Stress analysis of a complete maxillary denture under various drop impact conditions: a 3D finite element study

Abstract

Complete maxillary dentures are one of the most economic and easy ways of treatment for edentulous patients and are still widely used. However, their survival rate is slightly above three years. It is presumed that the failure reasons are not only due to normal fatigue but also emerge from damage based on unavoidable improper usage. Failure types other than long-term fatigue, such as over-deforming, also influence the effective life span of dentures. A hypothesis is presumed, stating that the premature/unexpected failures may be initiated by impact on dentures, which can be related to dropping them on the ground or other effects such as biting crispy food. Thus, the behavior of a complete maxillary denture under impact loading due to drop on a rigid surface was investigated using the finite element method utilizing explicit time integration and a rate-sensitive elastoplastic material model of polymethylmethacrylate (PMMA). Local permanent deformations have been observed along with an emphasis on frenulum region of the denture, regardless of the point of impact. Contact stresses at the tooth-denture base were also investigated. The spread of energy within the structure via wave propagation is seen to play a critical role in this fact. Stress-wave propagation is also seen to be an important factor that decreases the denture's fatigue life.

Algorithm for Designing a Removable Complete Denture (RCD) Based on the FEM Analysis of Its Service Life

“…When constructing the geometric CAD model, the characteristic dimensions of a mandible denture for a 50-year-old male patient were utilized. They are quite comparable with the ones used in [ 12 ]. A 3D scan of the RCDs was chosen as the reference data ( Figure 2 a).…”

“…Behind the premolars, 12 molars are located for the grinding of food under significant cyclic loads. These teeth have a crown shape with a large mastication surface, upon which four to five cusps are present (three in the front and two behind) [ 12 ]. Unlike natural individually fixed teeth, an artificial dentition is attached as a single unit on a polymer base.…”

“…The authors consider it important to cite some papers in the field of the FEM analysis of complete dentures. These papers highlight: (1) the wide application of this approach for solving practically urgent problems, (2) the breadth of the applied models and criteria, and (3) the absence of universal rules for their application [ 12 , 32 , 53 , 54 ].…”

Influence of fibromucosa height and loading on the stress distribution of a total prosthesis: a finite element analysis

“…Several researchers in dentistry have been using FEA to evaluate total prosthesis stresses, such as Nejatidanesh et al [25] which evaluated the influence of muscle cut-offs on the stress concentration in the total prosthesis [25], the stress in the labial frenulum region [26], and the stabilization of the lower total prosthesis [27][28][29].…”