METHOD FOR DIAGNOSTICS OF PLACE DEFICIT IN DENTITION Russian patent published in 2018 - IPC A61B5/00 

FIELD: medicine.

SUBSTANCE: models of the dental arch of the upper and/or lower jaw are obtained, the sum of the mesiodistal dimensions of the twelve teeth is determined according to the model: right and left first permanent molars, first and second premolars, canines, lateral and central incisors (Σ₁₂). The longitudinal length of the dentition in the area of twelve teeth is determined, for which the dentition is divided into six segments of two teeth from the first permanent molar to the right to the first permanent molar to the left : S1 is right first permanent molar and second premolar; S2 is right first premolar and canine; S3 is right lateral and central incisors; S4 is left lateral and central incisors; S5 is left first premolar and canine; S6 is left first permanent molar and the second premolar, and the sum of the mesiodistal dimensions of each segment is obtained (Σ_S1-S6). The average value of the greatest depth of dentition curvature is determined from the right and from the left in the vertical direction, for which a meter is used to determine the vertical distance to the tangent from the incisors to the molars in the area of premolars. The planned change in the dentition width in the transversal direction near the first permanent molars is determined, for which the standard is subtracted from the existing distance between the first molars, to determine the standard, the distance between the most prominent apical mandible basis points at the level of the middle of the first permanent molars crowns is obtained on the lower dentition model, and a value is subtracted therefrom, corresponding to the individual value of the distance between the center of crossing of longitudinal and transverse fissures of the lower first permanent molars for the lower jaw, and the distance between medial palatal bumps of upper first permanent molars for the upper jaw. The angle of central incisors inclination relative to the jaw base and the angle of inclination of the incisors planned during correction in the direction of protrusion or retraction, taking into account the effect on the dental arch length, are determined using head teleradiography in the lateral projection, for which the upper lower angle formed between the plane of the upper jaw base and the longitudinal axis of the central upper incisors is measured, and the standard of 110° is subtracted from the obtained value; for the lower jaw, the inner upper angle between the plane of the mandible body and the longitudinal axis of the central lower incisors is measured and the standard of 95° is subtracted from the obtained value. Based on the data obtained, the place deficit in the dental arch is calculated using the formula TPD=X+Y±W:Km±Z×Kp, where TPD is the true place deficit, taking into account the individual possibilities of orthodontic correction in a patient with dentoalveolar anomalies, in mm; X is discrepancy between the longitudinal length of the dental arch expected after correction and the actual anomalous length, in mm; X=Σ₁₂-Σ_S1-S6; Y is the average value of the greatest depth of dentition curvature to the right and left in the region of lateral teeth, in mm; W is the planned change of dentition width in the transverse direction in the region of the first permanent molars, in mm; W has a negative "-" sign when the dentition is narrowed; Km is the coefficient of dental arch length variation dependence on the change in the dentition width in the region of the first permanent molars; Km for the upper dentition is 1.5, Km for the lower dentition is 1.75; Z is the planned angle of incisors inclination in the direction of protrusion or retraction, taking into account the effect on the dental arch length, is determined in mm; Z has a positive "+" sign when the incisors protrusions are eliminated, Z has a negative "-" sign when the incisors retraction is eliminated. Kr is the coefficient of dental arch length changes dependency on changes in incisors inclination concerning the point of force application to rotate the incisors, Kr=0.5 in case of vestibular change of the inclination angle of the upper incisor relative to the tooth resistance point, Kr=0.8 in case of the axis of rotation through the root tip, Kr=0 in case of the axis of rotation through the tooth cutting edge.

EFFECT: method allows to increase the accuracy of place deficit determination in the dentition for further planning of orthodontic correction.

2 tbl, 9 dwg, 4 ex