Regression models of teleradiographic parameters according to the Jarabak method in young men and young women with orthognathic occlusion

Abstract

Obtaining orthognathic occlusion in a patient as a result of treatment is a key goal of any orthodontist. However, the thorny path that both the patient and the doctor must go through involves painstaking work, which primarily begins with planning and choosing a method of orthodontic treatment, predicting and modeling its results. However, the latter is possible only if previously conducted research to determine the normative indicators for a population. The aim of the study was to construct and analyze regression models of teleradiographic parameters according to the Jarabak method in Ukrainian young men and young women with orthognathic occlusion. 49 young men and 76 young women with orthognathic occlusion underwent cephalometric analysis of lateral radiographs according to the modification of the method Jarabak J. R. – Roth-Jarabak, performed using the software OnyxCeph³™. All parameters according to the Jarabak method were divided into three groups: the first group included metric characteristics of the skull, which are used as baseline indicators; to the second group – dental-jaw in which the skeleton has already been formed and which surgical methods can change the length, width, angles and positions of the upper and lower jaws; to the third group – indicators that characterize the position of each individual tooth relative to each other, cranial structures and the profile of the soft tissues of the face. Construction of regression models of teleradiographic indicators by the Jarabak method was performed in the licensed package “Statistica 6.0” using step-by-step regression analysis. When modeling teleradiographic parameters according to the Jarabak method, which were included in the second group, depending on the indicators of the first group in young men with orthognathic occlusion, 8 out of 19 possible reliable regression models with a coefficient of determination greater than 0.5 (R2= from 0.589 to 0.950) were constructed. The constructed equations most often include the value of the angle N-S-Ar and the distances Ar-Go and N-S. In young women with orthognathic occlusion, 6 reliable regression models of the second group were constructed depending on the indicators of the first group (R2= from 0.609 to 0.971). The constructed equations most often include the value of the distances Ar-Go, S-Ar, N-S and the angle N-S-Ar. When modeling teleradiographic indicators included in the third group, depending on the indicators of the first and second groups in young men, 5 out of 8 possible reliable regression models with a coefficient of determination greater than 0.5 (R2= from 0.658 to 0.751) were constructed. The constructed equations most often include the values of the angles N-A-Pog, N-Go-Gn, S-N-B and A-N-B. In young women with orthognathic occlusion, 6 reliable regression models of the third group were constructed depending on the indicators of the first and second groups (R2= from 0.509 to 0.772). The constructed regression equations most often include the value of the angles N-A-Pog, A-N-B, S-Ar-Go, S-N-A and the ratio Go_Me:N-S. The obtained models will allow orthodontists to automatically calculate the required cephalometric parameters.