Download or read book Finite Element Stress Analysis on the Effect of an Implant Alignment Offset and Load Direction in the Posterior Mandible written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Background;Slight offset of the central implant in 3-unit implant-supported prostheses has been recommended to improve biomechanical behavior.However, studies that assessed the effects of an offset implant congfiguration in the posterior mandible are rare.Aim/Hypothesis;The purpose of this 3-dimensional (3D) finite element study was to assess the effects of load direction and number of implant in 3-unitimplant-supported prostheses with varying implant positions (straight-line or offset) on the stress distribution in the implant,prosthesis, and bone tissue.Materials and Methods;Three 3D models were used to simulate a posterior mandible bone block: 2 implants and 3-unit fixed dental prosthesis(FDP) with apontic in the middle (model M1), 2 implants and 3-unit FDP with a cantilever pontic at one end (model M2), FDP supported by 3implant with straight line placement (model M3) and FDP supported by 3 implant with staggered implant configuration (model M4).The applied forces were 120 N axially (L1), or 120 N obliquely(L2). The type of implant platform simulated was an external hexagon.Maximum von Mises stress (VMS) on the fixture, abutment, screws, fixed prosthesis and supporting alveolar bone was measured andanalyzed.Results;Peak VMS in the implants by oblique loading were 10-25 times greater in implant and 6-12 times greater in alveolar bone,respectively than the stresses by axial loading.Compared to the maximum stress value of the implant by oblique loading in model M1, the maximum stress value increased to 116%in M2, but decreased to 74% and 71% in M3 and M4, respectively.In the cantilevered M2 model, the maximum stress values in the FDP were 851.5 and 908.4 MPa, respectively, by the vertical andoblique loadings, which are 5.1 and 7.1 times higher than the other models, respectively.The area of maximum stress in the implant was located around the area where the abutment screw and fixture were connected.Stress concentration was observed at an abutment screw by oblique load and at the top of the implant fixture by axial load.In the supporting bone, the maximum stress value increased to 120% in M2, but decreased to 69% and 63% in M3 and M4,compared to the stress in M1 by oblique load.Conclusions and Clinical Implications;The effect of staggered alignment on implant stress was negligible, but the cantilever design of the prosthesis and the number ofimplants had a greater impact on stress distrubution.

Download or read book A Finite Element Analysis of the Stress Distribution of an Osseointegrated Implant written by Aisling M. O'Mahony and published by . This book was released on 1997 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: The maintenance of the osseointegrated implant bone interface is critical to the success of the osseointegrated implant. Many clinical studies have suggested that repeatedly excessive loads applied to the implant restoration, is one of the factors contributing to breakdown at the implant/bone interface and premature failures of the osseointegrated implant. In the single unit osseointegrated implant in the posterior mandible the mesiodistal and buccolingual widths of the crown are generally greater than the width of the implant fixture. The point of load application is one of the variables that influences the manner in which occlusal forces are transmitted to the implant and surrounding bone. Off axis loads applied to the crown create a cantilever effect and introduce bending moments which may cause excessive stresses at the implant bone interface. The wider the crown, the greater the potential for off axis loading. The purpose of this study was to evaluate and compare the effect of axial and off axis loads on the stress gradients at the oxxeointegrated implant/bone interface of a single unit posterior implant. Finite element analysis was used to evaluate the magnitude and location of stresses. Occlusal forces were modeled as axial and off axis vertical loading. The study showed that under load conditions the highest stresses were concentrated at the apex of the implant and at the crestal bone/implant interface. Off axis loading resulted in a large increase in compressive stresses in the crestal cortical bone on the side of the applied load, and a large increase in tensile stresses in the crestal cortical bone on the side opposite the applied load.

Download or read book Application of the Finite Element Method in Implant Dentistry written by Jianping Geng and published by Springer Science & Business Media. This book was released on 2008-09-26 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book creates the theoretical foundation that novices need to perform the finite element method in implant dentistry. It shows how both the implant dentist and the designer can benefit from finite element analysis. The authors explain the theory and math of the finite element method. Then, you get practical applications alongside discussions of the critical issues in using finite element analysis for dental implant design.

