1
|
Deste Gökay G, Gökçimen G, Oyar P, Durkan R. Comparison of fatigue lifetime of new generation CAD/CAM crown materials on zirconia and titanium abutments in implant-supported crowns: a 3D finite element analysis. BIOMED ENG-BIOMED TE 2024; 0:bmt-2024-0017. [PMID: 38997228 DOI: 10.1515/bmt-2024-0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 07/04/2024] [Indexed: 07/14/2024]
Abstract
OBJECTIVES Due to the dynamic character of the stomatognathic system, fatigue life experiments simulating the cyclic loading experienced by implant-supported restorations are critical consideration. The aim of this study was to examine the effect of different crown and abutment materials on fatigue failure of single implant-supported crowns. METHODS Models were created for 10 different designs of implant-supported single crowns including two zirconia-reinforced lithium silicates (crystallized and precrystallized), monolithic lithium disilicate, polymer-infiltrated ceramic networks, and polyetheretherketone supported by zirconia and titanium abutments. A cyclic load of 179 N with a frequency of 1 Hz was applied on palatal cusp of a maxillary first premolar at a 30° angle in a buccolingual direction. RESULTS In the models with titanium abutments, the polymer-infiltrated ceramic network model had a lower number of cycles to fatigue failure values in the implant (5.07), abutment (2.30), and screw (1.07) compared to others. In the models with zirconia abutments, the crystallized zirconia-reinforced lithium silicate model had a higher number of cycles to fatigue failure values in the abutment (8.52) compared to others. Depending on the fatigue criteria, polyetheretherketone implant crown could fail in less than five year while the other implant crowns exhibits an infinite life on all models. CONCLUSIONS The type of abutment material had an effect on the number of cycles to fatigue failure values for implants, abutments, and screws, but had no effect on crown materials. The zirconia abutment proved longer fatigue lifetime, and should thus be considered for implant-supported single crowns.
Collapse
Affiliation(s)
- Gonca Deste Gökay
- Faculty of Dentistry, Department of Prosthodontics, 105810 Bursa Uludağ University , Bursa, Türkiye
| | - Gülsüm Gökçimen
- Department of Prosthodontics, Ankara 75th year Oral and Dental Health Hospital, Ankara, Türkiye
| | - Perihan Oyar
- School of Health Services, Dental Prosthetics Technology, Hacettepe University, Ankara, Türkiye
| | - Rukiye Durkan
- Faculty of Dentistry, Department of Prosthodontics, Istanbul Okan University, Istanbul, Türkiye
| |
Collapse
|
2
|
De Stefano M, Lanza A, Sbordone L, Ruggiero A. Stress-strain and fatigue life numerical evaluation of two different dental implants considering isotropic and anisotropic human jaw. Proc Inst Mech Eng H 2023; 237:1190-1201. [PMID: 37667892 DOI: 10.1177/09544119231193879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
Dental prostheses are currently a valid solution for replacing potential missing tooth or edentulism clinical condition. Nevertheless, the oral cavity is a dynamic and complex system: occlusal loads, external agents, or other unpleasant events can impact on implants functionality and stability causing a future revision surgery. One of the failure origins is certainly the dynamic loading originated from daily oral activities like eating, chewing, and so on. The aim of this paper was to evaluate, by a numerical analysis based on Finite Elements Method (FEM), and to discuss in a comparative way, firstly, the stress-strain of two different adopted dental implants and, subsequently, their fatigue life according to common standard of calculations. For this investigation, the jawbone was modeled accounting for either isotropic or anisotropic behavior. It was composed of cortical and cancellous regions, considering it completely osseointegrated with the implants. The impact of implants' fixture design, loading conditions, and their effect on the mandible bone was finally investigated, on the basis of the achieved numerical results. Lastly, the life cycle of the investigated implants was estimated according to the well-established theories of Goodman, Soderberg, and Gerber by exploiting the outcomes obtained by the numerical simulations, providing interesting conclusions useful in the dental practice.
