The simulation of mastication efficiency of the mucous-borne complete dentures

摘要

The aim of this study was to present rules for numerical investigations of mastication efficiency of mucous-borne complete dentures. Finite element method (FEM) large displacements analysis with denture detaching and sliding at mucous membrane interface was employed. The possibility of a lower denture destabilization under oblique mastication load was modeled. Denture stabilization at balancing contact "at time" and "delayed" was modeled with increasing of a distance to the opposite denture. An unfavorable mucous membrane foundation was assumed. Pressures beneath dentures during stable vertical occlusal loadings are lower than pain threshold of mucous membrane even when the denture foundation was very unfavorable. Simulation of realistic oblique mastication force results in a denture destabilization. Denture experienced a large slide, completely lost adherence at balancing side and the balancing contact was needed to achieve stabilization. The pressures beneath denture under oblique load increased to values much higher than pain threshold and the "delayed" balancing contact influenced additional increase of pressure values. In the FEM study only characteristic unfavorable denture foundation and conventional denture type were analyzed. Defined values of pressure beneath dentures show that it is necessary to underlay the dentures. The influence of "delayed" balancing contact on significant increase of stress beneath dentures indicates that in case of a problem with stabilization of dentures it is necessary to introduce stabilization on the implants. Universal rules of conducting a numerical experiment and interpreting its results constitute the base and encouragement to complete further practical tasks awaiting engineers and prosthetists.