Models of linear dimensions necessary for constructing the correct shape of the dental arch in boys and girls with a wide face type depending on the characteristics of teleradiometric indicators

Abstract

One of the key tasks of modern orthodontics is the development of individualized approaches to modeling dentalarches taking into account the morphological and functional characteristics of patients. Studying the influence of teleradiometriccharacteristics and three-dimensional parameters of teeth allows to significantly increase the accuracy of orthodontic treatment andthe stability of the obtained results. Particular attention should be paid to age and gender differences that affect the structure of the faceand the ratio of its structures. The expansion of scientific knowledge in this area contributes to the improvement of methods forpredicting and constructing correct forms of dental arches. The aim of the work is to develop and analyze regression models of lineardimensions necessary for constructing the correct shape of the dental arch in Ukrainian young men and young women with aphysiological bite and a wide face type depending on the features of teleradiometric indicators according to the Ricketts method andcomputed tomography dimensions of the teeth. An analysis of primary computed tomograms of 25 Ukrainian young men and 25 youngwomen with a physiological bite and a wide face type was conducted. According to the Ricketts method, “dental”, “skeletal and dento-skeletal” indicators, indicators of “soft tissue aesthetics”, indicators of “craniofacial relationships” and indicators of “internal structures”were determined on lateral teleradiograms. Morphometric parameters of the teeth of the upper and lower jaws in the mesio-distal andvestibulo-oral directions were determined on computed tomograms; as well as the distances necessary for constructing the correctshape of the dental arches. Regression models were constructed using the Statistica 6.0 license package. It was found that both inUkrainian young men with a wide face type and in young women, all 18 possible reliable regression models with a coefficient ofdetermination greater than 0.6 were constructed (respectively in young men R2= from 0.799 to 0.960, p<0.001 in all cases, in youngwomen R2= from 0.660 to 0.950, p<0.001 in all cases). The following percentages of occurrence in the regression equations ofteleradiometric indicators and computed tomography dimensions of teeth were established: in teleradiometric indicators according tothe Ricketts method (37.50 %), the width of the tooth crown in the mesio-distal direction (18.75 %), the distance from the cutting edgeto the dentino-enamel border line of the tooth in the mesio-distal direction to the apex of the tooth root (9.82 %), the width of the dentino-enamel border of the tooth in the mesio-distal direction and the distance from the cutting edge to the apex of the tooth root (8.04 %each). The following percentages of occurrence in the regression equations of the corresponding teeth were also established: in youngmen – upper incisors (17.09 %), upper canines (11.11 %), upper premolar teeth and lower incisors (10.26 % each); in young women–upper incisors (27.68 %), lower incisors (10.71 %) and lower canines (8.93 %). The constructed highly informative regression modelswill allow dentists to reasonably approach the interpretation of the results obtained in patients and implement a more correct approachto orthodontic treatment