Download or read book Three dimensional Finite Element Analysis of Internal Conical Joint Implant supported Fixed Prostheses in the Posterior Maxilla written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There are various implant placement options, such as using a short implant or changing the direction of the implant placement to use more residual bone. Currently, the connection design between implant fixture and the abutment is in two forms: external hex type and internal conical type. The biomechanical information on the various implant systems and various implant placement option is not sufficient to determine reliable treatment plans and implant choices.This study aimed to compare the functional stresses generated in the internal conical joint implant, prosthesis and supporting bone in the posterior maxilla, using finite element method.Two internal joint type implant (u00d85 X 7mm, u00d85 X 13mm) with TS2 SA fixture design of Osstem (Seoul, Korea) were modeled by computer-aided design software (Solidwork 2018). The posterior maxillary bone and 3-unit all zirconia crowns were also simulated. Three different scenarios were modeled with various implant alignment (SI3; 3 unit fixed prosthesis on 3 short implant abutments, SI2; 3 unit fixed prosthesis on 2 short (7mm) implant abutments, AI2; 3 unit fixed prosthesis on 1 short implant abutment and 1 long (13mm) implant with an angled abutment). A load of 30 N was applied vertically and obliquely, respectively to each of 12 occlusal contact points of the crown.The maximum Mises stresses produced by oblique loading was observed near the connection interfaces of the abutment. The peak value was 430 MPa for SI3, 568 MPa for SI2 and 656 MPa for AI2 respectively. There was no significant difference in peak von Mises stress between models due to vertical loading. The maximum compressive stresses due to oblique load on the supporting bone adjacent to the implant were 145 MPa for SI3, 204 MPa for SI2 and 200 MPa for AI2, respectively.Internal joint type design of implant concentrated the stresses to the conical interface between fixture and abutment interface, demonstrating the wedge effect between them. Increasing the number of implants was the most effective contributing factor to reduce the stresses in the internal conical joint implant and supporting bone in our study models.

Download or read book Biomechanics in Dentistry Evaluation of Different Surgical Approaches to Treat Atrophic Maxilla Patients written by Muhammad Ikman Ishak and published by Springer Science & Business Media. This book was released on 2012-08-31 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book shows computational finite element simulations to analyse the strength of implant anchorage for intrasinus and extramaxillary approaches under various occlusal loading locations and directions. Three-dimensional model of the craniofacial area surrounding the region of interest, soft tissue and framework are developed using computed tomography image datasets. The zygomatic and standard dental implants are modeled using a conventional computer-aided design software and placed at the appropriate location. Material properties are assigned appropriately for the cortical, cancellous bones and implants with Masseter forces applied at the zygomatic arch and occlusal loadings applied on the framework surface.

Download or read book Structural Analysis of an Osseointegrated Dental Implant System written by M. Jane Morgan and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1997 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Distribution of External Hex Joint Implant supported Fixed Prostheses in the Posterior Maxilla 3 D Finite Element Analysis written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: If the bone graft is not performed in the atrophied posterior maxilla, there are various implant placement options, such as using a short implant or changing the direction of the implant placement to use more residual bone. Biomechanical information regarding different implant systems and different implant placement options is not sufficient to determine a reliable treatment plan and implant selection. The purpose of this study was to analyze functional stresses generated in the external hex joint implant, prosthesis and supporting bone in the posterior maxilla using finite element method. Two external hex type implant (u00d85 X 7mm, u00d85 X 13mm) with the design of the US3 SA fixture of Osstem (Seoul, Korea) were modeled by computer-aided design software (Solidwork 2018). The posterior maxillary bone and 3-unit all zirconia crowns were also simulated. Three different scenarios were modeled with various implant alignment (S3E; 3 unit fixed prosthesis on 3 short implant abutments, S2E; 3 unit fixed prosthesis on 2 short (7mm) implant abutments, A2E; 3 unit fixed prosthesis on 1 short implant abutment and 1 long (13mm) implant with an angled abutment). A load of 30 N was applied vertically and obliquely, respectively to each of 12 occlusal contact points of the crown. Regardless of load direction, the highest von Mises stresses of the implants and prosthesis occurred in the screw tightening contact area of the external hex abutment. The values of maximum von Mises stresses due to vertical load were similar between each model. The values ranged from 250 MPa to 270 MPa. The maximum von Mises stresses produced by oblique load at the abutment were 277, 283, and 317MPa for the A2E, S3E, and S2E models, respectively. The maximum compressive stresses due to the oblique load on the marginal bone adjacent to the implant was 224 MPa in S3E, 342 MPa in A2E, and 362 MPa in S2E, respectively. Externally connection design of implant showed well-distributed stress around all components of the implant system. The maximum stresses generated in the implant was within the yield strength limit of the material. A 3-unit fixed bridge with 2 short implants (Model S2E) generated the largest compressive stresses around the bone adjacent to the external hex type implant.

