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Barbin T, Borges GA, Jardini AL, Mesquita MF. Hot isostatic pressing as an alternative thermo-mechanical treatment for metallic full-arch implant-supported frameworks obtained by additive and subtractive manufacturing technology: Vertical and horizontal fit, screw removal torque, and stress analysis. J Prosthodont 2024. [PMID: 38513224 DOI: 10.1111/jopr.13842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 02/05/2024] [Accepted: 03/03/2024] [Indexed: 03/23/2024] Open
Abstract
PURPOSE To assess vertical and horizontal fit, screw removal torque, and stress analysis (considered biomechanical aspects) of full-arch implant frameworks manufactured in Ti-6Al-4V through milling, and additive manufacturing Direct Metal Laser Sintering (DMLS) and Electron Beam Melting (EBM), and the effect of the thermo-mechanical treatment Hot Isostatic Pressing (HIP) as a post-treatment after manufacturing. MATERIAL AND METHODS Maxillary full-arch implant frameworks were made by milling, DMLS, and EBM. The biomechanical assessments were screw removal torque, strain-gauge analyses, and vertical and horizontal marginal fits. The vertical fit was assessed by the single-screw test and with all screws tightened. All frameworks were submitted to a standardized HIP cycle (920°C, 1000 bar pressure, 2 h), and the tests were repeated (α = 0.05). RESULTS At the initial time, milled frameworks presented higher screw removal torque values, and DMLS and EBM frameworks presented lower levels of strain. Using the single-screw test, milled and DMLS frameworks presented higher vertical fit values, and with all screws tightened and horizontally, higher fit values were found for milled frameworks, followed by DMLS and EBM. After HIP, milling and EBM frameworks presented higher screw removal torque values; the lowest strain values were found for EBM. Using the single-screw test, milled and DMLS frameworks presented higher vertical fit values, and with all screws tightened and horizontally no differences were found. CONCLUSIONS DMLS and EBM full-arch frameworks presented adequate values of screw removal torque, strain, and marginal fit, although the worst values of marginal fit were found for EBM frameworks. The HIP cycle enhanced the screw removal torque of milled and EBM frameworks and reduced the strain values of milled frameworks. The HIP represents a reliable post-treatment for Ti-6Al-4V dental prostheses produced by milling and EBM technologies.
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Affiliation(s)
- Thaís Barbin
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil
| | - Guilherme Almeida Borges
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil
| | - André Luiz Jardini
- National Institute of Biofabrication, School of Chemical Engineering, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Marcelo Ferraz Mesquita
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil
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Ceddia M, Lamberti L, Trentadue B. FEA Comparison of the Mechanical Behavior of Three Dental Crown Materials: Enamel, Ceramic, and Zirconia. Materials (Basel) 2024; 17:673. [PMID: 38591528 PMCID: PMC10856216 DOI: 10.3390/ma17030673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/24/2024] [Accepted: 01/27/2024] [Indexed: 04/10/2024]
Abstract
The restoration of endodontically treated teeth is one of the main challenges of restorative dentistry. The structure of the tooth is a complex assembly in which the materials that make it up, enamel and dentin, have very different mechanical behaviors. Therefore, finding alternative replacement materials for dental crowns in the area of restorative care isa highly significant challenge, since materials such as ceramic and zirconia have very different stress load resistance values. The aim of this study is to assess which material, either ceramic or zirconia, optimizes the behavior of a restored tooth under various typical clinical conditions and the masticatory load. A finite element analysis (FEA) framework is developed for this purpose. The 3D model of the restored tooth is input into the FEA software (Ansys Workbench R23)and meshed into tetrahedral elements. The presence of masticatory forces is considered: in particular, vertical, 45° inclined, and horizontal resultant forces of 280 N are applied on five contact points of the occlusal surface. The numerical results show that the maximum stress developed in the restored tooth including a ceramic crown and subject to axial load is about 39.381 MPa, which is rather close to the 62.32 MPa stress computed for the natural tooth; stresses of about 18 MPa are localized at the roots of both crown materials. In the case of the zirconia crown, the stresses are much higher than those in the ceramic crown, except for the 45° load direction, while, for the horizontal loads, the stress peak in the zirconia crown is almost three times as large as its counterpart in the ceramic crown (i.e., 163.24 MPa vs. 56.114 MPa, respectively). Therefore, the zirconia crown exhibits higher stresses than enamel and ceramic that could increase in the case of parafunctions, such as bruxism. The clinician's choice between the two materials should be evaluated based on the patient's medical condition.
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Affiliation(s)
| | - Luciano Lamberti
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (M.C.); (B.T.)
