FACTORS OF DECOMPENSATION IN OROFACIAL SYSTEM IN ADULT PATIENTS WITH DEEP OVERBITE

Subject. The depth of the overbite increases with age. With the loss of teeth secondary deformations of the dentition, dysfunctions, teeth wearing, periodontal disease and temporomandibular joint (TMJ) dysfunctions occurs, facial aesthetics is affected. The urgency of the topic depends on the high prevalence of anomaly and self-destruction of the orofacial system (OFS) with deep overbite in adults. The aim was to identify the factors of decompensation of the dentition in adults with deep overbite. Methodology. Clinical (questioning, examination, functional tests), anthropometric (photo analysis, casts’ analysis, Shimbachi index) methods and X-ray analysis(cephalometry, analysis of zonograms of TMJ, orthopantomography) were performed for 84 adult patients with deep overbite more than 3 mm (GRP) and Angle Class I or II. All patients were divided into 2 main groups according to the size of overjet: OG-1 ― 42 people with a normal overjet (2 ± 2 mm) between the incisors; OG-2 ― 42 people with an enlarged overjet (more than 4 mm). We used the MSUMD classification of malocclusion (1991). The results of the examination of the patients in 2 main groups were compared with each other and with the average structure of the OFS in patients with physiological occlusion. We have identified specific clinical, anthropometric, and radiological groups of symptoms of decompensation in OFS, which are common for adults with GRP. Conclusions. In adult patients with GRP the main factor of decompensation in OFS is lower jaw displacement. In the development of displacement of the lower jaw a few factors are important: transversal disproportion of the dentition; sagittal jaw disproportion; loss of posterior teeth. The loss of the teeth, the reduction of the interalveolar height and the associated functional and aesthetic problems are adaptive mechanisms for the displacement of the mandible.