Download or read book Three dimensional Finite Element Analysis of Mandibular Overdentures Supported by Mini implants written by Scully, Jessica Scully and published by . This book was released on 2017 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examined the effect of using two anterior denture-supporting mini implants (mIMP2) compared to four (two anterior and two posterior) denture-supporting mini-implants (mIMP4) on the stress experienced by the mini-implants and the strain experienced by the peri-implant and analogous posterior bone. The stress and strain values were also compared to known values of strength for the mini-implants and physiologic strain values. Finite element modeling was used to study the effects. Two models were created identically, with the exception of the number of denture-supporting mini-implants used, and contained modeled mucosa, cortical bone, cancellous bone, and the mini-implants. The models were loaded over one second with three 70N loads bilaterally and results with collected using a PostView program. The anterior mini-implants in both models showed stresses that would not put them at risk for fracture. The posterior mini-implants in mIMP4 experienced stresses above their yield point, indicating that they could be at risk for fracture. Strain in the peri-implant bone anteriorly and the posterior bone in mIMP2 was in the physiologic range. The posterior peri implant bone in mIMP4 showed strains that were above physiologic, which indicates this region could be at risk for bone resorption. Based on the limitations of this study, posterior mini-implants and posterior peri implant bone could be at risk for fracture and pathologic resorption. Dentists must weigh the risks and benefits of using mini-implants to support overdentures in each clinical case to determine if the treatment could be successful in light of the potential negative consequences.

Download or read book Stress Analysis of Dental Implant Devices and Human Mandible by Finite Element Method written by Tong Zhang and published by . This book was released on 1992 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Photoelastic Stress Analysis of the Bone Supporting a Dental Endosteal Implant written by Ronald A. Yapp and published by . This book was released on 1977 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Reverse Torque Effect on Bone Stress Levels in Peri implantitis Defects Finite Element Analysis written by Deniz Cetiner and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Different treatment options can be applied in the presence of advanced bone loss around implants. It is known that the use of reversetorque is a minimally invasive, time-saving and inexpensive technique for the removal of implant. It is not known whether the stressesthat occur when removal torque force is applied, where the tolerance of the bone exceeds, and whether there is any damaged bonetissue due to the formation of micro-fractures in the bone-implant connection.The aim of this study was to investigate the effect of the reverse torque force on the stress distribution around bone surface inperi-implantitis bone defect by using 3D finite-element analysis.Four different design implants were placed in the maxillary and mandibular posterior area modeled by varying the elastic modulus forcancellous and cortical bone. A total of 32 models were obtained by creating around of each implant 3 different peri-implantitis defectsand control group which is none defect around implant. Axial 10 Ncm removal torque force was applied to the occlusal node at thecenter of implants. The results were analyzed using maps of maximum principal, minimum principles and Von Mises stresses, and distributions.As a result of the analysis of different models; implant design, presence and variety of bone defects, and all bone type factors affectedthe torque force required to remove the implant. In the peri-implantitis models where the implant-bone contact is greater, the removaltorque force and stress distribution were increased than other models. The differences in implant geometry affected the reversetorque force and had different stress distributions. According to the results of our study, stress distributions are concentrated incortical bone compared to cancellous bone.Since the results obtained in our study consist of mathematical examination of models, it gives information about certain conditionsabout general mechanism and materials. However, it is possible to have knowledge in natural and biological conditions in clinicalapplications. Therefore, although some results can be obtained as a result of the data obtained from analytical studies, further clinical studies are needed to evaluate these conditions.

Download or read book Immediate Loading of Endosseous Implants in the Posterior Mandible written by Georgios Romanos and published by . This book was released on 2005 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Romanos (implant dentistry, University of New York) details the conditions necessary for successful immediate loading of implants in the posterior area of the mandible, so that this therapeutic concept can be implemented in daily practice. An introductory chapter examines the roles of implant material, surface morphology, and implant form in osseoi