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Szabó ÁL, Matusovits D, Slyteen H, Lakatos ÉI, Baráth Z. Biomechanical Effects of Different Load Cases with an Implant-Supported Full Bridge on Four Implants in an Edentulous Mandible: A Three-Dimensional Finite Element Analysis (3D-FEA). Dent J (Basel) 2023; 11:261. [PMID: 37999025 PMCID: PMC10670282 DOI: 10.3390/dj11110261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/29/2023] [Accepted: 11/03/2023] [Indexed: 11/25/2023] Open
Abstract
The long-term success and predictability of implant-supported restorations largely depends on the biomechanical forces (stresses) acting on implants and the surrounding alveolar bone in the mandible. The aim of our study was to investigate the biomechanical behavior of an edentulous mandible with an implant-supported full bridge on four implants under simulated masticatory forces, in the context of different loading schemes, using a three-dimensional finite element analysis (3D-FEA). A patient-specific 3D finite element model was constructed using pre- and post-implantation computer tomography (CT) images of a patient undergoing implant treatment. Simplified masticatory forces set at 300 N were exerted vertically on the denture in four different simulated load cases (LC1-LC4). Two sets of simulations for different implants and denture materials (S1: titanium and titanium; S2: titanium and cobalt-chromium, respectively) were made. Stress outputs were taken as maximum (Pmax) and minimum principal stress (Pmin) and equivalent stress (Peqv) values. The highest peak Pmax values were observed for LC2 (where the modelled masticatory force excluded the cantilevers of the denture extending behind the terminal implants), both regarding the cortical bone (S1 Pmax: 89.57 MPa, S2 Pmax: 102.98 MPa) and trabecular bone (S1 Pmax: 3.03 MPa, S2 Pmax: 2.62 MPa). Overall, LC1-where masticatory forces covered the entire mesio-distal surface of the denture, including the cantilever-was the most advantageous. Peak Pmax values in the cortical bone and the trabecular bone were 14.97-15.87% and 87.96-94.54% higher in the case of S2, respectively. To ensure the long-term maintenance and longevity of treatment for implant-supported restorations in the mandible, efforts to establish the stresses of the surrounding bone in the physiological range, with the most even stress distribution possible, have paramount importance.
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Affiliation(s)
- Árpád László Szabó
- Department of Prosthodontics, Faculty of Dentistry, University of Szeged, Tisza Lajos krt. 64-66., 6720 Szeged, Hungary; (Á.L.S.); (D.M.)
| | - Danica Matusovits
- Department of Prosthodontics, Faculty of Dentistry, University of Szeged, Tisza Lajos krt. 64-66., 6720 Szeged, Hungary; (Á.L.S.); (D.M.)
| | - Haydar Slyteen
- Department of Structural Mechanics, Faculty of Civil Engineering, University of Technology and Economics, Budapest, Műegyetem rkp. 3., 1111 Budapest, Hungary; (H.S.); (É.I.L.)
| | - Éva Ilona Lakatos
- Department of Structural Mechanics, Faculty of Civil Engineering, University of Technology and Economics, Budapest, Műegyetem rkp. 3., 1111 Budapest, Hungary; (H.S.); (É.I.L.)
| | - Zoltán Baráth
- Department of Prosthodontics, Faculty of Dentistry, University of Szeged, Tisza Lajos krt. 64-66., 6720 Szeged, Hungary; (Á.L.S.); (D.M.)
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Tonin BSH, Peixoto RF, Fu J, De Mattos MDGC, Macedo AP. Influence of the frameworks of implant-supported prostheses and implant connections on stress distribution. Dent Med Probl 2023; 60:551-557. [PMID: 38100082 DOI: 10.17219/dmp/153060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/31/2022] [Accepted: 08/29/2022] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND The maintenance of marginal bone integrity around dental implants continues to be a clinical challenge. It is still unclear whether loading multiple implant-supported prostheses that have different implant connections influences bone resorption. OBJECTIVES The aim of this in vitro study was to compare stress distribution around residual edentulous ridges supported by external hexagon (EH) and Morse taper (MT) implants with screw-retained frameworks obtained with the use of different methods. MATERIAL AND METHODS Three-element implant-supported prostheses with distal cantilevers were manufactured according to different techniques of obtaining the framework: LAS - framework sectioned and welded with a laser; TIG - framework sectioned and welded with tungsten inert gas (TIG); and CCS - framework obtained using a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Occlusal and punctual loading (150 N) was applied to the cantilevers. In the photoelastic stress analysis, the fringe orders (n) were quanitified using the Tardy method, which calculates the maximum shear stress value (τ) at each selected point. RESULTS High stress around the implants and tightening were observed in the TIG group, mainly in the crestal bone region for the EH and MT implant connections. The LAS and CCS frameworks exhibited lower stress for the MT connection under occlusal and punctual loading. CONCLUSIONS The comparative analysis of the models showed that the MT connection type associated with the laser-welded or CAD/CAM frameworks resulted in lower stress values in the crestal bone area, suggesting the preservation of bone tissue in this region.
