ANALYTICAL APPROACH IN EVALUATING THE RELATIONS OF ODONTOMETRIC INDICATORS AND LINEAR PARAMETERS OF DENTAL ARCS IN PEOPLE WITH VARIOUS FACE TYPES

Aim. Improvement of the analytical approach in the evaluation of the ratios of odontometric parameters and basic linear parameters of dental arches in the physiological occlusion of permanent teeth in people with different types of face.

Materials and methods. A survey of 207 people aged 18-25 years with a full set of permanent teeth, physiological occlusion and various types of face and dental arches was carried out. To determine the dental type of face (normodontia, macrodontia, microdontia), the diagonal dimensions of the facial head were evaluated between the cephalometric points "t" (tragion) and "sn" (subnasale). When establishing the gnathic type of face (mesognathy, dolichognathy, brachygnathy), the gnathic index was calculated, calculated as the percentage of diagonal and transversal dimensions of the facial part of the head. Transversal dimensions represented the width of the face between the goat-bearing landmarks "t-t". Gnathic variants (mesognathy, dolichognathy, brachygnathy) of dental arches (Dmitrienko SV, 2015) were determined taking into account the dental index calculated as the ratio of the half-sum of the width of the crowns of 14 teeth to the width of the dental arch between the second molars. The types of the dental system (normodontia, macrodontia, microdontia) were determined from the results of summation of the width of the crowns of the upper teeth.

Results. The value of the index ratio characterizing the correspondence between the sizes of the upper and lower teeth is 1,065±0,005 for all types of dental arches. The ratio of the sum of the width of the crowns of incisors and canines of the upper jaw to the sizes of the antagonists is 1,3±0,02, and corresponds to the indices calculated by the Bolton method. The ratio of half the value of the sum of 14 teeth to the size of the front-distal diagonal is 1,065±0,005 both on the upper and lower dental arch. The ratio of the diagonal dimensions of the upper dental arch, to the analogous dimension of the lower arch, is, on average, 1,065±0,01 for all types of dental arches.

Conclusion. Optimization of diagnostic methods, in order to improve the effectiveness of orthodontic treatment, adult patients with anomalies of the dentoalveolar system, it is advisable to revise the conventional traditional diagnostic schemes for determining the shape and size of the dental arches. The ratios between odontometric parameters and basic linear parameters of the dental arches of the upper and lower jaws are informative, diagnostically significant values that are of an applied nature in the clinic of orthodontics. Interpretation of these indices can be used to characterize physiological occlusion, to determine the correspondence of the base dimensions of the dental arches of both jaws, and also to predict the shape and size of the dental arches in the treatment of patients with anomalies of occlusion in order to achieve an optimal functional and aesthetic result.