skeletal dysmorphology. This study aimed to explore sella turcica dimensions associated with severe skeletal malocclusion using cone-beam computed tomography (CBCT) to explore other imaging features for such patients. Methods A total of 240 patients were divided into six groups: normal, skeletal Class III, skeletal Class II, open bite, mandibular deviation, and hypodontia. The sella turcica was reconstructed three-dimensionally from CBCT images using Mimic software, and 13 sella turcica dimensions were measured. Additional cephalometric measurements were performed. For intergroup comparisons of sella turcica dimensions, one-way ANOVA, Kruskal-Wallis test, or Welch’s ANOVA was applied depending on Shapiro-Wilk test and Levene’s test. The post-hoc multiple comparisons between the study groups and the normal group were conducted using Dunnett’s test, the Bonferroni correction, or the Games-Howell test, corresponding to the primary analysis method used. Differences between genders were analyzed using the independent samples t-test or the Mann-Whitney U test, as appropriate. The Pearson’s or Spearman’s correlation tests to assess the relationships between sella turcica dimensions and cephalometric measurements. The prevalence of sella turcica bridging (STB) was compared among groups using the chi-square test. Results Sex-based differences were observed in sella turcica dimensions among patients with severe skeletal malocclusion, and females showed significantly lower anterior clinoid distance (ACD), higher sella diameter (SDi) and sella depth (SDe) than males. The mandibular deviation group had a significantly lower dorsum sellae height (DSH) and SDe. The hypodontia group had a lower anterior clinoid distance (ACD) and left sella length (LSL). Notably, female patients with hypodontia demonstrated a more reduction in ACD. No significant differences or strong effect sizes were found for the other sella turcica dimensions among the remaining groups. Significant correlations were identified between sella turcica dimensions (ACD, LSL, posterior right clinoid height [PRCH], DSH and sella length [SL]) and cephalometric measurements (∠Ba-S-N, ∠ANB, ∠NA-PA, pogonion deviation distance [PDD]). STB prevalence was higher in the hypodontia group. Conclusions Distinct morphological patterns were associated with specific malocclusion types. The imaging characteristics of the sella turcica may serve as potential exploratory morphological reference for these patients, particularly in mandibular deviation and hypodontia.