Examination of morphological and densitometrical symmetry of a temporally mandibular joint (TMj) in patients with dental maxillary anomalies (DMA) is highly important. It can be used during orthodontic patients’ treatment as visualization and objective assessment of TMj in children and adults. Moreover, it is necessary for definition of clinical alleged violations of joint’s structure and function. The purpose of the article is to examine morphological and densitometrical symmetry of TMj at patients from DMA and the patients having a secondary edentia (the III class by Kennedy). From 57 computer tomograms (CT) of the patients having dental maxillary anomalies (DMA), only 39 people who have entered in І group, and a secondary edentia (the III class according to Kennedy) needing prosthetics are investigated: (18 people) – ІІ group. The age of patients was ranging from 8 up to 40 years. By types of DMA according to Engl's classification, it isn't dependent on age. Division of patients was the following: I class – 18 patients (8 – 26 years), II class across Engl – 12 patients (2 – 33 years), and III class across Engl – 6 patients age of 9 – 11 years. 18 patients of orthopedic office of 32-40 years, 6 men and 12 women having a secondary edentia (the III class according to Kennedy) and needing prosthetics are united in the 2nd group. Measurement of TMj on CT was carried out by N.A. Rabukhina's method to I.E. Androsova's modifications and coauthors. The X-ray anatomic density of a bone tissue was measured in the Ez3D2009 application program by means of the “Profile-measurement of density of a bone between two points” tool in terms of Haunsfild (HU). Disregarding average values of TMj heads density separately on the right and at the left, we have found out that depending on a type of dental maxillary density of a bone of heads at anomalies of separate teeth position (the I class) is 440,4±65,6, at the II class – 418,7±62,8; at the III class – 323,5±35,6. Half-scientific data demonstrate that with increase in weight of pathology, namely, with strengthening of not physiological load of TMj response of a bone of a head of a joint is shown in reduction of its density. So, densimetric indicators of the studied parameter at the III class by 1,36 times are lowered in comparison with pathology of the I class across Engl. Assessment of symmetry of TMj heads in the I group between classes on Engl have shown that all patients had a difference between the left and right parties, it was insignificant and had a statistical error р›0,05. At the same time, when comparing indicators of the average size of width of TMj heads in the sagittal plane increase of asymmetry from І a class across Engl to ІІІ is established to a class that is confirmed statistically P‹0,05. Width and height of articulate TMj heads were also examined. Having compared these width of articulate heads of TMj between groups to DMA and a secondary edentia, it was found out that the difference between the right and left heads of TMj in the I group was 0,26 mm; in ІІ to group – 1,01 mm., which shows the increase of asymmetry of heads of TMj at secondary adentiya. To sum up, it was found out that existence of DMA reduces densitometrical indicators of density of TMj heads. Density of a bone of heads is most reduced at the III class and depends on weight of pathology. According to the research’ results the asymmetry increases with age. Asymmetry’s increase of TMj heads form at secondary adentiya is mainly connected with unilateral chewing in the absence of group of teeth on one of the parties. When comparing indicators of the average size of width of TMj heads in the sagittal plane increase of asymmetry from І a class across Engl to ІІІ is established to a class that indicates change of a form of an articulate head of TMj depending on an arrangement of the lower jaw in the sagittal plane.
Keywords: temporally mandibular joint, malocclusion, bone density
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