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 Atlas of Oral Implantology written by Pankaj P. Singh and published by Elsevier Health Sciences. This book was released on 2009-12-01 with total page 539 pages. Available in PDF, EPUB and Kindle. Book excerpt: With more than 1,500 illustrations, this edition covers key topics including diagnosis and planning, basic implant surgery, advanced implant surgery, implant prosthodontics, and implant management. Also includes important information on observing and diagnosing patients.
Download or read book Finite Element Analysis of Orthopaedic Plates and Screws to Reduce the Effects of Stress Shielding written by Kristina Haase and published by . This book was released on 2009 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Skeletal Anchorage in Orthodontic Treatment of Class II Malocclusion E Book written by Moschos A. Papadopoulos and published by Elsevier Health Sciences. This book was released on 2014-09-29 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book offers a comprehensive and critical review which presents not only the principles and techniques involved in the use of skeletal anchorage techniques and devices (such as orthodontic implants, miniscrew implants and mini plates), but also the scientific evidence available regarding the use of these contemporary applications and their clinical efficacy. • Provides an introduction to the conventional and noncompliance treatment of Class II malocclusion • Provides an introduction to the use of skeletal anchorage reinforcement approaches in orthodontics • Outlines the clinical considerations required for the use of skeletal anchorage devices in orthodontics • Explains the insertion and removal procedures of orthodontic implants, miniscrew implants and mini plates • Discusses the use of orthodontic implants for the treatment of Class II malocclusion • Explains the use of mini plates and zygomatic anchorage for the treatment of Class II malocclusion • Discusses the use of mini-screw implants for the treatment of Class II malocclusion • Explains the use of skeletal anchorage reinforcement of the noncompliance devices used for the treatment of Class II malocclusion • Explores the efficiency of skeletal anchorage and its risk management
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1995 with total page 1576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Cancellous Bone written by Ardiyansyah Syahrom and published by Springer. This book was released on 2017-08-05 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides comprehensive mechanobiological insights into bone, including the microstructure of cancellous bone and its realistic loading in the human body. This approach considers different types of loads, i.e. static and dynamic, and the response under uniaxial and multiaxial loading conditions. The book also reviews additional factors influencing biomechanical properties, e.g. fluid transport. In closing, the mechanobiological approach is discussed in the context of the finite element method.
Download or read book Investigation of Bone Modeling and Remodeling at a Loaded Bone implant Interface written by Susan Joy Hoshaw and published by . This book was released on 1992 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 Multi axial Fatigue of Trabecular Bone with Respect to Normal Walking written by Mohammad Mostakhdemin and published by Springer. This book was released on 2015-06-10 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the analysis and treatment of osteoporotic bone based on drug administration, tracking fatigue behavior and taking into consideration the mechanical interaction of implants with trabecular bone. Weak trabeculae are one of the most important clinical features that need to be addressed in order to prevent hip joint fractures.
Download or read book Effects of Implant Thread Geometry on Strength of Osseointegration and the Bone implant Interface written by Jennifer Thompson Steigenga and published by . This book was released on 2002 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Finite Element Simulation of the Bone Modeling and Remodeling Processes Around a Dental Implant written by Qiguo Rong and published by . This book was released on 2002 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Finite Element Analysis of the Stress on the Implant Bone Interface of Dental Implants with Different Structures written by Liangjian Chen and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Finite Element Analysis of the Stress on the Implant-Bone Interface of Dental Implants with Different Structures.
Download or read book Mechanical Testing of Orthopaedic Implants written by Elizabeth Friis and published by Woodhead Publishing. This book was released on 2017-05-24 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanical Testing of Orthopaedic Implants provides readers with a thorough overview of the fundamentals of orthopedic implants and various methods of mechanical testing. Historical aspects are presented, along with case studies that are particularly useful for readers. - Presents information on a range of implants, from dental to spinal implants - Includes case studies throughout that help the reader understand how the content of the book is applied in practice - Provides coverage and guidance on FDA regulations and requirements - Focuses on application of mechanical testing methods
Download or read book Plasticity written by S. Nemat-Nasser and published by Cambridge University Press. This book was released on 2004-11-29 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher Description
Download or read book Aseptic Loosening of Orthopedic Implants written by Mehdi Amirhosseini and published by Linköping University Electronic Press. This book was released on 2019-05-24 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aseptic loosening is the main cause of failure of orthopedic prostheses. With no pharmaceuticals to prevent or mitigate periprosthetic bone degradation, a surgery to replace the loose implant with a new one is the only choice to restore patients’ function. Most studies on mechanisms for aseptic loosening investigate wear debris particle-induced osteolysis. However, pathological loading conditions around unstable implants can also trigger osteoclast differentiation and bone loss. In the first study, global gene expression changes induced by mechanical instability of implants, and by titanium particles were compared in a validated rat model for aseptic loosening. Microarray analysis showed that similar signaling pathways and gene expression patterns are involved in particle- and instability-induced periprosthetic osteolysis with an early onset innate immune response as a hallmark of osteolysis induced by mechanical instability. Further, effects of potential therapeutics on restriction of excessive osteoclast differentiation were evaluated. Wnt signaling pathway is known to regulate bone remodeling. In the second study, effects of inactivation of glycogen synthase kinase 3 beta (GSK-3?), a negative regulator of canonical Wnt signaling, on instability-induced periprosthetic osteolysis were examined using our rat model for aseptic loosening. Inhibition of GSK-3? led to a decrease in osteoclast numbers in the periprosthetic bone tissue exposed to mechanical instability while osteoblast perimeter showed an increase. This was accompanied by higher bone volume fraction (BV/TV) in animals treated with the GSK-3? inhibitor. In the third study, potential beneficial effects of two selective inhibitors of cyclindependent kinase 8/19 (CDK8/19) on bone tissue were evaluated. CDK8/19 is a Mediator complex-associated transcriptional regulator involved in several signaling pathways. CDK8/19 inhibitors, mainly under investigation as treatments for tumors, are reported to enhance osteoblast differentiation and bone formation. We show in this study, for the first time, that inhibition of CDK8/19 led to marked suppression of osteoclast differentiation from bone marrow macrophages in vitro through disruption of the RANK signaling. In mouse primary osteoblasts downregulation of osteopontin mRNA, a negative regulator of mineralization, together with increased alkaline phosphatase activity and calcium deposition indicated that osteoblast mineralization was promoted by CDK8/19 inhibition. Moreover, local administration of a CDK8/19 inhibitor promoted cancellous bone regeneration in a rat model for bone healing. These studies contribute to better understanding of mechanisms behind mechanical instability-induced periprosthetic osteolysis and propose potential therapeutics to restrict bone loss with effects on both osteoclasts and osteoblasts.
