scholarly journals Effect of age-related alterations on the biomechanics of teeth affected by non-carious cervical lesions

2019 ◽  
Vol 22 (2) ◽  
pp. 171-177
Author(s):  
Marina Gullo Augusto ◽  
Tabata Do Prado Sato ◽  
Maria José Domingues De Castro ◽  
Marcia Carneiro Valera ◽  
Alexandre Luis Souto Borges ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Cervical Lesions ◽  
Element Analysis ◽  
Compact Structure ◽  
Age Related ◽  
Occlusal Surfaces ◽  
The Impact

Objective: The prevalence of non-carious cervical lesions (NCCLs) has increased in the recent years, especially in the elderly population. The successful prevention and treatment of those lesions requires an understanding of the biomechanics of aged teeth. Considering the importance of such aspect, the impact of the age-related dentin deposition on the stress distribution of NCCLs was evaluated by means of finite element analysis. Material and Methods: A 2-dimensional model of a sound maxillary first premolar was created using CAD software. Two tooth geometries (sound, aged) and two lesion shapes (wedge, saucer) were simulated to the model. The mesh was built with 35,000 triangle and square elements of 0.1 mm in length. All tissues were considered isotropic, homogeneous and linear. Occlusal surfaces were loaded with 300 N for simulating normal chewing forces. The stress distribution was analyzed by a color scale and by the maximum principal stress at the cavosurface line angle. Results: The aged models presented lower stress concentration in the overall system in comparison to sound models. The sharp angle of wedge shaped lesions promoted higher stress concentration at the center of cavosurface angle, favoring the lesions progression. Conclusion: Considering the limitations of the current methodology, it is possible to conclude that aged tooth is a more compact structure that can better respond to stress loadings. This protective intrinsic mechanism should be considered when adopting preventive and restorative measures for NCCLs for the elderly.KeywordsAging; Finite element analysis; Non-carious; Cervical lesions.

scholarly journals Three-Dimensional Finite Element Analysis of the Veneer—Framework Thickness in an All-Ceramic Implant Supported Fixed Partial Denture

Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 199-207
Author(s):  
Lohitha Kalluri ◽  
Bernard Seale ◽  
Megha Satpathy ◽  
Josephine F. Esquivel-Upshaw ◽  
Yuanyuan Duan
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Distribution ◽  
Three Dimensional ◽  
Ct Scanner ◽  
Element Analysis ◽  
Partial Denture ◽  
Fixed Partial Denture ◽  
Occlusal Surfaces ◽  
All Ceramic

This study was performed as an adjunct to an existing clinical study to validate the effect of veneer: framework thickness ratio on stress distribution in an implant-supported all-ceramic fixed partial denture. Two commercially available titanium dental implants with corresponding customized abutments and a patient-retrieved all-ceramic fixed partial denture were scanned using a high-resolution micro-CT scanner. Reconstructed 3D objects, along with a simulated bone surface, were incorporated into a non-manifold assembly and meshed simultaneously using Simpleware software (Synopsys Simpleware ScanIP Version P-2019.09; Mountain View, CA). Three such volume meshes (Model A, Model B, Model C) corresponding to veneer: framework thickness ratios of 3:1, 1:1, and 1:3 respectively were created, and exported to a finite element analysis software (ABAQUS). An axial load of 110 N was applied uniformly on the occlusal surfaces to calculate the static stresses and contour plots were generated in the post-processing module. From the data obtained, we observed optimum stress distribution in Model B. Also, the tensile stresses were concentrated in the posterior connector region of the prosthesis in all three models tested. Within the limitations of this study, we can conclude that equal thickness of veneer and framework layers would aid in better stress distribution.

Finite-Element Analysis of a Measuring Model for FeAlCrBSiNb Coating Bonding Strength of Revolution Body

2014 ◽  
Vol 577 ◽  
pp. 722-725
Author(s):  
Jia Ying Zhang ◽  
Gang Zhao ◽  
Ye Wang Sun ◽  
Jun Wei Yang ◽  
Huai Bin Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Bonding Strength ◽  
Bonding Interface ◽  
Shearing Stress ◽  
Measuring Process ◽  
Element Analysis

The stress distribution of the coating interface in measuring bonding strength of revolution body coating was emulated. The stress curves of coating bonding interface were obtained. The abscission characteristics of coating were analyzed. It showed that Stress concentration occurred in the symmetric centre of the coating bonding interface. The coating peeled off from the symmetric centre to both sides of the sample interface in the measuring process. Avoiding shearing stress was a method to promote the measuring test of bonding strength of revolution body coating.

