CONNECTIONS OF COMPUTER-TOMOGRAPHIC CHARACTERISTICS OF DENTAL ARCHES WITH ODONTOMETRIC AND CEPHALOMETRIC INDICES OF BRACHYCEPHALIC GIRLS WITH ORTHOGNATHIC BITE

Abstract

For correct modeling of the shape of the dental arch, it is necessary to establish the most informative interrelated tooth parameters and the head.

The aim of the study – to carry out an analysis of the correlations of CT-sizes necessary for the construction of the correct form of the dental arch with odontometric and cephalometric characteristics of brachycephalic girls with orthognathic bite.

Materials and Metohods. The research was carried out in accordance with the self-developed scheme using the Veraviewepocs 3D dental cone beam. Measurements of the following sizes of upper and lower incisors, canines, small and first large angular teeth (respectively, SAT and LAT ): length of the tooth, root length in vestibule-tongue and mesiodistal projections, mesiodistal and vestibuletongue sizes crowns of the tooth, width of dentineenamel boundaries in mesiodistal and vestibule-tongue directions. Also, the transversal dimensions of the upper and lower jaw and sagittal characteristics of the dental arch and cephalometric dimensions were determined. The correlation analysis of the results obtained in girls-mesocephals (n = 26) was performed using the nonparametric Spirman method in the statistical package "Statistica 6.0".

Results and Discussion. In brachycephalic girls with orthognathic bite, 348 reliable and average strength of false connections were detected out of 1116 possible (31.2 %, of which 17.9 % of false median force) with dental arc parameters in the frontal plane (of which 6 – 0.5 % of direct strong; 132 – 11.8 % of direct average strength; 181 – 16.2 % of false direct average forces; 10 – 0.9 % of reciprocal average strength; 19 – 1.7 % of unreliable reciprocal average forces); 79 out of 279 possible (28,3%, of which 14,3% are unreliable average forces) with parameters of maxillary dental arches in the sagittal plane (of which 3 – 1.1 % of direct strong; 34 – 12.2 % direct average strength; 35 – 12.5 % of false direct middle forces; 2 – 0.7 % of reciprocal average strength; 5 – 1.8 % of false reciprocal average forces); 88 out of 279 possible (31.5 %, of which 12.9 % of the unreliable mean strength) with the parameters of the maxillary dental arch in the vertical plane (of which 2 – 0.7 % of direct strong; 50 – 17.9 % direct average strength; 36 – 12.9 % of false direct middle forces).

Conclusions. 1. In brachycephalic girls, in all groups the reliable and average strength of the unreliable correlations of the linear sizes necessary for the correct form of the dental arch with dental size and cephalometric indices have almost the same percentage – 31.2 % with transversal dimensions of the upper and lower jaw; 28.3 % with parameters of maxillary dental arch in sagittal plane and 31.5 % with parameters of maxillary dental arch in vertical plane. 2. Relative majority of reliable and average strength of inaccurate correlations of transversal dimensions of the upper and lower jaw in brachycephalic girls is established with the vestibule-tongue size of crowns of teeth (34.7%), with teeth lengths (44.2%) and with the width of dentin-enamel boundaries in the mesiodistal direction (30.6 %). 3. Most correlations of the parameters of the maxillary dental arch in the sagittal plane in brachycephalic girls are established with mesiodistal dimensions of crowns of teeth (55.6 %), with the width of the dentin-enamel border in the mesiodistal (55.6 %) and vestibule-tongue (38.9 %) directions and with the length of the root in the vestibule-tongue (44.4 %) and mesiodistal (38.9 %) projections; and the parameters of the maxillary dental arc in the vertical plane – with mesiodistal (52.8 %) and vestibule-tongue (63.9 %) sizes of crowns of teeth and with the width of the dentin-enamel border in the vestibule-tongue direction (44.4 %).