scholarly journals Biomechanical Behavior Evaluation of a Novel Hybrid Occlusal Splint-Mouthguard for Contact Sports: 3D-FEA

2021 ◽  
Vol 10 (1) ◽  
pp. 3
Author(s):  
Les Kalman ◽  
Amanda Maria de Oliveira Dal Piva ◽  
Talita Suelen de Queiroz ◽  
João Paulo Mendes Tribst

Background: Orofacial injuries are common occurrences during contact sports activities. However, there is an absence of data regarding the performance of hybrid occlusal splint mouthguards (HMG), especially during compressive loading. This study amid to evaluate the biomechanical effects of wearing a conventional custom mouthguard (MG) or the HMG on the teeth, bone, and the device itself. Methods: To evaluate the total deformation and stress concentration, a skull model was selected and duplicated to receive two different designs of mouthguard device: one model received a MG with 4-mm thickness and the other received a novel HMG with the same thickness. Both models were subdivided into finite elements. The frictionless contacts were used, and a nonlinear analysis was performed simulating the compressive loading in occlusion. Results: The results were presented in von-Mises stress maps (MPa) and total deformation (mm). A higher stress concentration in teeth was observed for the model with the conventional MG, while the HMG design displayed a promising mechanical response with lower stress magnitude. The HMG design displayed a higher magnitude of stress on its occlusal portion (7.05 MPa) than the MG design (6.19 MPa). Conclusion: The hybrid mouthguard (HMG) reduced (1) jaw displacement during chewing and (2) the generated stresses in maxillary and mandibular teeth.

Author(s):  
Les Kalman ◽  
Amanda Maria de Oliveira Dal Piva ◽  
Talita Suelen de Queiroz ◽  
João Paulo Mendes Tribst

Orofacial injuries are common occurrences during contact sports activities; however, there is an absence of data regarding the performance of hybrid occlusal splint mouthguards, especially during compressive loading. To evaluate the total deformation and stress concentration, a skull model was selected and duplicated to receive two different designs of mouthguard devices: one model received a conventional custom-made mouthguard (MG) with 4-mm thickness and the other received a novel hybrid occlusal splint-mouthguard (HMG) with the same thickness. Both models were subdivided into finite elements. The frictionless contacts were used, and a nonlinear analysis was performed simulating the compressive loading in occlusion. The results were presented in von-Mises stress maps (MPa) and Total Deformation (mm). A higher stress concentration in teeth was observed for the model with the conventional MG, while the HMG design displayed a promising mechanical response with lower stress magnitude. The HMG de-sign displayed a higher magnitude of stress on its occlusal portion than the MG design. The hybrid mouthguard (HMG) reduced (1) jaw displacement during chewing and (2) the generated stresses in maxil-lary and mandibular teeth.


2010 ◽  
Vol 04 (04) ◽  
pp. 374-382 ◽  
Author(s):  
Oguz Eraslan ◽  
Ozgur Inan ◽  
Asli Secilmis

Objectives: The biomechanical behavior of the superstructure plays an important role in the functional longevity of dental implants. However, information about the influence of framework design on stresses transmitted to the implants and supporting tissues is limited. The purpose of this study was to evaluate the effects of framework designs on stress distribution at the supporting bone and supporting implants.Methods: In this study, the three-dimensional (3D) finite element stress analysis method was used. Three types of 3D mathematical models simulating three different framework designs for implant- supported 3-unit posterior fixed partial dentures were prepared with supporting structures. Convex (1), concave (2), and conventional (3) pontic framework designs were simulated. A 300-N static vertical occlusal load was applied on the node at the center of occlusal surface of the pontic to calculate the stress distributions. As a second condition, frameworks were directly loaded to evaluate the effect of the framework design clearly. The Solidworks/Cosmosworks structural analysis programs were used for finite element modeling/analysis.Results: The analysis of the von Mises stress values revealed that maximum stress concentrations were located at the loading areas for all models. The pontic side marginal edges of restorations and the necks of implants were other stress concentration regions. There was no clear difference among models when the restorations were loaded at occlusal surfaces. When the veneering porcelain was removed, and load was applied directly to the framework, there was a clear increase in stress concentration with a concave design on supporting implants and bone structure.Conclusions: The present study showed that the use of a concave design in the pontic frameworks of fixed partial dentures increases the von Mises stress levels on implant abutments and supporting bone structure. However, the veneering porcelain element reduces the effect of the framework and compensates for design weaknesses. (Eur J Dent 2010;4:374-382)


2011 ◽  
Vol 86 ◽  
pp. 850-853 ◽  
Author(s):  
Ming Feng ◽  
Guang Rong Yan

As a novel power transmission component, the skewed–roller slipping clutch (SRSC) produces resisting torque depending on relative rotation and sliding between askew arranged cylindrical rollers and specially curved races. In this paper, the surface contact stress and von Mises stress between the rollers and the races are calculated and the effects of roller profile modification on reducing stress concentration are investigated under frictional contact and dynamic equilibrium of the rollers and races.


