Influence of the thickness of the mucous membrane of the toothless section of the prosthetic bed on the stress-strain state of the biomechanical system “partial removable prosthesis - terminal defect of the dentition of the lower jaw”

The article presents the results of studies on the study of the stress-strain state of the biomechanical system «partial removable prosthesis - terminal defect of the dentition of the lower jaw». The purpose of the paper is formulated as follows: to investigate the stress-strain state of the biomechanical system «partial removable prosthesis - terminal defect of the dentition of the lower jaw» with different thickness of the mucosa of the toothless section. To solve the set goal, the finite element method was used in the work with the ANSYS Academic Research Release 18.2 software package. In this study, the stresses were calculated only under the first and second molars on the lower jaw. A study of the stress-strain state of the tissues of the prosthetic bed (mucous membrane, cortical and spongy tissue) in the region of the terminal defect in the lower jaw was carried out at different thicknesses of the mucosa (0.2, 0.4, 0.6 mm). For greater objectivity and informativeness, each component of the system was considered separately. Investigations of the stress-strain state of the biomechanical system «partial removable prosthesis - terminal defect of the dentition of the lower jaw» showed that the stress-strain state of the elements of the system most significantly depends on the thickness and elastic properties of the mucosa of the prosthetic bed. Increasing the thickness of the mucous membrane of the prosthetic bed to 0.6 mm results in an insignificant increase in the stress fields in the mucous membrane itself, whereas in the cortical and spongy bone the stresses decrease significantly. So the stresses in the cortical bone with a thickness of the mucosa 0.4 mm decrease by 12% compared with the results obtained with a thickness of the mucosa of 0.2 mm. And the voltage decreases by 26% if the mucosa is well-pliable and its thickness is 0.6 mm. Stresses in the spongy bone with a thickness of the mucosa 0.4 mm decrease by 12% compared with the results obtained with a thickness of the mucosa of 0.2 mm. And a 56% reduction in stress occurs if the mucosa is well pliable and its thickness is 0.6 mm.