Collapse
Affiliation(s)
- Marco De Stefano
- Department of Industrial Engineering, University of Salerno, Fisciano, Italy
| | - Antonio Lanza
- Department of Medicine, Surgery and Dentistry "Schola Medica Salernitana," University of Salerno, Baronissi, Italy
| | - Ludovico Sbordone
- Department of Medicine and Health Sciences, University of Molise, V Campobasso, Italy
| | - Alessandro Ruggiero
- Department of Industrial Engineering, University of Salerno, Fisciano, Italy
| |
Collapse
|
3
|
Hernandez BA, Freitas JP, Capello Sousa EA. Fatigue life estimation of dental implants using a combination of the finite element method and traditional fatigue criteria. Proc Inst Mech Eng H 2023; 237:975-984. [PMID: 37458260 DOI: 10.1177/09544119231186097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
Abstract
Failure by fatigue can be sudden and catastrophic. Therefore, ensuring that dental implants, which are under constant cyclic loading, do not fail to fatigue is imperative. The majority of the studies about the topic only performed in vitro tests, which are expensive and time-consuming. The Finite Element (FE) method is less costly and it allows the simulation of several different loading scenarios. Nonetheless, there are only a few studies analysing fatigue in dental prostheses using FE models, and the few available did not include all the relevant parameters, such as geometry effect, surface finishing, etc. Therefore, this study aimed to analyse the fatigue behaviour of a single-unit dental implant with two screws using a combination of the numerical results and the traditional fatigue criteria - a combination that was not yet fully and correctly explored. A finite element model comprising a single implant, one abutment, one abutment screw, one fixation screw and one prosthetic crown was developed. Material properties were assigned based on literature data. A 100 N load was applied to mimic the mastication forces and fatigue analysis was conducted using the Gerber, Goodman and Soderberg fatigue criteria. The fatigue analysis demonstrated that the abutment screw could fail in less than 1 year, depending on the criteria, while the fixation screw exhibits an infinite life. The results illustrated the importance of analysing the fatigue behaviour of dental implants and highlighted the potential of finite element models to simulate the biomechanical behaviour of dental implants.
Collapse
Affiliation(s)
- Bruno A Hernandez
- Department of Mechanics, Centre for Simulation in Bioengineering, Biomechanics and Biomaterials (CS3B), School of Engineering, Campus of Guaratinguetá, São Paulo State University (UNESP), Guaratinguetá, São Paulo State, Brazil
| | - João Po Freitas
- Department of Mechanical Engineering, Centre for Simulation in Bioengineering, Biomechanics and Biomaterials (CS3B), School of Engineering, Campus of Bauru, São Paulo State University (UNESP), Bauru, São Paulo State, Brazil
| | - Edson A Capello Sousa
- Department of Mechanical Engineering, Centre for Simulation in Bioengineering, Biomechanics and Biomaterials (CS3B), School of Engineering, Campus of Bauru, São Paulo State University (UNESP), Bauru, São Paulo State, Brazil
| |
Collapse
|
4
|
Kazarinov N, Stotskiy A, Polyakov A, Valiev RZ, Enikeev N. Finite Element Modeling for Virtual Design to Miniaturize Medical Implants Manufactured of Nanostructured Titanium with Enhanced Mechanical Performance. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7417. [PMID: 36363009 PMCID: PMC9658747 DOI: 10.3390/ma15217417] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/16/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
The study is aimed to virtually miniaturize medical implants produced of the biocompatible Ti with improved mechanical performance. The results on the simulation-driven design of medical implants fabricated of nanostructured commercially pure Ti with significantly enhanced mechanical properties are presented. The microstructure of initially coarse-grained Ti has been refined to ultrafine grain size by severe plastic deformation. The ultrafine-grained (UFG) Ti exhibits remarkably high static and cyclic strength, allowing to design new dental and surgical implants with miniaturized geometry. The possibilities to reduce the implant dimensions via virtual fatigue tests for the digital twins of two particular medical devices (a dental implant and a maxillofacial surgery plate) are explored with the help of finite element modeling. Additionally, the effect of variation in loading direction and the fixation methods for the tested implants are studied in order to investigate the sensitivity of the fatigue test results to the testing conditions. It is shown that the UFG materials are promising for the design of a new generation of medical products.
