The Relationship Between Vertical Malocclusions and Ossification Changes in the Cranial Base and Upper Cervical Spine [Conference Winner Abstract]

Introduction Skeletal development of the neck and shoulders, sella turcica, and dental epithelial cells share a common embryonic origin [1, 2]. Therefore, skeletal orthodontic anomalies may be associated with anomalies like sella turcica bridging (STB) and ponticulus posticus (PP) [3]. PP is a complete or incomplete osseous bridge between the atlas and axis vertebrae, crossing the vertebral artery groove [4, 5]. STB is a cranial base anomaly, characterized by a concave structure located above the body of the sphenoid bone, surrounded by its anterior and posterior vertical walls [6]. Identifying these structures is important, as they can be observed during routine radiographic evaluations and may be linked to the patient’s overall health. Aim To evaluate the relationship between vertical malocclusions, cervical maturation stages, and the morphological features of STB and PP. Methods The study sample consisted of 300 pre-orthodontic treatment patients (153 females, 147 males) aged 7–40 years, randomly selected from the Department of Orthodontics at the Lithuanian University of Health Sciences. According to the study protocol, cephalometric analysis was performed twice by two researchers. Under the supervision of a radiologist, sella turcica and atlas evaluations were performed using a scoring scale described by Leonardi et al. [7]. Cohen’s Kappa analysis was performed to determine the agreement between both investigators. Based on the SNMP angle, subjects were categorized into groups: low (LA≤28°), normal (28°<NA<36°), and high cranial angle (HA≥36°). Statistical analysis was performed with SPSS 29.0. Results The prevalence of incomplete PP was 40% (29.67% open groove, 11.33% half-open groove), and complete PP was 11.33%, being more common in males (56.7%; p=0.005). STB had a prevalence of 52.67% (15.67% complete, 37.0% partial), with a higher prevalence in females (60.1%; p<0.001). According to cervical maturation stages, PP and STB were more common during the postpubertal period (CS5 and CS6 stages). However, only STB showed a statistically significant difference (p=0.019). Based on vertical skeletal malocclusions, PP and complete STB occurred more frequently in patients with a low cranial base angle (43.3% and 51.1%, respectively). However, it was not statistically significant (p>0.05). According to logistic regression, men were twice more likely to have an open groove of PP (p=0.015), while females had higher odds of partial (OR=2.2) and complete STB (OR=2.4, p<0.05). Conclusions The anatomical characteristics of ponticulus posticus and sella turcica bridging were related to gender. Ponticulus posticus was more common in males, while sella turcica bridging was more common in females. Both anomalies were more frequent in individuals with low cranial base angle and during the postpubertal period, suggesting a possible age-related relationship with abnormal ligament calcification.