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Introduction The aim of this study was to determine the incidence of bridging of the sella turcica and the dimensions of the Sella in subjects with dental anomalies (transpositions, hypodontia, and supernumerary teeth) and to compare them to controls. Methodology Lateral cephalograms from 25 patients with dental transposition, 88 with hypodontia, and 26 with supernumerary teeth were evaluated. The shape, length, depth, diameter, and bridging of the Sella turcica were determined from radiographs and compared to those of control group (n=52). For statistical analysis, one-way ANOVA, Tukey post-hoc test, chi-squared test and T-test (to evaluate the influence of craniofacial growth) were used. Results The frequency of complete calcification of the Sella was greater in the group with supernumerary teeth (23%) and in the group with hypodontia (14.7%), while partial calcification of the Sella was more frequent in the control group (77%) and in the group with supernumerary teeth (73%)(p<0.05). The depth of the Sella was greater in the group with dental transposition. Oval and round Sella shapes were more frequent in all groups, and a flat Sella was rarely seen. In terms of the influence of growth on the dimensions of the Sella, there was no statistically significant difference between pre- and post-treatment radiographs. Conclusion Significant relationships were found between dental anomalies and bridging and shape of the Sella. The Sella was also significantly deeper in patients with dental transposition. The bridging and shape of the Sella may be useful in the diagnosis of dental anomalies in early childhood.

Skeletal changes following surgically assisted rapid maxillary expansion (SARME)Purpose Surgically assisted rapid maxillary expansion (SARME) is a common treatment technique in the correction of maxillary transverse deficiency. The purpose of this study was to evaluate nasal and palatal skeletal changes following SARME using Cone Beam Computed Tomography (CBCT) and posterior anterior (PA) cephalograms. Materials and MethodsIn this retrospective study, the radiographic images obtained from 14 patients with transverse maxillary deficiency before treatment and 6 months after SARME operations were evaluated. The changes in nasal bone width and palatal bone width were measured on CBCT. The changes in basal maxillary width, nasal cavity width and angular measurements were evaluated on PA cephalograms. ResultsNasal floor width was measured at the levels of upper first premolar teeth and molar teeth which significantly increased following SARME (p=0.005 and 0.017 respectively). Palatal bone width between first premolar teeth and molar teeth also significantly increased (p=0.003 and 0.002 respectively). Basal maxillary width (p=0.026), nasal cavity width (p=0.024) and other angular measurements also significantly increased (p<0.05). ConclusionNasal and palatal skeletal transverse dimensions increased following SARME. Due to the enlargement of the nasal floor and nasal cavity, it is likely to improve air pass through the nose.

Objective: This study evaluated the stress distribution and displacement on impacted maxillary canines and their adjacent teeth of orthodontic forced eruption using Ballista and Kilroy springs by finite element model (FEM) analysis. Methods: Two different FEMs applying the same force level on an impacted canine tooth (Model 1: Ballista spring, Model 2: Kilroy spring) were conducted using FEM analysis and the principal stresses, von Mises stresses, and displacements were evaluated. Results: Von Mises values at the cusp tip of impacted canines were measured as 0.009896 N/mm² in the Ballista model and 0.015334 N/mm² in the Kilroy model. The highest value was measured in the buccal apex of the first premolar in both spring designs. The extrusion was observed in Ballista, and intrusion was observed in the Kilroy model at the apex of the first premolar. The Ballista model showed the highest value (0.003642 N/mm²) at the buccal tip of the first premolar, while in the Kilroy model, the highest measurement (0.002989 N/mm²) was shown at the incisal edge of the lateral tooth. Conclusion: Von Mises stress values were higher in the Kilroy model at the cusp tip and apical part of the impacted tooth than that in the Ballista model. The highest von Mises stress values were concentrated on the buccal root apex of the first premolar in both models. Although the amount of force applied by the springs was the same, the stress values were different depending on the spring design.