Collapse
Affiliation(s)
- Nikita Kazarinov
- Institute of Problems of Mechanical Engineering, 199178 St. Petersburg, Russia
- Dynamics and Extreme Characteristics of Promising Nanostructured Materials, Saint Petersburg State University, 199034 St. Petersburg, Russia
| | - Andrey Stotskiy
- Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, K. Marx 12, 450008 Ufa, Russia
- Laboratory of Multifunctional Materials, Bashkir State University, 450076 Ufa, Russia
| | - Alexander Polyakov
- Laboratory of Multifunctional Materials, Bashkir State University, 450076 Ufa, Russia
| | - Ruslan Z. Valiev
- Dynamics and Extreme Characteristics of Promising Nanostructured Materials, Saint Petersburg State University, 199034 St. Petersburg, Russia
- Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, K. Marx 12, 450008 Ufa, Russia
| | - Nariman Enikeev
- Dynamics and Extreme Characteristics of Promising Nanostructured Materials, Saint Petersburg State University, 199034 St. Petersburg, Russia
- Center for Design of Functional Materials, Bashkir State University, 450076 Ufa, Russia
| |
Collapse
|
5
|
Davoodi E, Montazerian H, Mirhakimi AS, Zhianmanesh M, Ibhadode O, Shahabad SI, Esmaeilizadeh R, Sarikhani E, Toorandaz S, Sarabi SA, Nasiri R, Zhu Y, Kadkhodapour J, Li B, Khademhosseini A, Toyserkani E. Additively manufactured metallic biomaterials. Bioact Mater 2022; 15:214-249. [PMID: 35386359 PMCID: PMC8941217 DOI: 10.1016/j.bioactmat.2021.12.027] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 02/06/2023] Open
Abstract
Metal additive manufacturing (AM) has led to an evolution in the design and fabrication of hard tissue substitutes, enabling personalized implants to address each patient's specific needs. In addition, internal pore architectures integrated within additively manufactured scaffolds, have provided an opportunity to further develop and engineer functional implants for better tissue integration, and long-term durability. In this review, the latest advances in different aspects of the design and manufacturing of additively manufactured metallic biomaterials are highlighted. After introducing metal AM processes, biocompatible metals adapted for integration with AM machines are presented. Then, we elaborate on the tools and approaches undertaken for the design of porous scaffold with engineered internal architecture including, topology optimization techniques, as well as unit cell patterns based on lattice networks, and triply periodic minimal surface. Here, the new possibilities brought by the functionally gradient porous structures to meet the conflicting scaffold design requirements are thoroughly discussed. Subsequently, the design constraints and physical characteristics of the additively manufactured constructs are reviewed in terms of input parameters such as design features and AM processing parameters. We assess the proposed applications of additively manufactured implants for regeneration of different tissue types and the efforts made towards their clinical translation. Finally, we conclude the review with the emerging directions and perspectives for further development of AM in the medical industry.
Collapse
Affiliation(s)
- Elham Davoodi
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Department of Bioengineering, University of California, Los Angeles, California 90095, United States
- California NanoSystems Institute (CNSI), University of California, Los Angeles, California 90095, United States
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
| | - Hossein Montazerian
- Department of Bioengineering, University of California, Los Angeles, California 90095, United States
- California NanoSystems Institute (CNSI), University of California, Los Angeles, California 90095, United States
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
| | - Anooshe Sadat Mirhakimi
- Department of Mechanical Engineering, Isfahan University of Technology, Isfahan, Isfahan 84156-83111, Iran
| | - Masoud Zhianmanesh
- School of Biomedical Engineering, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Osezua Ibhadode
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Shahriar Imani Shahabad
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Reza Esmaeilizadeh
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Einollah Sarikhani
- Department of Nanoengineering, Jacobs School of Engineering, University of California, San Diego, California 92093, United States
| | - Sahar Toorandaz
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Shima A. Sarabi
- Mechanical and Aerospace Engineering Department, University of California, Los Angeles, California 90095, United States
| | - Rohollah Nasiri
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
| | - Yangzhi Zhu
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
| | - Javad Kadkhodapour
- Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Tehran 16785-163, Iran
- Institute for Materials Testing, Materials Science and Strength of Materials, University of Stuttgart, Stuttgart 70569, Germany
| | - Bingbing Li
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
- Department of Manufacturing Systems Engineering and Management, California State University, Northridge, California 91330, United States
| | - Ali Khademhosseini
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90024, United States
- Corresponding author.
| | - Ehsan Toyserkani
- Multi-Scale Additive Manufacturing (MSAM) Laboratory, Mechanical and Mechatronics Engineering Department, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- Corresponding author.
