Numerical Analysis of Dental Caries Effect on the Biomechanical Behavior of the Periodontal System

2015 ◽  
Vol 6 (3) ◽  
Author(s):  
Ali Merdji ◽  
Noureddine Della ◽  
Ali Benaissa ◽  
Bel-Abbes Bachir Bouiadjra ◽  
Boualem Serier ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Dental Caries ◽  
Alveolar Bone ◽  
Root Resorption ◽  
Equivalent Stress ◽  
Three Dimensional ◽  
Fe Method ◽  
Biomechanical Behavior ◽  
Von Mises ◽  
Cervical Level

The aim of this study was to investigate the effect of dental caries on the stability of the periodontal system. This study presents a numerical analysis performed with three-dimensional (3D) finite element (FE) method to evaluate stresses in the bone surrounding the tooth with dynamic mastication combined loadings. In this work, we present a comparative study on infected and healthy periodontal systems. The infected tooth was modeled and a caries defect was introduced to the tooth coronal part. The infected tooth was evaluated and equivalent von Mises interface stress values were obtained for comparison with the ones exhibited by the healthy tooth. Our results by 3D FE analysis indicated that maximum stresses occurred primarily at the cervical level of root and alveolar bone. In the cortical bone, the stress value was greater in infected system (21.641 MPa) than in healthy system (15.752 MPa), i.e., a 37.4% increase. However, in the trabecular bone we observed only 1.6% increase in the equivalent stress values for the infected tooth model. Stress concentration at the cervical level may cause abnormal bone remodeling or bone loss, resulting loss of tooth attachment or bone damage. Our findings showed that decayed single-rooted teeth are more vulnerable to apical root resorption than healthy teeth. The numerical method presented in this study not only can aid the elucidation of the biomechanics of teeth infected by caries but also can be implemented to investigate the effectiveness of new advanced restorative materials and protocols.

Biomechanical Behavior of All-Ceramic Crowns with Variable Thicknesses of Zirconia Frameworks

2016 ◽  
Vol 835 ◽  
pp. 97-102
Author(s):  
Liliana Porojan ◽  
Florin Topală ◽  
Sorin Porojan
Keyword(s):  
Mechanical Behavior ◽  
Equivalent Stress ◽  
The Finite Element Method ◽  
Static Loads ◽  
Biomechanical Behavior ◽  
All Ceramic ◽  
Ceramic Crowns ◽  
Von Mises Equivalent Stress ◽  
Von Mises ◽  
Posterior Restorations

Zirconia is an extremely successful material for prosthetic restorations, offering attractive mechanical and optical properties. It offers several advantages for posterior restorations because it can withstand physiological posterior forces. The aim of the study was to achieve the influence of zirconia framework thickness on the mechanical behavior of all-ceramic crowns using numerical simulation. For the study a premolar was chosen in order to simulate the mechanical behavior in the components of all-ceramic crowns and teeth structures regarding to the zirconia framework thickness. Maximal Von Mises equivalent stress values were recorded in teeth and restorations. Due to the registered maximal stress values it can be concluded that it is indicated to achieve frameworks of at least 0.5 mm thickness in the premolar area. Regarding stress distribution concentration were observed in the veneer around the contact areas with the antagonists, in the framework under the functional cusp and in the oral part overall and in dentin around and under the marginal line, also oral. The biomechanical behavior of all ceramic crowns under static loads can be investigated by the finite element method.

scholarly journals Análise numérica de ligação parafusada semirrígida em perfis formados a frio

ForScience ◽  
2019 ◽  
Vol 7 (2) ◽  
Author(s):  
Emerson Cardoso de Castro ◽  
Flávio Teixeira de Souza ◽  
Arlene Maria Cunha Sarmanho
Keyword(s):  
Numerical Analysis ◽  
Numerical Model ◽  
Finite Elements ◽  
Three Dimensional ◽  
Structural Performance ◽  
Similar Tendency ◽  
Von Mises ◽  
Von Mises Stresses ◽  
Bolt Connection ◽  
Force Displacement

