Three-Dimensional Volumetric Evaluation of the Sella Turcica and Sphenoid Sinus in Individuals with Unilateral...

Background/Objectives: The sella turcica and sphenoid sinus are anatomically adjacent structures within the cranial base and may reflect variations related to craniofacial development. However, evidence regarding their three-dimensional characteristics in individuals with impacted canines remains limited. This study aimed to evaluate the morphological, linear, and volumetric characteristics of the sella turcica and sphenoid sinus in individuals with unilateral palatally impacted maxillary canines using cone-beam computed tomography (CBCT). Methods: This study included CBCT scans of individuals with unilateral palatally impacted maxillary canines and a control group. Linear measurements and morphology of the sella turcica were assessed. Sella turcica volume was calculated using both a geometric formula and voxel-based three-dimensional segmentation. Sphenoid sinus pneumatization patterns and volumes were also evaluated. Agreement between volumetric measurement methods was assessed using Bland-Altman analysis, and correlations between sella turcica and sphenoid sinus volumes were also analyzed. Results: Most morphological and volumetric parameters of the sella turcica and sphenoid sinus were comparable between groups. Among the linear measurements, only sella width was significantly greater in the control group, whereas other dimensions showed no significant differences. The distribution of sella turcica morphology and sphenoid sinus pneumatization patterns was similar in both groups. No significant differences were observed in sella turcica or sphenoid sinus volumes. Bland-Altman analysis demonstrated good agreement between geometric and voxel-based volumetric measurements. In addition, no significant correlation was identified between sella turcica and sphenoid sinus volumes. Conclusions: Unilateral palatally impacted maxillary canines were not associated with substantial morphological or volumetric alterations of the sella turcica or sphenoid sinus. These findings suggest that variations in these cranial base structures have limited value as indicators of unilateral palatal canine impaction.