| |
Collapse
|
6
|
Hosseini-Faradonbeh SA, Katoozian HR. Biomechanical evaluations of the long-term stability of dental implant using finite element modeling method: a systematic review. J Adv Prosthodont 2022; 14:182-202. [PMID: 35855319 PMCID: PMC9259347 DOI: 10.4047/jap.2022.14.3.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 05/07/2022] [Accepted: 05/17/2022] [Indexed: 11/30/2022] Open
Abstract
PURPOSE The aim of this study is to summarize various biomechanical aspects in evaluating the long-term stability of dental implants based on finite element method (FEM). MATERIALS AND METHODS A comprehensive search was performed among published studies over the last 20 years in three databases; PubMed, Scopus, and Google Scholar. The studies are arranged in a comparative table based on their publication date. Also, the variety of modeling is shown in the form of graphs and tables. Various aspects of the studies conducted were discussed here. RESULTS By reviewing the titles and abstracts, 9 main categories were extracted and discussed as follows: implant materials, the focus of the study on bone or implant as well as the interface area, type of loading, element shape, parts of the model, boundary conditions, failure criteria, statistical analysis, and experimental tests performed to validate the results. It was found that most of the studied articles contain a model of the jaw bone (cortical and cancellous bone). The material properties were generally derived from the literature. Approximately 43% of the studies attempted to examine the implant and surrounding bone simultaneously. Almost 42% of the studies performed experimental tests to validate the modeling. CONCLUSION Based on the results of the studies reviewed, there is no "optimal" design guideline, but more reliable design of implant is possible. This review study can be a starting point for more detailed investigations of dental implant longevity.
Collapse
Affiliation(s)
| | - Hamid Reza Katoozian
- Department of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| |
Collapse
|
7
|
Evaluation of the Fatigue Strength of a CAD-CAM Nanoceramic Resin Crown on Titanium and Zirconia-Titanium Abutments. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12031365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A computer-aided design/computer-aided manufacturing (CAD/CAM) resin block material for restoration of single-implant abutments can be milled and cemented on an optimized standard titanium abutment as a cheaper solution or, alternatively, individualization of the crown–abutment connection is required to fulfill the same mechanical requirements. The aim of this study was to evaluate how different structural and geometric configurations of the abutment influence the resistance of a nano ceramic resin crown (NCRC). During the test, 30 implants with an internal conical tapered configuration were considered. Each implant received a standard titanium abutment: in group 1, NCRCs were directly bonded to the titanium abutments; in group 2, NCRCs were cemented on a customized zirconia framework and then cemented on a standardized titanium abutment. Three crowns of each group were submitted to a static load test until failure. The remaining crowns were submitted to a fatigue test protocol with a dynamic load. The static and dynamic test showed earlier failure for group 1. In group 1, complete breaking of NCRCs was observed for all samples, with an almost total titanium abutment exposition. In the static tests, group 2 showed a mode of failure that involved only the crown, which partially debonded from the zirconia abutment. Within the limitations of the present preliminary study, it was possible to conclude that the shape of the abutment mainly influences the fatigue strength compared to the static tensile strength. The results of the performed test show that NCRC bonded to the customized zirconia abutments, and presented a 75% survival rate when compared to the same material bonded directly to a standard titanium abutment.
Collapse
|
8
|
Armentia M, Abasolo M, Coria I, Sainitier N. Effect of the geometry of butt-joint implant-supported restorations on the fatigue life of prosthetic screws. J Prosthet Dent 2022; 127:477.e1-477.e9. [DOI: 10.1016/j.prosdent.2021.12.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 10/19/2022]
|
9
|
Satpathy M, Jose RM, Duan Y, Griggs JA. Effects of abutment screw preload and preload simulation techniques on dental implant lifetime. JADA FOUNDATIONAL SCIENCE 2022; 1:100010. [PMID: 36704641 PMCID: PMC9873498 DOI: 10.1016/j.jfscie.2022.100010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Background This study aimed to investigate how the predicted implant fatigue lifetime is affected by the loss of connector screw preload and the finite element analysis method used to simulate preload. Methods A dental implant assembly (DI1, Biomet-3i external hex; Zimmer Biomet) was scanned using microcomputed tomography and measured using Mimics software (Materialise) and an optical microscope. Digital replicas were constructed using SolidWorks software (Dassault Systèmes). The material properties were assigned in Abaqus (Dassault Systèmes). An external load was applied at 30° off-axial loading. Eight levels of connector screw preload (range, 0-32 Ncm) were simulated for DI1. This assembly and an additional model (DI2) having a longer and narrower screw were compared regarding their fatigue limits (using fe-safe software [Dassault Systèmes]) for 2 preloading methods: (1) adding preload torque or (2) adding bolt axial tension. Results The maximum von Mises stresses of DI1 (on the connector screw threads) with and without preload were 439.90 MPa and 587.90 MPa. The predicted fatigue limit was the same for preloads from 100% through 80% of the manufacturer's recommendation and dropped precipitously between 80% and 70% preload. Adding a preload torque on the screw resulted in a more uniform stress distribution on the screw compared with bolt axial tension, especially for DI2, which had a longer and narrower screw than DI1. Conclusions A substantial loss of preload can be accommodated without compromising the fatigue resistance of this dental implant. Computer models should be constructed using torque instead of a bolt axial tension.