O presente trabalho constitui-se de uma análise numérica, por meio de elementos finitos, objetivando a reprodução via software de um ensaio experimental de ligação parafusada semirrígida em perfis formados a frio, dada no âmbito tridimensional. A análise consistiu-se a partir da reprodução da geometria do protótipo, das condições de contorno e aplicação de carregamento. Para melhor previsão do comportamento da ligação, foram inseridas ao modelo a não linearidade física e geométrica. Foram obtidas as curvas força-deslocamento e a evolução das tensões de Von Mises para os diferentes componentes do protótipo. Os resultados indicaram que o modelo numérico é cerca de duas vezes mais rígido que o experimental. Todavia, foi possível observar que o comportamento do modelo numérico possui tendência similar ao do modelo experimental e também foi possível avaliar a contribuição dos elementos da ligação para o desempenho da mesma.Palavras-chave: Análise numérica. Ligação parafusada semirrígida. Perfis formados a frio. Desempenho estrutural.Numerical analysis of semi-rigid bolt connection in cold formed profilesAbstractThe current paper is based on a numerical analysis by means of finite elements aiming at the software reproduction of an experimental test of semi-rigid bolt connection in cold formed profiles occurred in the three-dimensional scope. The analysis consisted of the reproduction of the prototype geometry, the boundary conditions, and the loading application. For a better forecast of the connection behavior, physical and geometric non-linearity were inserted to the model. The force-displacement curves and the evolution of the Von Mises stresses for the different prototype components were obtained. The results indicated that the numerical model is about twice as rigid as the experimental one. However, it was possible to observe that the behavior of the numerical model has a similar tendency  if compared to  the experimental model and it was still possible to evaluate the contribution of the connection elements to its performance.Keywords: Numerical analysis. Semi-rigid bolt connection. Cold-formed profiles. Structural performance.

Modeling and Simulation Research of Banded Wedge and Synchronous V Belt Drive

2013 ◽  
Vol 677 ◽  
pp. 219-224
Author(s):  
Ying Wu ◽  
Xu Zhou
Keyword(s):  
Simulation Analysis ◽  
Equivalent Stress ◽  
Three Dimensional ◽  
Transmission Mechanism ◽  
Von Mises Stress ◽  
Belt Drive ◽  
Total Deformation ◽  
Stress Changes ◽  
Simulation Results ◽  
Von Mises

For cutting down the stress and displacement of banded wedge and synchronous V belt drive in the transmission process, promoting the transmission mechanism, and improving quality of the belt drive, the working principle of the transmission mechanism was introduced briefly. The three dimensional solid model of the transmission mechanism constituted in pro/e; the main parameters of the model were set using ANSYS Workbench. And then the serialization simulation analysis of the transmission mechanism was achieved when the tension force is located in the point of the V belt entering meshing with the driven wheel; the cloud diagram of Von Mises stress and the maximal Von Mises stress and total deformation of the transmission mechanism were elicited. The simulation results were analyzed. The simulation results show that maximal total deformation has a minimum value with increasing the tensioning force. Reducing becomingly the tensioning force in ensuring natural belt drive the maximal Von Mises stress reduces effectively. Augmenting the active force the maximal equivalent stress rarely reduces and the maximal total deformation remains unchanged. Adjusting opportunely the location of the tensioning force the total deformation reduces effectively and the maximum equivalent stress changes smaller.

scholarly journals Elastic stress concentration at radial crossholes in pressurized thick cylinders

2007 ◽  
Vol 42 (6) ◽  
pp. 461-468 ◽  
Author(s):  
T Comlekci ◽  
D Mackenzie ◽  
R Hamilton ◽  
J Wood
Keyword(s):  
Stress Concentration ◽  
Maximum Stress ◽  
Equivalent Stress ◽  
Three Dimensional ◽  
Maximum Principal Stress ◽  
Radius Ratio ◽  
Graphical Form ◽  
Element Analysis ◽  
Parametric Finite Element Analysis ◽  
Von Mises

Results of a parametric finite element analysis investigation of stress concentration at radial crossholes in pressurized cylinders are presented in numerical and graphical form. The analysis shows that the location of maximum stress does not generally occur at the junction between the bores, as is commonly supposed, but at some small distance up the crosshole from the junction. Maximum stress concentration factors (SCFs) are defined on the basis of the maximum principal stress, von Mises equivalent stress, and stress intensity. Three-dimensional plots of the SCF against the cylinder radius ratio b/a and the crosshole-to-main-bore-radius ratio c/a are presented. The SCFs were found to vary across the range of geometries considered with local minima identified within the parameter range in most cases. The results therefore allow designers to select optimum b/a and c/a ratios to minimize stress concentration in real problems.

