Relations linear dimensions needed to build the correct form of the dental arch with odontometric and cephalometric indicators in girls-mesocephals with orthognatic bite

Abstract

SUMMARY. A number of studies have established connections of teeth and dental arches with parameters of the cranio-facial complex, however, similar studies have not been carried out in young men and girls of different craniotypes with orthognathic bite.

The aim of the study – to analyze the connections of computer-tomographic sizes needed to build the correct form of the dental arch with odontometric and cephalometric indicators in girls-mesocephals with orthognatic bite.

Material and Metohods. Primary indices of the size of the teeth and heads of girls from Podillia with orthognathic bite (n = 50) were obtained from the data bank of the research center of the M. Pyrohov Vinnytsia National Medical University, within the framework of the agreement on creative cooperation between Vinnytsia National Medical University, and Ukrainian Medical Stomatological Academy (Contract No. 1 dated 05.01.2015).

The research was carried out in accordance with the self-developed scheme using the Veraviewepocs 3D dental cone beam. In the upper and lower incisors, the canines, small and first large angular teeth were measured: the length of the tooth; the length of the root in the vestibular-lingual and mesiodistal projections; mesiodistal crown size of the tooth; vestibular-lingual size; the width of the dentin-enamel border in the mesiodistal direction; the width of the dentin-enamel border in the vestibular-lingual direction. Also, the transversal dimensions of the upper and lower jaw and the sagittal characteristics of the dental arch and cephalometric dimensions were determined. The correlation analysis of the results obtained in girls-mesocephals (n = 16) was performed using the nonparametric Spirman method in the statistical package "Statistica 6.0".

Results and Discussion. In girls-mesocephals with orthognathic bite, the following multiple connections of transversal dimensions of the upper and lower jaw and sagittal characteristics of the dental arch with odometometric and cephalometric indices are established: reversed, predominantly unreliable mean force (r from -0.30 to -0.47) connections of distance between the tops of the palatal roots of the upper first molar teeth, with the majority of mesiodistal and vestibular-lingual dimensions of the crowns of teeth, with all the parameters of the width of the dentin-enamel border in the vestibular-lingual direction and all the indications of distances from the auricular point to the corresponding points on the skull; direct, mostly average strength, unreliable (r ranges from 0.31 to 0.49), a reliable average force (r ranges from 0.50 to 0.59) and strong (r ranges from 0.60 to 0.77) connections of most transversal dimensions of the upper and lower jaw with the majority of mesiodistal dimensions of the crowns of the incisors and jaws of the upper and lower jaws, indexes of the width of the dentin-enamel border in the vestibular-lingual direction of the upper lateral incisors and the canines and the length of the root in the vestibular-lingual and mesiodistal projections of the upper lateral incisors, and also with the vestibular-lingual crown size lower large molar teeth; direct, mostly medium strength, unreliable (r from 0.31 to 0.49), ties of distance between the tops of the medial roots of the upper and lower first large angular teeth with vestibular-lingual crowns of the upper incisors and canines, with most indicators of the width of the dentin-enamel border in the mesiodistal direction and the width of the dentin-enamel border in the vestibular-lingual direction of the lower lateral incisors and canines; direct, predominantly average forces unreliable (r from 0.30 to 0.48) connections distance between the tops of the medial roots of the upper first large angular teeth with most indicators of the length of the upper and lower incisors and the canines; inverse, predominantly mediotive, unreliable (r from -0.31 to -0.47) connections distance between the tops of the root of the jaw of the mandible and one half of the length of the teeth and the length of the root in the vestibular-lingual and mesiodistal projections; direct, mostly average strength, reliable (r from 0.50 to 0.59), unreliable average strength (r from 0.30 to 0.49) and strong (r from 0.60 to 0.86) connections of most transversal dimensions of the upper and lower jaw with almost half of cephalometric indices; direct, mostly of average strength, are reliable (r ranging from 0.50 to 0.59), unreliable average forces (r ranging from 0.30 to 0.49) and strong (r from 0.60 to 0.73) connections of all parameters of the maxillary dental arch in the sagittal plane with the majority of mesiodistal and vestibular-lingual dimensions of the crowns of the teeth and the width of the dentin-enamel border in the mesiodistal and vestibular-lingual directions; inverse, predominantly average, false (r from -0.30 to -0.49) connections of depth of palate at the level of the incisors and at the level of the first small angular teeth with the majority of mesiodistal and vestibular-lingual dimensions of the crowns of the teeth, as well as the depth of the palate on levels of the first large angular teeth with most indicators of distances from the auricular point to the corresponding points on the skull; direct, predominantly average forces unreliable (r from 0.30 to 0.47) connections of the depth of the palate at the level of the first small and large angular teeth with most indicators of the length of the root in the vestibular-lingual projection and the height of individual parts of the face.

Conclusions. 1. Among the linear sizes necessary for constructing the correct form of the dental arch, the relative majority of the reliable and average strength of the false correlations with the size of the teeth and the cephalometric indices in the girls-mesocephals is established with the parameters of the maxillary dental arch in the sagittal plane (45.9 % of the total number of bonds between the given indicators), and the smallest - with parameters of the maxillary dental arc in the vertical plane (32.3 %). 2. Relative majority of reliable and average strength of inaccurate transversal dimensions of the upper and lower jaw in girls-mesocephals is established with vestibular-lingual dimensions of crowns of teeth (33.3 %), with the width of dentin-enamel border in mesiodistal (38.9%) and vestibular-lingual (44.4 %) and with cephalometric indices (41.4 %). 3. Most correlations of the maxillary dental arc parameters in the sagittal plane in the girls-mesocephals are established with mesiodistal and vestibular-lingual dimensions of the crowns of the teeth (correspondingly 66.7 and 80.6 %) and with the width of the dentin-enamel border in the mesiodistal and vestibular-lingual directions (94.4 and 83.3 % respectively); and the parameters of the maxillary dental arc in the vertical plane - with mesiodistal (44.4 %) and vestibular-lingual (41.7 %), the size of the crowns of teeth and with the length of the root in the vestibular-lingual projection (38.9 %).