Collapse
Affiliation(s)
- Megha Satpathy
- Biomedical Materials Science, University of Mississippi Medical Center, Jackson, MS
| | - Rose M. Jose
- Biomedical Materials Science, University of Mississippi Medical Center, Jackson, MS
| | - Yuanyuan Duan
- Biomedical Materials Science, University of Mississippi Medical Center, Jackson, MS
| | - Jason A. Griggs
- Biomedical Materials Science, University of Mississippi Medical Center, Jackson, MS
| |
Collapse
|
10
|
García-González M, González-González I, García-García I, Blasón-González S, Lamela-Rey MJ, Fernández-Canteli A, Álvarez-Arenal Á. Effect of abutment finish lines on the mechanical behavior and marginal fit of screw-retained implant crowns: An in vitro study. J Prosthet Dent 2021; 127:318.e1-318.e10. [PMID: 34657727 DOI: 10.1016/j.prosdent.2021.08.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 08/30/2021] [Accepted: 08/30/2021] [Indexed: 11/17/2022]
Abstract
STATEMENT OF PROBLEM The design of the implant-abutment connection has been widely researched, but the impact of different crown-abutment geometries remains unclear. PURPOSE The purpose of this in vitro study was to evaluate the effect of different crown-abutment margin geometries on the mechanical behavior and fit of screw-retained implant-supported single-crown restorations by using mechanical static and fatigue tests and mastication simulation. MATERIAL AND METHODS A total of 45 cobalt-chromium premolar-shaped metal frameworks were fabricated for single-unit implant-supported screw-retained restorations on stock abutments and internal hexagon Ø4.25×11-mm cylindrical implants. They were divided into 3 groups according to margin geometry: S, shoulder; C, chamfer; and F, feather-edge. Three static load until fracture and 24 dynamic load tests were performed by using the International Organization for Standardization 14801:2016 standard (ISO 14801:2016) (number of cycles limit: 5×106 cycles, frequency: 6 Hz). The ProFatigue software program was used to optimize the procedure (S, n=12 specimens; C, n=7 specimens; and F, n=5 specimens). Six additional specimens from each group were subjected to a mastication simulation (limit number of cycles: 1×106 cycles, cyclic loading from Pmin=30 N to Pmax=300 N, frequency: 6 Hz). Results from the fatigue tests were reported descriptively, and the Fisher exact test was used to analyze the difference in failure modes. Data from maximum misfit were evaluated by photogrammetry and statistically analyzed with the Anderson-Darling test and the Kruskal-Wallis and Dunn multiple comparison tests (α=.05). RESULTS The fatigue limit was 456 N for group S, 512 N for group C, and 514 N for group F. The mean ±standard deviation misfit was 2.6 ±0.1 μm for group S, 3.8 ±1.1 μm for group C, and 3.6 ±0.8 μm for group F. Differences in misfit between groups S and C and between groups S and F were statistically significant (P<.05). CONCLUSIONS Crown-abutment connections with chamfer and feather-edge margins showed better mechanical behavior, while shoulder margin exhibited better fit. However, high levels of fit were achieved for all the evaluated geometries.