A Three-Dimensional Finite Element Stress Analysis and Strength Prediction of CFRP Adhesive Laminated Plates Subjected to Static and Impact Out-of-Plane Loadings

2009 ◽  
Author(s):  
Yukiya Noshita ◽  
Toshiyuki Sawa ◽  
Yuya Omiya
Keyword(s):  
Equivalent Stress ◽  
Three Dimensional ◽  
Laminated Plates ◽  
Stress Distributions ◽  
Maximum Value ◽  
Out Of Plane ◽  
Dimensional Finite Element ◽  
Von Mises Equivalent Stress ◽  
Von Mises ◽  
Three Dimensional Finite Element

Stress distributions in CFRP adhesive laminated plates subjected to static and impact out-of-plane loadings are analyzed using a three-dimensional finite-element method (FEM). For establishing an optimum design method of the laminated plates, the effects of some factors are examined. As the results, it is found that the maximum value of the von Mises equivalent stress σ eqv occurs at the edge of the CFRP’s interfaces. The maximum value of interface shear stress r i at CFRP interface decreases as the reinforced Young’s modulus and the thickness increases. However, the maximum value of σ eqv at the adhesive layer decreases as the reinforced Young’s modulus and the thickness decreases. In addition, the maximum value of r i at the CFRP’s interface of lower reinforced laminates under impact loadings shows opposite characteristics to those under static loadings. For verification of the FEM calculations, experiments were carried out to measure the strains at the interfaces and the laminates plates strengths. Concerning strain and strength prediction based on von Mises equivalent stress, fairly good agreements were found between the numerical and the experimental results. The FEM results of impacted strain are in fairly good consistent with the measured results. Discussion is made on the effects of some factors on interface stress distributions.

Computing Simulation of the Influence of Plate Design, Material, and Screw Positioning on Biomechanical Behavior of Ulna Bone Plates

2013 ◽  
Vol 583 ◽  
pp. 115-118
Author(s):  
Mirela Toth-Tascau ◽  
Flavia Bălănean ◽  
Mircea Krepelka ◽  
Lucian Rusu ◽  
Cristian Toader-Pasti
Keyword(s):  
Material Properties ◽  
Equivalent Stress ◽  
Three Dimensional ◽  
Bone Plate ◽  
Stabilization System ◽  
Three Dimensional Model ◽  
Biomechanical Behavior ◽  
Plate Design ◽  
Element Simulation ◽  
Computing Simulation

Throughout history, fractures have been treated by immobilization, traction, and internal fixation. Construction of a stabilization system composed of bone plate and screws combination depends on factors such as type of fracture, biomechanical behavior of stabilization system, and surgical preference. In this study, the influence of plate design, material properties, and screw placement was investigated through the use of Experimental Design and Finite Element simulation. A three dimensional model of the ulna bone was reconstructed from computer tomography images and a simple oblique fracture was simulated. The fracture was stabilized in different modes, using combinations of three different design plates with the material properties of stainless steel and titanium alloy fixed with three, four, and six screws. The biomechanical behavior was compared in terms of equivalent stress and total deformation. Results showed that the fixation mode and plate design have the largest influence on the biomechanical behavior of the bone-plate assembly.

scholarly journals Biomechanical behavior of overdentures supported by different implant position and angulation using Micro ERA® system

2019 ◽  
Vol 18 ◽  
pp. e191667
Author(s):  
Felipe Franco Ferreira ◽  
Guilherme Almeida Borges ◽  
Letícia Del Rio Silva ◽  
Daniele Valente Velôso ◽  
Thaís Barbin ◽  
...  
Keyword(s):  
Finite Element ◽  
Tensile Stress ◽  
Equivalent Stress ◽  
Lateral Incisor ◽  
Von Mises Stress ◽  
Element Analysis ◽  
Bone Implant ◽  
Implant Position ◽  
Biomechanical Behavior ◽  
Von Mises

