ASSESSMENT OF THE OCCLUSAL RELATIONS NATURE AT THE STAGES OF ORTHOPEDIC REHABILITATION OF PERSONS WITH PERIODONTAL TISSUE DISEASES COMPLICATED BY DENTITION DEFECTS

Abstract

Resume. According to epidemiological studies, there is still an increased prevalence of periodontal disease among the population of different regions of the world, with increasing intensity and aggressiveness. Long-term chronic generalized lesions of recurrent and progressive inflammatory-dystrophic process lead to the destruction of alveolar processes, pathological mobility of teeth, tooth loss and dentofacial dysfunctions. One of the most characteristic symptoms of generalized periodontitis is the presence of traumatic occlusion. Depending on the degree of pathological changes in periodontal tissues, the size and topography of dentition defects, the replacement of dentition pathologies should be planned by splint-type orthopedic structures and computerized analysis of occlusal relationships with T-Scan III system.
 The aim of the study is to improve the effectiveness of orthopedic treatment of periodontal diseases complicated by defects of the dentition with the control of occlusal relationships with a computerized T-Scan III system.
 Materials and methods. We have examined 87 persons aged between 30 and 69 years with generalized periodontitis of I – III severity, complicated by partial loss of teeth of different sizes and topography, and a control group of the same age in 10 patients with intact dentition and physiological forms of occlusion without clinically diagnosed periodontal diseases.
 Computerized analysis of occlusion indices was performed by the T-Scan III system. We have investigated the stereotype of functional loads according to the following quantitative and qualitative indicators: the index of asymmetry of force between the parts (%); time of occurrence of the maximum amount of dental contacts (sec); time of disclusion (sec); the presence of premature occlusal contacts on the natural teeth and orthopedic constructions, and the presence of changes in the direction of the trajectory of the total vector of occlusal load. 
 Orthopedic rehabilitation of patients in the case of periodontal diseases of the I-II degree of severity and the presence of small defects of the dentition, we conducted by splint-type orthopedic structures, dental implants, and artificial crowns of our own design with discrete occlusal loading (Licence for Effective Model No 143278, Ukraine, MPK А61С 13/007, u 2019 11487: Artificial Crown with Support on a Dental Implant).
 Patients with periodontal diseases of the II – III severity, complicated by defects of dentitions with different size and topography, the dental prosthetics has been performed by traditional removable and combined orthopedic splint-type constructions, and removable splint-type dentures of their own design: "Removable Prosthesis of Splint Type" (Licence for Effective Model No 130980 Ukraine, IPC (2006.01) А61С 13/007, u 2018 03039, 10.01.2019). 
 Computerized analysis of occlusion indicators for the patients of I and II clinical groups and the III control group has been performed before and after orthopedic treatment by T-Scan III system.
 Results of the research. The results of investigation for functional occlusion have demonstrated that the index of relative strength asymmetry between the sides of the dentition in patients with generalized periodontitis complicated by dentition defects increased significantly and led to nonphysiological redistribution of loads compared with indices obtained in patients from control group due to the lack of correspondence for occlusal contacts. These indices are equal to 16.7 ± 3.8% in patients of I group and 18.9 ± 4.8% in group II compared to the similar control indicators – 4.7 ± 1.01%, respectively (p≤0.01). It should be noted that these indicators have differed from the control group indicators according to the severity of the pathological process. Rational prosthetics with removable and non-removable orthopedic structures, including on the base of dental implants, helps to optimize occlusal relations.
 Conclusions. Occlusographic studies performed in patients with generalized periodontitis having different severity and complicated by partial tooth loss have showed increased index of relative strength asymmetry between the sides of chewing, the presence of premature contacts and incorrect location of the trajectory of the total occlusal load vector.
 The dynamics of pathological changes in occlusion indices corresponds to the degree of generalized periodontitis, which indicates the necessity of opportune replacement of dentition defects, taking into account the occlusal relations.
 Rational prosthetics helps to optimize occlusal relations.