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Affiliation(s)
- Bruna Santos Honório Tonin
- Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Raniel Fernandes Peixoto
- Department of Restorative Dentistry, Faculty of Pharmacy, Dentistry and Nursing, Federal University of Ceará, Fortaleza, Brazil
| | - Jing Fu
- Department of Prosthodontics, the Affiliated Hospital of Qingdao University, China
| | | | - Ana Paula Macedo
- Department of Dental Materials and Prosthesis, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
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Baaj R, Khalili M, Luke A, Weiner S. Strains in the implant collars supporting a cantilevered cross-arch bar prosthesis. An in vitro study. J Prosthodont 2023; 32:735-742. [PMID: 36648444 DOI: 10.1111/jopr.13649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 01/18/2023] Open
Abstract
PURPOSE To examine the strains in the collar area of implants supporting a cantilevered cross-arch bar prosthesis during vertical load application. MATERIALS AND METHODS A milled cross-arch metal framework supported by four implants in a trapezoidal design was supported in polymethylmethacrylate. T-strain gage rosettes were attached to the crestal areas of the implants with two grids, one recording circumference strain of the crestal area of the implant and the second recording vertical strain, torquing strains of the implant. The framework was subject to vertical loading from an MTS 810 mechanical system. Loading sites were directly on anterior and posterior implants, and on a cantilever at 7.5, 15, 22.5, and 30 mm (0.5, 1.0, 1.5, and 2.0 of the anterior-posterior spread) distal from the posterior implant on the right side. The anterior-posterior (A-P) spread from anterior to posterior implants was 15 mm. Sites were loaded individually with 50 and 100 N. The data from the rosettes were transferred to a desktop computer and processed using StrainSmart 5000 software. RESULTS Means and standard deviations were calculated for the 10 trials at each of the loading sites. Two-way ANOVAs were done separately for each dependent variable, the vertical grid, and the circumferential grid. The independent variables were the load magnitude and the load site. Tukey's test was used to compare groups post hoc. When directly loading the implants, loading the anterior implant resulted initially in compression followed by increasing tensile strain with 100 N loads. Loading the implant adjacent to cantilever (the posterior implant) resulted in greater strain at the collar than that observed with anterior implant with minimal bending strains. When loading the cantilever, anterior implant showed increasing bending strain at greater cantilever length, whereas the circumferential strains were greater for the supporting implant adjacent to the cantilever, particularly at 100 N loads, p ≤ 0.001. CONCLUSIONS Limiting cantilever lengths to A-P spread ratios of 0.5 are preferred. Ratios greater than 1.0 should be avoided as flexing of the collar may occur. The dimensions of the implant, particularly wall thickness, adjacent to the cantilever should be carefully considered when planning the cantilevered implant-supported prosthesis.
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Affiliation(s)
- Rakan Baaj
- Department of Prosthodontics, Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - Maryam Khalili
- Department of Restorative Dentistry, Temple University Maurice H. Kornberg School of Dentistry, Philadelphia, Pennsylvania, USA
| | - Allyn Luke
- Department of Restorative Dentistry, Rutgers University School of Dental Medicine, Newark, New Jersey, USA
| | - Saul Weiner
- Department of Restorative Dentistry, Rutgers University School of Dental Medicine, Newark, New Jersey, USA
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey, USA
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Yildiz S, Tekin S, Kizilkaya AR, Akgün SE, Deger Y. Comparative Stress Analysis of Custom-Made PEEK Dental Post-Cores versus Conventional Post-Cores in Incisor Restorations: A Finite Element Study. Med Sci Monit 2023; 29:e940887. [PMID: 37587670 PMCID: PMC10443227 DOI: 10.12659/msm.940887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 07/07/2023] [Indexed: 08/18/2023] Open
Abstract
BACKGROUND We conducted a finite element analysis to evaluate stress levels in incisor teeth restored with custom polyetheretherketone (PEEK) dental post-cores compared to conventional post-cores. MATERIAL AND METHODS Using micro-computed tomography (μCT) imaging data, a 3D model of a maxillary incisor was created. For each material type, 3D mesh models were developed via specialized software. Two post diameters, 2.5 mm and 3.5 mm, were considered. Five different post materials were examined: Unfilled polyetheretherketone (Group UP); Glass fiber-reinforced polyetheretherketone (Group GP); Carbon fiber-reinforced polyetheretherketone (Group CP); Metal (Group M); and Zirconia ceramic (Group Z). Each model underwent finite element analysis, after which the von Mises equivalent stress values were determined. RESULTS For models involving both wide and narrow diameter posts across the crown, crown cement, post cement, and dentin, PEEK posts (Group UP, GP, and CP) exhibited higher von Mises stress values than Groups Z and M. However, the reverse trend was noticed in the post model itself. In the post cement model, stress values appeared similar only for the narrow-diameter post groups. Notably, results for Groups Z and M were largely consistent with each other. CONCLUSIONS PEEK posts, which have a lower modulus of elasticity, demonstrated different stress values when contrasted with zirconia and metal posts. As the post diameter expanded, the residual dentin decreased, influencing the stress values among various materials. Further in vitro and clinical examinations are essential to comprehensively understand PEEK posts.
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Affiliation(s)
- Semsettin Yildiz
- Department of Pediatric Dentistry, Faculty of Dentistry, Firat University, Elazig, Turkey
| | - Samet Tekin
- Department of Prosthodontics, Faculty of Dentistry, Firat University, Elazig, Turkey
| | | | - Semih Ercan Akgün
- Pediatric Dentistry Clinic, Bafra Oral and Dental Health Center, Samsun, Turkey
| | - Yalcin Deger
- Department of Prosthodontics, Faculty of Dentistry, Dicle University, Diyarbakir, Turkey
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Malgaj T, Papšík R, Abram A, Kocjan A, Jevnikar P. Bonding Performance of Surface-Treated Zirconia Cantilevered Resin-Bonded Fixed Dental Prostheses: In Vitro Evaluation and Finite Element Analysis. Materials (Basel) 2023; 16:2646. [PMID: 37048940 PMCID: PMC10095828 DOI: 10.3390/ma16072646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/22/2023] [Accepted: 03/24/2023] [Indexed: 06/19/2023]
Abstract
Debonding of zirconia cantilevered resin-bonded fixed dental prostheses (RBFDPs) remains the main treatment complication, therefore, the present in vitro study aimed to evaluate the effect of different surface pretreatments on the bonding of zirconia RBFDPs. Eighty milled zirconia maxillary central incisors, with complementary zirconia cantilevered RBFDPs, were randomly subjected to four different surface pretreatments (n = 20): as-machined (AM); airborne-particle abraded (APA); coated with nanostructured alumina coating (NAC); incisor air-abraded and RBFDP coated (NAC_APA). After bonding, half of each group (n = 10) was stored in deionized water (150 days/37 °C), thermocycled (37,500 cycles, 5-55 °C), and cyclically loaded (50 N/1.2 × 106). Load-bearing capacity (LBC) was determined using a quasi-static test. Additionally, finite element analysis (FEA) and fractography were performed. t-test and one-way ANOVA were used for statistical-analysis. Before aging, the NAC group provided superior LBC to other groups (p < 0.05). After aging, the AM specimens debonded spontaneously, while other groups exhibited comparable LBC (p ˃ 0.05). The FEA results correlated with the in vitro experiment and fractography, showing highly stressed areas in the bonding interface, cement layer, and in RBFDP's retainer wing and connector. The NAC RBFDPs exhibited comparable long-term bonding performance to APA and should be regarded as a zirconia pretreatment alternative to APA.