Aim: The aim of this study was to investigate the biomechanical behavior of implant-retained mandibular overdentures using Micro ERA® system with different implant position and angulation by finite element analysis (FEA). Methods: Four 3D finite element models of simplified mandibular overdentures were constructed, using one Bränemark implant with a Micro ERA® attachment. The implant was positioned on the canine or lateral incisor area with an angulation of either 0º (C-0º; LI-0º) or 17º (C-17º, LI-17º) to the vertical axis. A 100 N axial load was applied in one side simultaneously, from first premolar to second molar. In all models it was analyzed the overdenture displacement, compressive/tensile stress in the bone-implant interface, and also the von Mises equivalent stress for the nylon component of the housing. The stresses were obtained (numerically and color-coded) for further comparison among all the groups. Results: The displacement on the overdenture was higher at the posterior surface for all groups, especially in the C-17º group. When comparing the compressive/tensile stress in the bone-implant interface, the lateral-incisor groups (LI-0º and LI-17º) had the highest compressive and lowest tensile stress compared to the canine groups (C-0º and C-17º). The von Mises stress on the nylon component generated higher stress value for the LI-0º among all groups. Conclusions: The inclination and positioning of the implant in mandibular overdenture interferes directly in the stress distribution. The results showed that angulated implants had the highest displacement. While the implants placed in the lateral incisor position presented lower compressive and higher tensile stress respectively. For the attachment the canine groups had the lowest stress.

scholarly journals Analytical Methods and Finite Element Method Computation The dental - periodontal tissues response

2017 ◽  
Vol 54 (4) ◽  
pp. 777-780
Author(s):  
Cristina Bica ◽  
Krisztina Martha ◽  
Dorin Bica ◽  
Daniela Esianu ◽  
Madalina Nicoleta Matei
Keyword(s):  
Alveolar Bone ◽  
Equivalent Stress ◽  
Equation System ◽  
Von Mises Stress ◽  
Vertical Force ◽  
Periodontal Tissues ◽  
Spatial Coordinates ◽  
Von Mises Equivalent Stress ◽  
Von Mises ◽  
Tooth Axis

The study of the biomechanical behaviour of dental-periodontal structures during orthodontic movement has been carried out on the basis of the analysis of values of equivalent stress following Von Mises theory, of the stress after the direction of the sz vertical force, which constitutes the essential component of the Von Mises equivalent stress, as well as on the basis of registering the deformities on the tooth axis. The processes of implementation, modelling, calculation and interpretation, using FEM, involved the following steps: defining the geometry and the structure of the model under analysis; meshing the geometry of the structure; connecting the nodal elements; defining the limit conditions and restrictions; loading the created model with vertical forces of different intensities; solving the equation system, having as unknowns in the nodes the following: movement, tension, tension on the spatial coordinates, Von Mises stress. We simulated the orthodontic intrusion through the application of some vertical forces with different intensities and on structures with alveolar bone loss. The tension values in the tooth axis vary in direct proportion to the level of resorption of the alveolar bone, but the decisive element is the numerical value of the applied force, and not the absorption level.

scholarly journals Steel Fibre Reinforced Concrete Meso-Scale Numerical Analysis

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Zhengwei Li ◽  
Meizhong Wu ◽  
Jiawei Wu ◽  
Yujun Cui ◽  
Xingwei Xue
Keyword(s):  
Reinforced Concrete ◽  
Numerical Analysis ◽  
Steel Fibre ◽  
Three Dimensional ◽  
Crack Model ◽  
Fibre Reinforced Concrete ◽  
Steel Fibre Reinforced Concrete ◽  
Geometry Model ◽  
Von Mises ◽  
Meso Scale

Concrete is a heterogeneous composite consisting of aggregate, cement paste, and void. Steel fibre reinforced concrete (SFRC) has been widely studied experimentally and numerically in recent decades. The fibre geometry model program generated by a secondary development ANSYS program was exported to midas FEA for analysis. The constitutive concrete model adopts the total strain crack model of concrete. A steel fibre bond slip is considered in an equivalent manner using the von Mises model. The results of the three-dimensional meso-scale numerical analysis method agree well with the experimental values of steel fibre concrete beams.

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