CLINICAL APPLICATION OF THE METHOD OF THREE-DIMENSIONAL MODELING OF THE BORDERS OF THE BASE OF A COMPLETE REMOVABLE LAMELLAR DENTURE USING SELF-HARDENING LAMINATE FOR THE BASES OF REMOVABLE DENTURES

Abstract

Objective of the study. Clinical substantiation of the method of three-dimensional modeling of the base boundaries of complete removable lamellar dentures using self-hardening base material acrylic-free plastic. Materials and methods. The study included 20 patients with edentulous upper and lower jaws of different types according to Schroeder and Keller and mucosal classes according to Suplee. At the preliminary examination, the condition of the prosthetic bed, the complete removable lamellar prostheses (CRLD), the shape of the occlusal surface and the articulation-occlusion relationship were assessed. с If necessary, they were corrected. In the absence of a positive result, patients were not included in the study group. If the quality of the CRLD was satisfactory, the prosthesis boundaries were corrected by the method of volumetric modeling using a self-hardening material acrylic-free plastic. The next day, after re-examination and correction, patients underwent electromyographic (EMG) functional chewing tests to assess chewing performance.Control examinations (clinical and EMG) were performed at 30 days, 3 and 6 months. Evaluation of the effectiveness included: analysis of the application of the acrylic-free plastic layer, tightness of fit and fixation of the prosthesis, condition of the mucous membrane (detection of hyperemia or erosion), and inspection of the structure (integrity, quality of connections, surface smoothness). For objective assessment, electromyography was used using the M-Test complex. Functional chewing tests were performed: before modeling; after correction; after 1, 3 and 6 months of prosthesis use. The effectiveness of the method was determined by the increase in the force of masticatory pressure (MP) in different areas of the prosthetic bed relative to the baseline values. Scientific novelty. In recent years, the number of patients with complete absence of teeth has been growing. The need for orthopedic treatment for people over 60 reaches 100%, and the prevalence of complete removable laminate dentures (CRLDs) in Ukraine is on average 57.5 patients (77.35 dentures) per 1000 people surveyed. The effectiveness of CRLDs is determined by their fixation and stabilization, but according to studies, 20-26% of patients refuse to use them, and 52% have problems with retaining the prosthesis.The key factor in stabilization is the correct formation of contact between the mucosa and the outer surface of the base. The masticatory and facial muscles change the relief of the prosthetic bed, so three-dimensional modeling of the outer surface and edges of the base is considered an effective way to improve stabilization. Existing methods involve functional impressions and the production of a new CRLD, but do not guarantee high-quality fixation. In case of unsatisfactory stabilization of the finished dentures, adhesive materials are used, but their effect is temporary.Conclusions. The application of the proposed method of volumetric modeling of the base boundaries provides reliable fixation of CRLD with unsatisfactory fixation, ensuring an increase in masticatory pressure from 12.09% immediately after correction of the CRLD boundaries to 22.44% after 6 months of use. In the process of adaptation after volumetric modeling of the CRLD base boundaries in the orthopedic treatment of patients with edentulous jaws, there is a redistribution of the increase in the chewing pressure between the working and balancing sides, its severity depends on the localization of edentulous jaws and the period of use of prostheses after the correction.