Variants of the position of the first permanent molars relative to the pterygoid vertical plane on a lateral teleradiography

Determination of the position of key teeth in the gnathic part of the facial region of the head according to teleradiography data is an urgent task of clinical orthodontics. Purpose. To determine the variants of the position of the first permanent molars relative to the pterygoid vertical plane on the lateral teleradiograph and to develop a model for predicting the optimal position of key teeth in the structure of the gnatic part of the face. Material and methods. The analysis of 48 teleradiographs of young people with occlusion physiology and 23 teleradiographs of children in different periods of removable occlusion was carried out. The analysis used the Ralph E. McDonald method and the developed original mole for predicting the optimal position of the occlusion keys. Results and discussion. The analysis of teleradiographs revealed that the distance from the pterygoid vertical plane PTV to the distal surface of the upper first permanent molar in the group as a whole was (18.37 ± 3.62) mm. The average distance between the articular and spinal verticals in the analyzed group was (89.12 ± 2.8) mm. At the same time, the sagittal size averaged (58.74 ± 1.57) mm, and the anterior size was (30.41 ± 1.02) mm. A relatively stable indicator was the ratio of the sagittal size of the gnathic complex to the posterior part, which averaged 1.5 ± 0.06. Conclusion. In the course of the analysis, an optimal model for predicting the first permanent molars was developed, which is an objective method of analysis in different periods of ontogenesis, regardless of the sagittal size of the gnatic calving of the face. The ratio of the condyllospinal size to the coefficient of 1.5 determines the position of the medial surface of the first molar, which can be used in the orthodontics clinic to diagnose anomalies in the position of teeth and dental arches.