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Affiliation(s)
- Tine Malgaj
- Department of Prosthodontics, Faculty of Medicine, University of Ljubljana, Hrvatski trg 6, 1000 Ljubljana, Slovenia
| | - Roman Papšík
- Department of Material Science, Montanuniversität Leoben, A-8700 Leoben, Austria
| | - Anže Abram
- Department for Nanostructured Materials, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
| | - Andraž Kocjan
- Department for Nanostructured Materials, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
| | - Peter Jevnikar
- Department of Prosthodontics, Faculty of Medicine, University of Ljubljana, Hrvatski trg 6, 1000 Ljubljana, Slovenia
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Spitznagel FA, Hoppe JS, Bonfante EA, Campos TMB, Langner R, Gierthmuehlen PC. Failure Load and Fatigue Behavior of Monolithic and Bi-Layer Zirconia Fixed Dental Prostheses Bonded to One-Piece Zirconia Implants. Materials (Basel) 2022; 15:8465. [PMID: 36499960 PMCID: PMC9740162 DOI: 10.3390/ma15238465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/19/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
No evidence-based prosthetic treatment concept for 3-unit fixed-dental-prostheses (FDPs) on ceramic implants is currently available. Therefore, the aim of this in vitro study was to investigate the failure load and fatigue behavior of monolithic and bi-layer zirconia FDPs supported by one-piece ceramic implants. Eighty 3-unit FDPs supported by 160 zirconia-implants (ceramic.implant; vitaclinical) were divided into 4 groups (n = 20 each): Group Z-HT: 3Y-TZP monolithic-zirconia (Vita-YZ-HT); Group Z-ST: 4Y-TZP monolithic-zirconia (Vita-YZ-ST); Group FL: 3Y-TZP zirconia (Vita-YZ-HT) with facial-veneer (Vita-VM9); Group RL (Rapid-layer): PICN “table-top” (Vita-Enamic), 3Y-TZP-framework (Vita-YZ-HT). Half of the test samples (n = 10/group) were fatigued in a mouth-motion chewing-simulator (F = 98 N, 1.2 million-cycles) with simultaneous thermocycling (5−55 °C). All specimens (fatigued and non-fatigued) were afterwards exposed to single-load-to-failure-testing (Z010, Zwick). Statistical analysis was performed using ANOVA, Tukey’s post-hoc tests and two-sample t-tests (p < 0.05, Bonferroni-corrected where appropriate). All specimens withstood fatigue application. While the effect of fatigue was not significant in any group (p = 0.714), the choice of material had a significant effect (p < 0.001). Material FL recorded the highest failure loads, followed by Z-ST, Z-HT and RL, both with and without fatigue application. Taken together, all tested FDP material combinations survived chewing forces that exceeded physiological levels. Bi-Layer FL and monolithic Z-ST showed the highest resilience and might serve as reliable prosthetic reconstruction concepts for 3-unit FDPs on ceramic implants.
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Affiliation(s)
- Frank A. Spitznagel
- Department of Prosthodontics, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, Moorenstraße 5, 40225 Düsseldorf, Germany
| | - Johanna S. Hoppe
- Department of Prosthodontics, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, Moorenstraße 5, 40225 Düsseldorf, Germany
| | - Estevam A. Bonfante
- Department of Prosthodontics and Periodontology; Bauru School of Dentistry, University of Sao Paulo, Bauru 17012-230, SP, Brazil
| | - Tiago M. B. Campos
- Department of Prosthodontics and Periodontology; Bauru School of Dentistry, University of Sao Paulo, Bauru 17012-230, SP, Brazil
| | - Robert Langner
- Institute of Systems Neuroscience, Medical Faculty, Heinrich-Heine-University, 40225 Düsseldorf, Germany
- Institute of Neuroscience and Medicine, Brain and Behavior (INM-7), Research Center Jülich, 52425 Jülich, Germany
| | - Petra C. Gierthmuehlen
- Department of Prosthodontics, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University, Moorenstraße 5, 40225 Düsseldorf, Germany
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Grachev DI, Ruzuddinov NS, Arutyunov AS, Akhmedov GD, Dubova LV, Kharakh YN, Panin SV, Arutyunov SD. Algorithm for Designing a Removable Complete Denture (RCD) Based on the FEM Analysis of Its Service Life. Materials (Basel) 2022; 15:7246. [PMID: 36295314 PMCID: PMC9610509 DOI: 10.3390/ma15207246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/10/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
(1) Background: The paper addresses the computer simulation and prediction of the service life of the base of removable complete dentures (RCDs) under typical loads caused by biting and chewing food. For this purpose, the finite element method (FEM) was used. It is assumed that various blocks of teeth, such as incisors, canines, premolars and molars, are subjected to cyclic impacts during a human life. (2) Methods: Both symmetric and asymmetric mastication (two- and one-sided loads, respectively) cases were considered. The load level was assumed to be 100 N, which corresponds to the average muscular compression force of typical human jaws. (3) Results: The FEM analysis of the stress-strain state evolution for RCDs under cyclic loads was carried out. Maps of equivalent lines were drawn for the denture base in terms of its durability. A multi-axial criterion was implemented to determine the number of cycles prior to failure by the mechanism of a normal opening mode crack. The FEM-based assessment of the service life of RCDs enabled us to establish the critical stress concentration areas, thereby allowing for further planning for the correction of an occlusal scheme or teeth inclinations. As a result, the service life of RCDs under cyclic loading can be improved. (4) Conclusions: An algorithm for designing RCDs in the case of edentulism based on the FEM simulation using commercial software as part of the procedure is proposed.