2004 ◽  
Vol 08 (01) ◽  
pp. 35-41
Author(s):  
Hirotaka Sano ◽  
Norikazu Yamada ◽  
Shingo Maeda

In the current study, using the arthrogram, we developed two-dimensional finite element (FE) models of the human hip joint. To clarify the relationship between the stress distribution and the degree of acetabular dysplasia, three FE models were established and analyzed. The models varied only in the degree of the bony covering of the femoral head; i.e. the center-edge (CE) angle=20, 10, 0 degrees. An edge load (x=0 N, y=600 N) was then applied on the distal border of the femur to simulate the bearing of the body weight. In the CE=20 degree model, no definite stress concentration was seen at the site of the labrum. On the other hand, the stress concentration was seen from the attachment of the labrum to the superior aspect of the acetabulum in the CE=0 degree model. The site of stress concentration clearly corresponded to the lesions where the acetabular rim pathologies were seen in the clinical practice. Moreover, we found that the Von Mises stress increases dramatically with decreasing the CE angle at the attachment of the labrum. In the dysplastic hip, the mechanical stress increases significantly at the supero-lateral aspect of the acetabulum, which eventually leads to the tearing or detachment of the labrum.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Z. Q. Zhang ◽  
J. L. Yang

Background. Cranial sutures are deformable joints between the bones of the skull, bridged by collagen fibres. They function to hold the bones of the skull together while allowing for mechanical stress transmission and deformation.Objective. The aim of this study is to investigate how cranial suture morphology, suture material property, and the arrangement of sutural collagen fibres influence the dynamic responses of the suture and surrounding bone under impulsive loads.Methods. An idealized bone-suture-bone complex was analyzed using a two-dimensional finite element model. A uniform impulsive loading was applied to the complex. Outcome variables of von Mises stress and strain energy were evaluated to characterize the sutures’ biomechanical behavior.Results. Parametric studies revealed that the suture strain energy and the patterns of Mises stress in both the suture and surrounding bone were strongly dependent on the suture morphologies.Conclusions. It was concluded that the higher order hierarchical suture morphology, lower suture elastic modulus, and the better collagen fiber orientation must benefit the stress attenuation and energy absorption.


2021 ◽  
Vol 29 (2) ◽  
Author(s):  
Saddam Hussein Raheemah ◽  
Kareem Idan Fadheel ◽  
Qais Hussein Hassan ◽  
Ashham Mohammed Aned ◽  
Alaa Abdulazeez Turki Al-Taie ◽  
...  

The present study aims to investigate crack presence in a rigid steel beam so that it can be considered in structural design. A finite element method (FEM) had been used with the Ansys 16.1 software to simulate the whole steel body with three different forces and moments with a magnitude force subjected at the free end of the beam. The steel rod had been considered as simple cantilever to be modelled by the software. Von Mises stress had been considered in the simulation process where the maximum value of stress due to applied load and moment was 1.9 MPa. Total deformation of the whole body had also been considered to instigate the maximum deformation (4.3mm) due to applied loads and moments. Furthermore, MATLAB and through fuzzy logic had been used to assist in the investigation of cracks. Both approaches had been governed by the Euler-Bernoulli theory for free vibration of motion equations. The other aim of this study is to evaluate results received from the Ansys with MATLAB for the same boundary conditions as the case.


