Determination of individual teleroentgenographic characteristics of the lower medial incisors position in Ukrainian young men and young women with orthognathic bite

Abstract

Ethnic, sexual and age features of the incisors positions point to the need for the development of techniques that allow to determine their individual characteristics, since commonly accepted standards recommended for optimal positioning of incisors can only be used as indicative. The purpose of the study – by studying teleroentgenographic indices and conducting direct stepwise regression analysis in young men and young women of Ukraine with orthognathic bite, to develop and analyze the mathematical models of individual characteristics of the position of the lower medial incisors. With the Veraviewepocs 3D device, Morita (Japan) in 38 young men (17 to 21 years of age) and 55 young women (aged from 16 to 20 years) with occlusion close to orthognathic bite and balanced faces received side teleroentgenograms. Cephalometric analysis was performed using OnyxCeph3TM software. Cephalometric points and measurements were performed according to the recommendations of A.M. Schwarz, J. McNamara, W.B. Downs, R.A. Holdway, P.F. Schmuth, C.C. Steiner and C.H. Tweed. According to the above methods, in the licensed package “Statistica 6.0” using direct straight line regression analysis, the teleroentgenographic characteristics of the position of the lower medial incisors (distance 1l_NB, distance 1l_APog, angle 1l_DOP, IMPA angle, Mand1_NB angle, FMIA angle and Mand1_MeIm angle) were performed. In young men with orthognathic bite of 7 possible models of teleroentgenographic characteristics of the lower medial incisors, 5 were constructed with determination coefficient R2 from 0.694 to 0.849, and in young women, all 7 possible models with determination coefficient R2 from 0.595 to 0.794. In young men most often the regression equations included - the angle ANB and facial vertical index GL_SN_S (by 11.5%); lower face height ANS_ME, face angle NBA_PTGN and distance S_E (by 7.7%). In young women most often the regression equations included – the angle of N_POG (16.7%); Wits indicator (13.9%); inclination angle I (8.3%); H-angle, maxillo-mandibular angle MM and angle of facial axis NBA_PTGN (by 5.6%). Thus, in the work with the help of the method of stepwise regression with inclusion, among Ukrainians of juvenile age, on the basis of features teleroentgenographic indicators, the analysis of reliable models of individual teleroentgenographic characteristics of the position of the lower medial incisors was developed and carried out.