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Affiliation(s)
- Dmitry I. Grachev
- Digital Dentistry Department, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | | | - Anatoliy S. Arutyunov
- Propaedeutics of Prosthetics Technologies in Dentistry Department, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Gadzhi D. Akhmedov
- Propaedeutics in Surgical Dentistry, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Lubov V. Dubova
- Orthopedic Dentistry Department, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Yaser N. Kharakh
- Digital Dentistry Department, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
| | - Sergey V. Panin
- Laboratory of Mechanics of Polymer Composite Materials, Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences, 634055 Tomsk, Russia
| | - Sergey D. Arutyunov
- Digital Dentistry Department, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, 127473 Moscow, Russia
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Asokan S, Pollachi Ramakrishnan G, Ranganatham KV, Viswanath S, Sivasamy S. Stress amongst paediatric dental postgraduate students in India: A mixed-method approach. Eur J Dent Educ 2022; 26:629-638. [PMID: 34904332 DOI: 10.1111/eje.12740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 05/09/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
INTRODUCTION Dental profession is one of the most stressful healthcare occupations. Paediatric dental postgraduates face multifaceted challenges in their everyday practice. This study aimed to determine the sources of stress amongst paediatric dental postgraduate students in India using a mixed-method approach. MATERIALS AND METHODS A sequential mixed-methods approach was employed. In the quantitative phase, a cross-sectional web-based questionnaire survey was conducted amongst paediatric dental postgraduates in India using the "Google Forms application" link. Based on the Dental Environment Stress (DES) questionnaire, the stress PACT questionnaire which includes 35 items was framed and validated. This validated questionnaire was used in the survey. In the qualitative phase, one-on-one, semi-structured telephone interviews were conducted amongst 12 postgraduates. RESULTS A total of 422 participants took part in the quantitative survey. Academic and specialty-related domains were found to be the significant causes of stress amongst the five domains (p < .001). The top three stressful factors were as follows: getting an ideal case for clinical exams (68.2%), financial resources for conferences, dissertation, short studies and publications (53.2%) and fear of unemployment after graduation (52.3%). Based on qualitative interviews, four themes were derived, namely choice of paediatric dentistry, postgraduate life experience, stress management and expected changes in postgraduate life. CONCLUSION Psychological well-being of the student is an important factor that influences the overall performance of students. Identifying the stress factors and using appropriate coping strategies can help postgraduates achieve personal, academic and professional success.
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Affiliation(s)
- Sharath Asokan
- Pediatric and Preventive Dentistry, KSR Institute of Dental Science and Research, Tiruchengode, India
| | | | | | - Sudhandra Viswanath
- Pediatric and Preventive Dentistry, KSR Institute of Dental Science and Research, Tiruchengode, India
| | - Shyam Sivasamy
- Public Health Dentistry, Meenakshi Academy of Higher Education and Research, Chennai, India
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11
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Gürbüz A, Güçlü ZB, Deste Gökay G, Durkan R. Biomechanical comparison of different prosthetic materials and posterior implant angles in all-on-4 treatment concept by three-dimensional finite element analysis. BIOMED ENG-BIOMED TE 2022; 67:307-315. [PMID: 35587648 DOI: 10.1515/bmt-2022-0109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/21/2022] [Indexed: 11/15/2022]
Abstract
The study aimed to evaluate the biomechanical behaviors of different prosthetic materials and posterior implant angles in All-on-4 implant-supported fixed maxillary prostheses with three-dimensional (3D) finite element analysis. The model of complete edentulous maxilla was created using the Rhinoceros and VRMesh Studio programs. Anterior vertical and 17°- and 30°-angled posterior implants were positioned with All-on-4 design. Straigth and angled multi-unit abutments scanned using a 3D scanner. Two different prosthetic superstructures (monolithic zirconia framework and lithium disilicate veneer (ZL) and monolithic zirconia-reinforced lithium silicate (ZLS)) were modeled. Four models designed according to the prosthetic structure and posterior implant angles. Posterior vertical bilateral loading and frontal oblique loading was performed. The principal stresses (bone tissues-Pmax and Pmin) and von Mises equivalent stresses (implant and prosthetic structures) were analyzed. In all models, the highest Pmax stress values were calculated under posterior bilateral loading in cortical bone. The highest von Mises stress levels occured in the posterior implants under posterior bilateral load (260.33 and 219.50 MPa) in the ZL-17 and ZL-30 models, respectively. Under both loads, higher stress levels in prosthetic structures were shown in the ZLS models compared with ZL models. There was no difference between posterior implant angles on stress distribution occurred in implant material and alveolar bone tissue. ZLS and ZL prosthetic structures can be reliably used in maxillary All-on-4 rehabilitation.
