Influence of tension and deformation indicators on the quality of removable constructions acrylic basis

Abstract

Background. The question of distribution of masticatory pressure is one of the main branches in quali­tive manufacturing of removable constructions. With the development of software, as well as with the increase in the power of computer technology has also spread to the problems of biomechanics, in particular the biomechanics of the human oral cavity. The aim of our study was to analyze the results of using the method of finite element techniques with the purpose to improve the quality of prosthetic treatment by correct modeling constructional denture elements. Materials and Methods. The study involved 45 patients aged 44–73 years (mean age 59.2±4.3) treated with complete laminar prosthetic constructions for the upper jaw and lower jaw. A powerful method was developed to solve the problems of the theory of elasticity – the finite element method. The main idea is that the body under the study is divided into a finite number of subdomains or elements on which the desired continuous function is approximated by a polynomial (consists of piecewise continuous functions). A two-dimensional quadrangular element with four nodes was chosen as the partition element. Dividing it into elements and further solving the problem was in the ANSYS Mechanical APDL package (USA). Results. Regarding the calibration of the ultimate displacements of nodal points and as a result of the distribution of masticatory pressure under the basis of a complete removable dentures on the tissues of the prosthetic area, the average values of each plane were as follows: for section PM1 – the plane with high pressure was ([675298.14±5.21] m2K). Taking the PM2 region, the values were slightly higher ([369743.3±3.9] m2K) and ([735356.34±4.52] m2K), respectively. Conclusions. Our findings suggest direct relationship between the using of mathematical calculation of material volume, volume deformation, potential data and elasticity theory as auxiliary element in the manufacture of removable dentures and, as a result, direct influence on level of quality of following constructions. Keywords: orthopedic treatment, finite element method, complete removable dentures, tension theory, deformation.