Stress Analysis of Grain Steel Silo with Hole

2012 ◽  
Vol 594-597 ◽  
pp. 666-671
Author(s):  
Qi Feng Peng ◽  
Fan Wang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Service Life ◽  
Circular Hole ◽  
Stress Level ◽  
Vertical Displacement ◽  
Principal Strain ◽  
Element Analysis ◽  
The Impact

The stress of the grain steel silo is complex. Recently, many grain silos scraped during their service life. The results of finite element analysis by COMSOL show that the cause of the structure failure is the stress concentration caused by the expanding of the hole. Analysis on different hole on the wall of the silo and different frame to strengthen the hole was also studied. Considering the impact of the weight of the structure, the pressure and friction force caused by the storage of the grain and wind load. The analysis turn out that, if the frame of the hole is identical, the stress level and the first principal strain in condition of circular hole is lower than that of rectangular condition, and the maximum vertical displacement of circular hole is smaller than rectangular. In addition, if the hole is the same, the stress level and the first principal strain in condition of U-shaped frame is lower than that of square condition, but the maximum vertical displacement U-shaped frame is bigger than square frame. Therefore, we can’t reduse the stress level by strenthening the frame.

scholarly journals Effect of Offset Implant Placement on the Stress Distribution Around a Dental Implant: A Three-Dimensional Finite Element Analysis

2015 ◽  
Vol 41 (6) ◽  
pp. 646-651 ◽  
Author(s):  
Hakimeh Siadat ◽  
Shervin Hashemzadeh ◽  
Allahyar Geramy ◽  
Seyed Hossein Bassir ◽  
Marzieh Alikhasi
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Dental Implant ◽  
Three Dimensional ◽  
Element Analysis ◽  
3D Finite Element ◽  
Implant Placement ◽  
Mandibular Molar

There are some anatomical restrictions in which implants are not possible to be inserted in their conventional configuration. Offset placement of implants in relation to the prosthetic unit could be a treatment solution. The aim of this study was to evaluate the effect of the offset placement of implant-supported prosthesis on the stress distribution around a dental implant using 3D finite element analysis. 3D finite element models of implant placement in the position of a mandibular molar with 4 configurations (0, 0.5, 1, 1.5 mm offset) were created in order to investigate resultant stress/strain distribution. A vertical load of 100 N was applied on the center of the crown of the models. The least stress in peri-implant tissue was found in in-line configuration (0 mm offset). Stress concentration in the peri-implant tissue increased by increasing the amount of offset placement. Maximum stress concentration in all models was detected at the neck of the implant. It can be concluded that the offset placement of a single dental implant does not offer biomechanical advantages regarding reducing stress concentration over the in-line implant configuration. It is suggested that the amount of offset should be as minimum as possible.

scholarly journals Influence of non carious cervical lesions depth, loading point application and restoration on stress distribution pattern in lower premolars: a 2D finite element analysis

2015 ◽  
Vol 31 (2) ◽  
pp. 648-656
Author(s):  
Livia Fávaro Zeola ◽  
Fabrícia Araújo Pereira ◽  
Alexia da Mata Galvão ◽  
Tatiana Carvalho Montes ◽  
Sônia Cristina de Sousa ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Distribution ◽  
Distribution Pattern ◽  
Cervical Lesions ◽  
Element Analysis

Stress Distribution in Reverse-Bent Bonded Joint

2012 ◽  
Vol 236-237 ◽  
pp. 48-51
Author(s):  
Yong Tang ◽  
Xiao Cong He ◽  
Jun Chao Zheng ◽  
Kai Zeng ◽  
Yan Fang Ding ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Significant Influence ◽  
Element Analysis ◽  
Joint Performance ◽  
Best Value ◽  
Bonded Joint ◽  
Bonding Technology

Adhesively bonding technology is used increasingly by the automotive and aerospace industries. The design of reverse-bent joint is effective way for improving the bonded joint performance. The influence of preformed angle on the stress distribution of the adhesive-adherend interface is studied in this paper using finite element analysis (FEA). By comparing the results of the FEA for reverse-bent joints with different preformed angle, it can be seen that the preformed angle not only have significant influence on the stress distribution of overlap section, but also changes stress concentration at the spew fillet of bonded joint. The results also indicate that there is a best value of preformed angle in which the reverse-bent bonded joint has the best performance.

Numerical stress analysis for fatigue evaluation of welded tubular T-joints

1993 ◽  
Vol 20 (2) ◽  
pp. 269-286 ◽  
Author(s):  
D. I. Nwosu ◽  
A. S. J. Swamidas ◽  
K. Munaswamy
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Stress Concentration Factor ◽  
Bending Stress ◽  
Element Analysis ◽  
T Joints ◽  
Shell Finite Element ◽  
Good Agreement