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Affiliation(s)
- Ayhan Gürbüz
- Department of Prosthodontics, Faculty of Dentistry, Ankara University, Ankara, Turkey
| | - Zekiye Begüm Güçlü
- Department of Prosthodontics, Faculty of Dentistry, Ankara University, Ankara, Turkey
| | - Gonca Deste Gökay
- Department of Prosthodontics, Faculty of Dentistry, Bursa Uludağ University, Bursa, Turkey
| | - Rukiye Durkan
- Department of Prosthodontics, Faculty of Dentistry, Istanbul Okan University, Istanbul, Turkey
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Kim HK, Yoo KW, Kim SJ, Jung CH. Phase Transformations and Subsurface Changes in Three Dental Zirconia Grades after Sandblasting with Various Al 2O 3 Particle Sizes. Materials (Basel) 2021; 14:5321. [PMID: 34576556 DOI: 10.3390/ma14185321] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/08/2021] [Accepted: 09/14/2021] [Indexed: 01/10/2023]
Abstract
Although sandblasting is mainly used to improve bonding between dental zirconia and resin cement, the details on the in-depth damages are limited. The aim of this study was to evaluate phase transformations and subsurface changes after sandblasting in three different dental zirconia (3, 4, and 5 mol% yttria-stabilized zirconia; 3Y-TZP, 4Y-PSZ, and 5Y-PSZ). Zirconia specimens (14.0 × 14.0 × 1.0 mm3) were sandblasted using different alumina particle sizes (25, 50, 90, 110, and 125 µm) under 0.2 MPa for 10 s/cm2. Phase transformations and residual stresses were investigated using X-ray diffraction and the Williamson-Hall method. Subsurface damages were evaluated with cross-sections by a focused ion beam. Stress field during sandblasting was simulated by the finite element method. The subsurface changes after sandblasting were the emergence of a rhombohedral phase, micro/macro cracks, and compressive/tensile stresses depending on the interactions between blasting particles and zirconia substrates. 3Y-TZP blasted with 110-µm particles induced the deepest transformed layer with the largest compressive stress. The cracks propagated parallel to the surface with larger particles, being located up to 4.5 µm under the surface in 4Y- or 5Y-PSZ subgroups. The recommended sandblasting particles were 110 µm for 3Y-TZP and 50 µm for 4Y-PSZ or 5Y-PSZ for compressive stress-induced phase transformations without significant subsurface damages.
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13
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Gribov D, Antonik M, Butkov D, Stepanov A, Antonik P, Kharakh Y, Pivovarov A, Arutyunov S. Personalized Biomechanical Analysis of the Mandible Teeth Behavior in the Treatment of Masticatory Muscles Parafunction. J Funct Biomater 2021; 12:23. [PMID: 33918647 DOI: 10.3390/jfb12020023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/04/2021] [Accepted: 04/06/2021] [Indexed: 01/25/2023] Open
Abstract
A 3D finite element model of the mandible dentition was developed, including 14 teeth, a periodontal ligament (PDL), and a splint made of polymethylmethacrylate (PMMA). The study considered three design options: 1—the case of splint absence; 2—the case of the splint presence installed after manufacture; and 3—the case of splint presence installed after correction (grinding) performed to ensure a uniform distribution of occlusal force between the teeth. For cases of absence and presence of splint, three measurements of the functional load were performed using the T-Scan III software and hardware complex (TekScan, Boston, MA, USA). It was found that the presence of a splint led to a decrease in the total value of the occlusive load and to a uniform distribution between all the mandible teeth. The occlusal force was considered as a static vertical force evenly distributed between the nodes belonging to the occlusive surface of the corresponding tooth for the first design option and the occlusal surface of the splint for the second and third ones, respectively. As a result of the study, it was concluded that the splint usage was effective in order to change the distribution of the functional load during the treatment of proved masticatory muscles’ parafunction; the safety of using a splint for teeth and surrounding tissues under the influence of the considered functional load was shown; the potential applicability of PMMA as a structural material of a splint that had been used for the treatment of masticatory muscles’ parafunction was established.