Collapse
Affiliation(s)
| | - Ignacio González-González
- Associate Professor, Department of Prosthodontics and Occlusion, School of Dentistry, University of Oviedo, Oviedo, Spain
| | - Ismael García-García
- Doctoral student, Department of Construction and Manufacturing Engineering, University of Oviedo, Campus de Viesques, Gijón, Spain
| | - Sergio Blasón-González
- Post-Doctoral Researcher, Department of Component Safety, Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany
| | - María Jesús Lamela-Rey
- Professor, Department of Construction and Manufacturing Engineering, University of Oviedo, Campus de Viesques, Gijón, Spain
| | - Alfonso Fernández-Canteli
- Professor Emeritus, Department of Construction and Manufacturing Engineering, University of Oviedo, Campus de Viesques, Gijón, Spain
| | - Ángel Álvarez-Arenal
- Professor and Head, Department of Prosthodontics and Occlusion, School of Dentistry, University of Oviedo, Oviedo, Spain
| |
Collapse
|
11
|
Armentia M, Abasolo M, Coria I, Albizuri J, Aguirrebeitia J. Fatigue performance of prosthetic screws used in dental implant restorations: Rolled versus cut threads. J Prosthet Dent 2021; 126:406.e1-406.e8. [PMID: 34311946 DOI: 10.1016/j.prosdent.2021.06.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 11/28/2022]
Abstract
STATEMENT OF PROBLEM Cold rolling is widely used for screw thread manufacturing in industry but is less common in implant dentistry, where cutting is the preferred manufacturing method. PURPOSE The purpose of this in vitro study was to compare the surface finish and mechanical performance of a specific model of prosthetic screw used for direct restorations manufactured by thread rolling and cutting. MATERIAL AND METHODS The thread profiles were measured in an optical measuring machine, the residual stresses in an X-ray diffractometer, the surface finish in a scanning electron microscope, and then fatigue and static load tests were carried out in a direct stress test bench according to the International Organization for Standardization (ISO) 14801. Finally, linear regression models and 95% interval confidence bands were calculated and compared through ANCOVA for fatigue tests while the t test was used for statistical comparisons (α=.05). RESULTS The surface finish was smoother, and compressive residual stresses were higher for the roll-threaded screws. Linear regression models showed a fatigue life 9 times higher for roll-threaded screws (P=1) without affecting static behavior, which showed statistically similar static strengths (P=.54). However, the thread profile in the roll-threaded screws was not accurately reproduced, but this should be easily corrected in future prototypes. CONCLUSIONS Rolling was demonstrated to be a better thread-manufacturing process for prosthetic screws, producing improved surface quality and fatigue behavior.
Collapse
Affiliation(s)
- Mikel Armentia
- Doctoral student, Department of Mechanical Engineering, University of the Basque Country, Bilbao, Spain; R&D Engineer, Biotechnology Institute I mas D S.L., Miñano, Spain.
| | - Mikel Abasolo
- Associate Professor, Department of Mechanical Engineering, University of the Basque Country, Bilbao, Spain
| | - Ibai Coria
- Lecturer and Researcher, Department of Mechanical Engineering, University of the Basque Country, Bilbao, Spain
| | - Joseba Albizuri
- Associate Professor, Department of Mechanical Engineering, University of the Basque Country, Bilbao, Spain
| | - Josu Aguirrebeitia
- Associate Professor, Department of Mechanical Engineering, University of the Basque Country, Bilbao, Spain
| |
Collapse
|
12
|
A Parametric Study on a Dental Implant Geometry Influence on Bone Remodelling through a Numerical Algorithm. PROSTHESIS 2021. [DOI: 10.3390/prosthesis3020016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
To ensure the long-term success of a dental implant, it is imperative to understand how chewing loads are transferred through the implant prosthetic components to the surrounding bone tissue. The stress distribution depends on several factors, such as load type, bone–implant interface, shape and materials of the fixture and quality and quantity of the bone. These aspects are of fundamental importance to ensure implant stability and to evaluate the remodelling capacity of the bone tissue to adapt to its biomechanical environment. A bone remodelling algorithm was formulated by the authors and implemented by means of finite element simulations on four different implants with several design characteristics. Internal bone microstructure and density, apposition/resorption of tissue and implant stability were evaluated over a period of 12 months, showing the influence of the geometry on bone tissue evolution over time. Bone remodelling algorithms may be a useful aid for clinicians to prevent possible implant failures and define an adequate implant prosthetic rehabilitation for each patient. In this work, for the first time, external bone remodelling was numerically predicted over time.
Collapse
|