The stress distribution along the intersection of offshore tubular T-joints under the action of axial and in-plane and out-of-plane (bending) brace loading has been investigated using degenerated shell elements. The ratios of through-thickness membrane to bending stress and bending to total stress have been obtained using a simple linear interpolation between the stresses on the inner and outer surfaces of the tube. The nominal brace stress and the maximum principal stress values have been used for stress concentration factor determination. The influence of thickness and other geometric parameters on the stress distribution along the intersection was investigated in two ways, viz., increasing the chord thickness while maintaining a constant brace thickness, and keeping the chord thickness constant while reducing the brace thickness.Comparison of the shell finite-element results obtained in this study with the semiloof thin-shell finite-element results of the University College, London (UCL), exhibits good agreement. Good agreement exists between the results of this study and the UCL parametric equations for the chord and the brace of the joint, with a maximum difference of about 7% on the braceside around the saddle position. Comparisons between the finite-element results and other known parametric equations for stress concentration factor with different diametral, wall thickness, and chord thickness and ratios also show good agreement. A comparison of the results obtained from the finite-element analysis and the experimental results of the Canadian Cooperative Fatigue Studies Program, carried out at Memorial University of Newfoundland and University of Waterloo, is also made. Key words: stress distribution, finite-element analysis, stress concentration factors, membrane stress, bending stress, tubular T-joints.

scholarly journals Effect of Base and Inlay Restorative Material on the Stress Distribution and Fracture Resistance of Weakened Premolars

2015 ◽  
Vol 40 (4) ◽  
pp. E158-E166 ◽  
Author(s):  
ACO Souza ◽  
TA Xavier ◽  
JA Platt ◽  
ALS Borges
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Fracture Resistance ◽  
Composite Resin ◽  
Testing Machine ◽  
Control Group ◽  
Element Analysis ◽  
Tooth Structure

SUMMARY The purpose of this study was to evaluate the influence of direct base and indirect inlay materials on stress distribution and fracture resistance of endodontically treated premolars with weakened cusps. Forty healthy human premolars were selected; five were left intact as controls (group C+), and the others were subjected to endodontic treatment and removal of buccal and lingual cusp dentin. Five teeth were left as negative controls (group C−). The remaining 30 teeth were divided into two groups according to the direct base material (glass ionomer [GIC] or composite resin [CR]). After base placement, each group was subjected to extensive inlay preparation, and then three subgroups were created (n=5): no inlay restoration (GIC and CR), restored with an indirect composite resin inlay (GIC+IR and CR+IR), and restored with a ceramic inlay (GIC+C and CR+C). Each specimen was loaded until fracture in a universal testing machine. For finite element analysis, the results showed that the removal of tooth structure significantly affected fracture resistance. The lowest values were presented by the negative control group, followed by the restored and based groups (not statistically different from each other) and all lower than the positive control group. In finite element analysis, the stress concentration was lower in the restored tooth compared to the tooth without restoration, whereas in the restored teeth, the stress concentration was similar, regardless of the material used for the base or restoration. It can be concluded that the inlay materials combined with a base showed similar behavior and were not able to regain the strength of intact tooth structure.

scholarly journals Influence of Preparation Design, Restorative Material and Load Direction on The Stress Distribution of Ceramic Veneer in Upper Central Incisor

2021 ◽  
Vol 24 (3) ◽  
Author(s):  
Laura Célia Fernandes Meirelles ◽  
Fernanda Zapater Pierre ◽  
João Paulo Mendes Tribst ◽  
Clovis Pagani ◽  
Eduardo Bresciani ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Stress Distribution ◽  
Lithium Disilicate ◽  
Occlusal Plane ◽  
Central Incisor ◽  
Stress Concentrations ◽  
Element Analysis ◽  
Preparation Design

Objective: Evaluate the effect of four preparation designs, two ceramic materials, and two occlusion contact types on the stress distribution of ceramic veneer in upper central incisor. Material and methods:  3D-models were performed in the modeling software containing enamel, dentin, pulp, periodontal ligament and a base of polyurethane resin. The designs were modeled and exported to the computer aided engineering software to perform the static structural analysis. For the mesh, a total of 155429 tetrahedron elements and 271683 nodes were used, after a 10% convergence test. Two materials, lithium disilicate and feldspathic ceramics, were simulated. A static load of 100 N on 45º was applied on the incisal and middle thirds of the palatal tooth region, guided by the occlusal plane. The base was constrained in all directions. The Maximum Principal Stress was the failure criteria chosen for the analysis. Results: The Finite Element Analysis showed that the most conservative designs presented less stress concentration on the ceramic veneer. However, the highest tensile stress concentrations were observed on lithium disilicate veneer with extend design, on the middle third. The type of occlusal contact presented different stress patterns among the preparation designs; the incisal contact showed higher stress concentration compared to middle third contact regardless the ceramic material. Conclusions: To perform a ceramic veneer in upper central incisor, the feldspathic ceramic presented promising results and should be recommended when the extended design was done. Regarding contact types, the incisal contact is more prone to failure regardless the ceramic and preparation design.   Keywords Ceramics; Dental veneers; Finite element analysis.

Sign in / Sign up

Export Citation Format

Share Document