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Kim HK, Ahn B. Effect of Al 2O 3 Sandblasting Particle Size on the Surface Topography and Residual Compressive Stresses of Three Different Dental Zirconia Grades. Materials (Basel) 2021; 14:610. [PMID: 33525702 DOI: 10.3390/ma14030610] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 01/25/2023]
Abstract
This study investigated the effect of sandblasting particle size on the surface topography and compressive stresses of conventional zirconia (3 mol% yttria-stabilized tetragonal zirconia polycrystal; 3Y-TZP) and two highly translucent zirconia (4 or 5 mol% partially stabilized zirconia; 4Y-PSZ or 5Y-PSZ). Plate-shaped zirconia specimens (14.0 × 14.0 × 1.0 mm3, n = 60 for each grade) were sandblasted using different Al2O3 sizes (25, 50, 90, 110, and 125 μm) under 0.2 MPa for 10 s/cm2 at a 10 mm distance and a 90° angle. The surface topography was characterized using a 3-D confocal laser microscopy and inspected with a scanning electron microscope. To assess residual stresses, the tetragonal peak shift at 147 cm−1 was traced using micro-Raman spectroscopy. Al2O3 sandblasting altered surface topographies (p < 0.05), although highly translucent zirconia showed more pronounced changes compared to conventional zirconia. 5Y-PSZ abraded with 110 μm sand showed the highest Sa value (0.76 ± 0.12 μm). Larger particle induced more compressive stresses for 3Y-TZP (p < 0.05), while only 25 μm sand induced residual stresses for 5Y-PSZ. Al2O3 sandblasting with 110 μm sand for 3Y-TZP, 90 μm sand for 4Y-PSZ, and 25 μm sand for 5Y-PSZ were considered as the recommended blasting conditions.
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15
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Markham MD, Tsujimoto A, Barkmeier WW, Jurado CA, Fischer NG, Watanabe H, Baruth AG, Latta MA, Garcia-Godoy F. Influence of 38% silver diamine fluoride application on bond stability to enamel and dentin using universal adhesives in self-etch mode. Eur J Oral Sci 2020; 128:354-360. [PMID: 32395905 DOI: 10.1111/eos.12701] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2020] [Indexed: 11/29/2022]
Abstract
In order to evaluate the influence of 38% silver diamine fluoride (SDF) application on enamel and dentin bond stability of universal adhesives in self-etch mode, a 38% SDF and three universal adhesives were used in this study. Initial shear bond strength (ISBS), fatigue bond strength (FBS), and shear bond strength of survivors (SBSS) to enamel and dentin of universal adhesives in self-etch mode, with and without SDF application, were determined. SDF was applied to the polished enamel or dentin surface for 1 min, water-rinsed and air-dried for comparison with controls. The universal adhesives were applied to the prepared samples and composite resin was bonded using a mold-enclosed method. Enamel bond stability of universal adhesives with SDF (ISBS: 14.7-20.4 MPa; FBS: 5.5-7.4 MPa and SBSS: 14.4-21.5 MPa) was significantly weaker than those without SDF (ISBS: 28.0-29.2 MPa; FBS: 12.1-15.6 MPa and SBSS: 28.4-34.4 MPa). Dentin bond stability with SDF (ISBS: 14.8-20.9 MPa; FBS: 7.1-8.2 MPa and SBSS: 17.3-21.8 MPa) was also significantly weaker than without SDF (ISBS: 19.3-36.1 MPa; FBS: 11.0-13.7 MPa and SBSS: 22.2-34.6 MPa). The results suggest that SDF application on enamel and dentin reduces the bond stability of universal adhesives in self-etch mode.
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Affiliation(s)
- Mark D Markham
- Department of General Dentistry, Creighton University School of Dentistry, Omaha, NE, USA
| | - Akimasa Tsujimoto
- Department of General Dentistry, Creighton University School of Dentistry, Omaha, NE, USA.,Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan
| | - Wayne W Barkmeier
- Department of General Dentistry, Creighton University School of Dentistry, Omaha, NE, USA
| | - Carlos A Jurado
- Clinical Digital Dentistry, A.T. Still University Arizona School of Dentistry & Oral Health, Mesa, AZ, USA
| | - Nicholas G Fischer
- Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota School of Dentistry, Minneapolis, MN, USA
| | - Hidehiko Watanabe
- Department of Restorative Dentistry, Oregon Health and Science University School of Dentistry, Portland, OR, USA
| | - Andrew G Baruth
- Department of Physics, Creighton University College of Arts and Sciences, Omaha, NE, USA
| | - Mark A Latta
- Department of General Dentistry, Creighton University School of Dentistry, Omaha, NE, USA
| | - Franklin Garcia-Godoy
- Department of Bioscience Research, University of Tennessee Health Science Center College of Dentistry, Memphis, TN, USA
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林 春, 卢 松, 朱 浚, 胡 洪, 岳 兆, 唐 志. [Influence of thread shapes of custommade root-analogue implants on stress distribution of peri-implant bone: A three-dimensional finite element analysis]. Beijing Da Xue Xue Bao Yi Xue Ban 2019; 51:1130-1137. [PMID: 31848517 PMCID: PMC7433572 DOI: 10.19723/j.issn.1671-167x.2019.06.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Indexed: 06/10/2023]
Abstract
OBJECTIVE To explore the effects from the thread shapes of custom-made root-analogue implant (RAI) on distributions of von Mises stress around the peri-implant bone. METHODS Five one-stage RAI three-dimensional finite element (FE) models with different thread shapes (V-shaped design, square design, buttress design, reverse buttress design and none thread design) and congruent bone were created through reverse engineering technology. The data of the five models were imported into the FE analysis software to calculate. A force of 100 N was applied parallelly and of 45° to the implant axis respectively. Analysis was performed to evaluate the von Mises stress distributions at the peri-implant regions with the help of the Ansys 16 software. RESULTS The von Mises stresses distributed mostly at the implant cervical regions and the tip ends of the threads on the cortical bone under oblique loading, while on the cancellous bone, the stresses concentrated mostly on the implant lateral cervical regions, the tip ends of the threads and the apical regions. When under vertical loading, the von Mises stresses distributed mostly at the implant cervical regions on the cortical bone while at the tip ends of the threads and the lateral apical regions on the cancellous bone. The von Mises stresses were better distributed on the thread groups under both kinds of loadings compared with no thread design. But there was no obvious difference among the different thread groups. The concentrations of the von Mises stresses on the cancellous bone in the thread groups were mostly at the tip ends of the threads while less in the apical area. The von Mises stresses were better distributed on the cancellous bone on the other three thread designs than on square design. CONCLUSION Thread designs are advocated for the reason that adding thread designs to the RAI standard design will have a positive effect on stress distributions at the peri-implant regions and it will reduce the concentrations of von Mises stresses on the cortical bone. From the standpoint of the stress distribution, V-shaped design, buttress design and reverse buttress design are more suitable for RAI than square design. There is no difference of the distributions of the von Mises stresses in the RAI between different thread designs.
