Use of finite element analysis for the assessment of biomechanical factors related to pain sensation beneath complete dentures during mastication

Today, an artificial tooth root called a dental implant is used to replace lost tooth function. Treatment with dental implants is considered an effective and safe method. However, in some cases, the use of dental implants had some failures. The success of dental implants is influenced by several biomechanical factors such as loading type, used material properties, shape and geometry of implants, quality and quantity of bone around implants, surgical method, lack of rapid and proper implant surface's integration with the jaw bone, etc. The main purpose of functional design is to investigate and control the stress distribution on dental implants to optimize their performance. Finite element analysis allows researchers to predict the stress distribution in the bone implant without the risk and cost of implant placement. In this study, the stresses created in the 3A.P.H.5 dental implant's titanium fixture and screw due to the change in abutment angles tolerance have been investigated. The results show that although the fixture and the screw's load and conditions are the same in different cases, the change of the abutment angle and the change in the stress amount also made a difference in the location of maximum stress. The 21-degree abutment puts the fixture in a more critical condition and increases the chance of early plasticization compared to other states. The results also showed that increasing the abutment angle to 24 degrees reduces the stress in the screw, but decreasing the angle to 21 degrees leads to increased screw stress and brings it closer to the fracture.

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Effect of number of implants, distal implant inclination, and angled abutment on stresses in fixed complete dentures: a nonlinear finite element analysis

Revista Portuguesa de Estomatologia Medicina Dentária e Cirurgia Maxilofacial ◽

10.24873/j.rpemd.2021.11.847 ◽

2021 ◽

Vol 62 (4) ◽

Author(s):

Tomás Geremia ◽

◽

Leonardo Barcellos ◽

Leandro Corso ◽

Eduardo Villarinho ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Cortical Bone ◽

Three Dimensional ◽

Peak Stress ◽

Complete Dentures ◽

Element Analysis ◽

Von Mises ◽

Three Dimensional Finite Element ◽

Abutment Screw

Objectives: This nonlinear three-dimensional finite element analysis (FEA) study evaluated the effect of the number of implants, distal implant inclination, and use of angled abutments on stress magnitude and distribution in cortical bone (CB), abutment screw (AS), and prosthetic screw (PS) of implant-supported fixed complete dentures. Methods: Nonlinear 3D FEA models of mandibular fixed complete dentures were created with five, four, or three parallel straight implants (5S, 4S, 3S) and with tilted distal implants (5T, 4T, 3T). In addition, the 5T model was tested using angled abutments over the tilted distal implants to re-align the implant inclination. A 100-N axial load was applied over the first molar region (cantilever) to analyze the von Mises stresses in selected points (CB, AS, and PS). Results: The implant adjacent to the load showed the highest stresses in CB, AS, and PS. The model with three implants showed higher stresses than the ones with four and five implants. Peak stresses in the AS increased 40% from five to four implants and 100% from five to three implants. Tilting the distal implants increased stresses in CB. Peak stress in the PS increased 150% from 5S to 5T models and 100% from 4S to 4T models. Angled abutments generated lower stresses on CB and AS but higher stresses on PS. Conclusions: The results suggest that stresses in the cortical bone, abutment screw, and prosthetic screw increase when tilting the posterior implants and reducing the number of implants. The use of angled abutments decreased stresses at the bone-implant interface and in abutment screws but increased stresses on prosthetic screws.

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Influence of Different Soft Liners on Stress Distribution in Peri-Implant Bone Tissue During Healing Period. A 3D Finite Element Analysis

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-11-00049 ◽

2013 ◽

Vol 39 (5) ◽

pp. 575-581 ◽

Cited By ~ 8

Author(s):

Mateus Bertolini Fernandes dos Santos ◽

Rafael Leonardo Xediek Consani ◽

Marcelo Ferraz Mesquita

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Distribution ◽

Three Dimensional ◽

Maximum Principal Stress ◽

Simulation Software ◽

Control Group ◽

Complete Dentures ◽

Element Analysis ◽

Three Dimensional Models

The aim of this study was to evaluate the stress distribution in the bone adjacent to submerged implants during masticatory function in conventional complete dentures with different soft liners through finite element analysis. Three-dimensional models of a severely resorbed mandible with 2 and 4 submerged implants in the anterior region were created and divided into the following situations: (1) conventional complete dentures (control group); and conventional complete dentures with different soft liner materials, (2) Coe-Comfort, (3) Softliner, and (4) Molteno Hard. The models were exported to mechanical simulation software and 2 simulations were done with the load in the inferior right canine (35 N) and the inferior right first molar (50 N). The data were qualitatively evaluated using the maximum principal stress and microstrain values given by the software. The use of soft liners provides decreased levels of stress and microstrains in peri-implant bone when the load was applied to canine teeth. Considering all of the values obtained in this study, the use of softer materials is the most suitable for use during the period of osseointegration.

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