Download or read book Finite Element Analysis of Dental Implant bone System During and After Implantation written by Rudi Cobus Van Staden and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : Development of an ideal substitute for missing teeth has been a major aim of dental practitioners for millennia. Modern dental implants are biocompatible screw-like titanium {u2018}fixtures{u2019} that are surgically placed into the jaws to replace missing teeth. Implants are superior to conventional prostheses, in both function and long-term predictability. In 2006 approximately 30,000 implants were placed in Australian patients. Implant sales have doubled in the last 5 years and are increasing by about 15% per year. Although implants exhibit excellent long-term retention (~95% after 5 years), there are significantly more failures in areas where bone quality and quantity is poor, resulting in poor patient outcomes and costs estimated at $15 million per year in Australia. Most failures arise from poor clinical technique and inadequate understanding of the potentially damaging stress characteristics during implant placement and function (chewing). Three-dimensional (3D) Finite Element Analysis (FEA) is a numerical method for analysing stresses and deformations in structures of any given geometry and under any load. There are reports on utilising 3D FEA to investigate implant-jawbone interactions after full osseointegration. However no work has been done to comprehensively quantify the performance of the bone-implant system during and after implantation. This research thus aims to develop a comprehensive FEA technique to evaluate the performance of the bone-implant system during the implantation process itself, as well as the healing and maintenance phases of osseointegration.

Download or read book Finite Element Stress Analysis of Bone Surrounding Osseointegrated Dental Implants written by Marianne Ierace Mayberry and published by . This book was released on 1987 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of the Finite Element Method in Implant Dentistry written by 耿建平 and published by . This book was released on 2008 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part of the new series, Advanced Topics in Science and Technology in China, this book is designed to give the necessary theoretical foundation to new users of the finite element method in implant dentistry, and show how both the implant dentist and designer can benefit from finite element analysis. The first part deals with the theory of the finite element method. containing the necessary mathematical theory but written so that readers from a dental background can easily understand. Then basic knowledge of implant dentistry is introduced to readers from an engineering background. Next, dental.

Download or read book A Three dimensional Finite Element Stress Analysis in and Around the Isis Endosseous Dental Implant written by Robert J. Seckinger and published by . This book was released on 1989 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Combination Stress Analysis of Immediate Implant Provisional Restoration Using Cyclic Fatigue Test and Three dimensional Finite Element Analysis written by Kikue Yamaguchi and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Objective: In recent years, immediate loading implant treatment has been widely recognized as an effective solution for edentulous patients. Risk factors of disintegration associated with immediate loading include excessive occlusal force such as bruxism, and relating to the technical complication, the fracture of temporary restoration has been pointed out. The fracture of temporary restoration can be considered to increase the micro movement around implant, and lead to fail osseointegration. A large numbers of stress analysis for implant prosthesis has been reported by 3D FEA and mechanical tests, but it has not been clarified the cause of fracture of the temporary restoration in multidimensional analysis. In this study, we analyzed the stress concentration in patient models by 3D FEA and the cyclic fatigue test in materials for temporary restoration, and tried out the combination stress analysis. Subjects and Methods: The strength to be possessed as a temporary prosthesis was examined by 1) the stress test, 2) the three-point bending test and 3) the three-dimensional finite element analysis (FEA). 1) For the 100000 cyclic fatigue test, a test piece of 25 mm in length u00d7 10 mm in width u00d7 2 mm in thickness cut out from a resin disc for CAD/CAM (Aadva PMMA disc, GC Co.) was used. 2) For the three-point bending test, a similar test piece to the one used in the stress test was used. 3) For the FEA, the results of the three-point bending test was reproduced and analyzed. Test pieces were similar condition. 4) To recognize the clinical situation, another FEA was done with the immediate load patient model. These models were maxillary edentulous patients before implant placement. To assume immediate load, the inter-face between the bone and the implant was set as a u201ccontact stateu201d (frictional coefficient = 0.33). The physical property values of the bone were calculated from the CT values and set for each element, and the physical property values of other elements were set based on the known values. The load condition was set based on the occlusal force data recorded from a patient with bruxism, and the constraint condition was set as the maxillary sinus upper margin. This study was approved by the ethics committee of our school of dentistry and the data was used with the patientu2019s consent.Results: From the 105 cyclic fatigue test, it is revealed that the PMMA piece was fractured over 115 N load. In the three-point bending test, the average maximum tensile stress in the test piece was 80.3 MPa at 115 N load, that of FEA analysis was 75.5 MPa at the same condition. In the FEA patient models, the maximum tensile stress over 75.5 MPa was found at the PMMA material around temporary cylinder, and maximum value were 247.7 MPa, 258.8 MPa and 290.8MPa for each patient.Discussion and Conclusion: The fracture of temporary restoration in immediate loading treatment is estimated to occur around temporary cylinders. It is necessary to consider temporary restoration designs or reinforcement not to exceed the maximum tensile stress in real clinical situation. From the results of this study, it is suggested that the effective possibility of combination stress analysis in real material and FEA model.