Regression models of teleradiographic indicators of the position of teeth and the profile of face soft tissues in ukrainian young men and young women with different face profiles according to Schwarz A. M.
Authors: Prokopenko O. S. 
Published: September 2021

Annotation. The needs of modern dentistry require constant improvement of research methods of human dental apparatus, parameters of craniofacial structures, determination of congenital and acquired deformities of the dental apparatus and improving the consequences of treatment. Diagnosis of orthodontic pathology is based on the identification of a large number of different indicators, which requires the use of mathematical analysis not only to processing of received parameters, but also to mathematical modelling individual cephalometric, gnatometric indicators, facial soft tissue parameters that affect its profile and aesthetics. The aim of the work is to develop and analyze regression models of teleradiographic indicators of tooth position and facial soft tissue profile indices according to A. M. Schwarz in Ukrainian boys and girls with orthognathic occlusion and with different facial profiles. Lateral teleroentgenograms (TRG) of 49 young men aged 17 to 21 years and 76 young women aged 16 to 20 years with a physiological bite as close as possible to orthognathic were analyzed. In the licensed package “Statistica 6.0” regression models of teeth position and soft tissue profile according to the A. M. Schwarz method are built depending on the basic cephalometric (1st group) and gnatometric (2nd group) indicators separately for young men and young women with different facial profiles according to A. M. Schwarz In young men, 21 of the 24 possible reliable regression models with coefficients of determination greater than 0.6 (R2 = from 0.736 to 0.999) were constructed. For young men with 2 face profile (straight face profile), the following models of all 8 indicators were built, and the coefficients of determination in the models of this group of persons (R2 = from 0.966 to 0.999) were the highest compared to the models of other groups of young men or young women. For young men with 3 face profile (front face profile), models were built for 7 indicators (except for the SnPog'-Pn angle indicator) with R2 from 0.736 to 0.983. For young men with 1 face profile (back face profile), such models were created for 6 indicators (R2 from 0.815 to 0.993) – in addition to the angle II and the angle SnPog'-Pn. A total of 18 models out of 24 possible were built for young women (R2 = from 0.736 to 0.999). In young women with 2 face profile, as well as in young men with this profile, models were constructed for all 8 studied TRG-indicators of tooth position and facial soft tissue indicators according to A.M. Schwarz (R2 = from 0.736 to 0.982), and for young women with 3 face profile – for 7 indicators (except for angle II) with R2 from 0.604 to 0.740. For young women with 1 face profile, the smallest number of models of the studied indicators was constructed in comparison with all groups of young men or young women with different face profiles – only 3 models out of 8 possible: for Sn-Pn distance (R2 = 0.828), Pog'-Por distance (R2 = 0.844) and the angle SnPog'-Pn (R2 = 0.982). Both young men and young women in the created models more often include indicators of 2nd group.