Association of Sella Turcica Morphology and Taurodontism with Dental and Skeletal Relationships Among Twins in Saudi Arabia

Background: Twin studies comparing craniofacial and dental characteristics in monozygotic and dizygotic twins help to differentiate genetic from environmental influences. This study assessed sella turcica morphology and taurodontism in relation to dental and skeletal relationships among twins in Saudi Arabia. Methods: A cross-sectional study was conducted among 64 twins (15 monozygotic pairs and 17 dizygotic pairs), aged 6–16 years, in Jazan, Saudi Arabia. Sella turcica morphology, size, and bridging were assessed using cephalometric images, while taurodontism was evaluated using panoramic radiographs. Skeletal and dental malocclusions were classified using established orthodontic criteria. Significant statistical analysis of comparisons and associations was set at p < 0.05. Results: No significant differences were observed between monozygotic and dizygotic twins regarding sella turcica size or morphology, skeletal and dental classifications, and first molar taurodontism indices. The sella turcica depth (p = 0.01) and anteroposterior width (p = 0.03) were positively associated with dental class III malocclusion, and sella depth (p = 0.02) was positively associated with age. Mandibular molar taurodontism (tooth #46) was positively associated with dental Class II and Class III malocclusions and negatively associated with age. Maxillary molar taurodontism (tooth #16) showed a significant positive association with dental Class III malocclusion. The sella bridging and sella shape categories showed low within-pair concordance (<55%) and no significant association with skeletal or dental classification (p > 0.20). Conclusions: Zygosity was not significantly associated with sella turcica characteristics, taurodontism, or dental and skeletal relationships in this cohort. However, selected sella turcica dimensions and taurodontism indices were associated with malocclusion patterns and age, warranting further investigation.