MESIN ◽  
2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Teddy Andreas ◽  
Tono Sukarnoto ◽  
Soeharsono Soeharsono

<p><em>The PPCW railroad flatcars is railroad flatcars used to transport container loads with a maximum load capacity of up to 42 tons. In its use, these railroad flatcars are used to transport the cement bags in the pallet arrangement resulting in crack in the bottom frame of the PPCW railroad flatcars structure. The purpose of this analysis is to find out stress value and deformation value that occurred in the railroad flatcars due to the cement bags loading. The analysis process begins with modeling according to the original size of the railroad flatcars which is then followed by providing the support, gravity, loads, and material specifications used. Based on the result of analysis that has been obtained from the load of cement bags of 546,000 N and ratchet lashing of 900,000 N on the frame of PPCW railroad flatcars, we obtained the maximum von Mises stress value of 231.91 MPa arising on the bottom frame of the PPCW railroad flatcars structure as the site of cracking and the maximum total deformation value of 19.526 mm arising in the center of the railroad flatcars. The PPCW railroad flatcars made from SS400 with yield strength value of 245 MPa. Therefore, it was found that the value of stress arising in the railroad flatcars is still in the safe area and is allowed</em><em>.</em><em></em></p>


Author(s):  
Regina Furbino Villefort ◽  
Pedro Jacy Santos Diamantino ◽  
Sandra Lúcia Ventorin von Zeidler ◽  
Alexandre Luiz Souto Borges ◽  
Laís Regiane Silva-Concílio ◽  
...  

Abstract Objective Polymeric framework represent an innovative approach for implant-supported dental prostheses. However, the mechanical response of ultra-high performance polymers as frameworks for full-arch prostheses under the “all-on-four concept” remains unclear. The present study applied finite element analysis to examine the behavior of polyetherketoneketone (PEKK) and polyetheretherketone (PEEK) prosthetic frameworks. Materials and Methods A three-dimensional maxillary model received four axially positioned morse-taper implants, over which a polymeric bar was simulated. The full-arch prosthesis was created from a previously reported database model, and the imported geometries were divided into a mesh composed of nodes and tetrahedral elements in the analysis software. The materials were assumed as isotropic, elastic, and homogeneous, and all contacts were considered bonded. A normal load (500 N magnitude) was applied at the occlusal surface of the first left molar after the model was fixed at the base of the cortical bone. The microstrain and von-Mises stress were selected as criteria for analysis. Results Similarities in the mechanical response were observed in both framework for the peri-implant tissue, as well as for stress generated in the implants (263–264 MPa) and abutments (274–273 MPa). The prosthetic screw and prosthetic base concentrated more stress with PEEK (211 and 58 MPa, respectively) than with PEKK (192 and 49 MPa), while the prosthetic framework showed the opposite behavior (59 MPa for PEEK and 67 MPa for PEKK). Conclusion The main differences related to the mechanical behavior of PEKK and PEEK frameworks for full-arch prostheses under the “all-on-four concept” were reflected in the prosthetic screw and the acrylic base. The superior shock absorbance of PEKK resulted in a lower stress concentration on the prosthetic screw and prosthetic base. This would clinically represent a lower fracture risk on the acrylic base and screw loosening. Conversely, lower stress concentration was observed on PEEK frameworks.


2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Miao Na ◽  
Timothy J. Beavers ◽  
Abhijit Chandra ◽  
Sarah A. Bentil

Abstract Finite element (FE) method has been widely used for gaining insights into the mechanical response of brain tissue during impacts. In this study, a coupled Eulerian−Lagrangian (CEL) formulation is implemented in impact simulations of a head system to overcome the mesh distortion difficulties due to large deformation in the cerebrospinal fluid (CSF) region and provide a biofidelic model of the interaction between the brain and skull. The head system used in our FE model is constructed from the transverse section of the human brain, with CSF modeled by Eulerian elements. Spring connectors are applied to represent the pia-arachnoid connection between the brain and skull. Validations of the CEL formulation and the FE model are performed using the experimental results. The dynamic response of brain tissue under noncontact impacts and the brain regions susceptible to injury are evaluated based on the intracranial pressure (ICP), maximum principal strain (MPS), and von Mises stress. While tracking the critical MPS location on the brain, higher likelihood of contrecoup injury than coup injury is found when sudden brain−skull motion takes place. The accumulation effect of CSF in the ventricle system, under large relative brain−skull motion, is also identified. The FE results show that adding relative angular velocities, to the translational impact model, not only causes a diffuse high strain area, but also cause the temporal lobes to be susceptible to cerebral contusions since the protecting CSF is prone to be squeezed away at the temporal sites due to the head rotations.


2013 ◽  
Vol 677 ◽  
pp. 219-224
Author(s):  
Ying Wu ◽  
Xu Zhou

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.


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