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Affiliation(s)
- 春平 林
- 北京大学口腔医学院·口腔医院,牙周科 口腔数字化医疗技术和材料国家工程实验室 口腔数字医学北京市重点实验室, 北京 100081Department of Periodontitis, Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China
| | - 松鹤 卢
- 北京大学口腔医学院·口腔医院第二门诊部, 北京 100101Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing 100101, China
| | - 浚鑫 朱
- 北京大学口腔医学院·口腔医院第二门诊部, 北京 100101Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing 100101, China
| | - 洪成 胡
- 北京大学口腔医学院·口腔医院第二门诊部, 北京 100101Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing 100101, China
| | - 兆国 岳
- 北京大学口腔医学院·口腔医院第二门诊部, 北京 100101Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing 100101, China
| | - 志辉 唐
- 北京大学口腔医学院·口腔医院第二门诊部, 北京 100101Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing 100101, China
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17
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Yamauchi K, Tsujimoto A, Jurado CA, Shimatani Y, Nagura Y, Takamizawa T, Barkmeier WW, Latta MA, Miyazaki M. Etch-and-rinse vs self-etch mode for dentin bonding effectiveness of universal adhesives. J Oral Sci 2019; 61:549-553. [PMID: 31631096 DOI: 10.2334/josnusd.18-0433] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
In this study, dentin bond fatigue resistance and interfacial science characteristics of universal adhesives through etch-and-rinse and self-etch modes were investigated. Resin composite was bonded to human dentin with four universal adhesives, namely, Adhese Universal, All-Bond Universal, G-Premio Bond, and Scotchbond Universal Adhesive. The initial bond strengths, bond fatigue strengths, and interfacial science characteristics of the universal adhesives with dentin through etch-and-rinse and self-etch modes were determined. Bond fatigue resistance (initial bond strength and bond fatigue strength) of universal adhesives in etch-and-rinse mode showed no significant difference in contrast to that in self-etch mode and was material-dependent regardless of the etching mode. Although phosphoric acid conditioning of dentin did not have a strong impact on the bond fatigue resistance, surface free energy and parameters of dentin were significantly decreased by etching and by application of universal adhesives regardless of etching mode. Changes in γS and γSh for when universal adhesive was applied to etched and ground dentin were significantly different depending on the adhesive. The results suggest that bonding performance of universal adhesives was effective in both etching modes; however, bonding mechanisms may be different for each.
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Affiliation(s)
- Kabun Yamauchi
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Akimasa Tsujimoto
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Carlos A Jurado
- Department of Restorative Dentistry, Oregon Health and Science University School of Dentistry.,Department of Digital Dentistry, A.T. Still University Arizona School of Dentistry
| | - Yusuke Shimatani
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Yuko Nagura
- Department of Operative Dentistry, Nihon University School of Dentistry
| | | | - Wayne W Barkmeier
- Department of General Dentistry, Creighton University School of Dentistry
| | - Mark A Latta
- Department of General Dentistry, Creighton University School of Dentistry
| | - Masashi Miyazaki
- Department of Operative Dentistry, Nihon University School of Dentistry
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Pereira R, Giorgi MCC, Lins RBE, Theobaldo JD, Lima DANL, Marchi GM, Aguiar FHB. Physical and photoelastic properties of bulk-fill and conventional composites. Clin Cosmet Investig Dent 2018; 10:287-296. [PMID: 30588124 PMCID: PMC6296192 DOI: 10.2147/ccide.s184660] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose This study evaluated the influence of thickness increment on degree of conversion (DC), Knoop microhardness (KHN), and polymerization-shrinkage stress (PSS) by photoelasticity of three dental composites. Methods For DC and KHN, 45 samples were prepared and divided into nine groups (n=5), according to composite (microhybrid [Filtek Z250 - Z250], bulk-fill flowable [SureFil SDR Flow - SDR], and nanohybrid composite [N’Durance - NDU]) and increment thickness (1, 1.5, and 3 mm). PSS was measured by photoelastic analysis. Composites were placed into a photo-elastic model cavity and light-cured. DC and KHN data were subjected to two-way ANOVA and Bonferroni post hoc test. PSS results were qualitatively evaluated through Kruskal–Wallis test. Results SDR showed the highest DC values. At top and bottom surfaces, the highest KHN was obtained by Z250. Z250 showed higher PSS than SDR in 1.5 mm increments. NDU showed higher PSS than SDR in 3 mm increments. Conclusion The bulk-fill composite demonstrated better DC and similar KHN and PSS in deeper layers compared to conventional composites. Bulk-fill composites may perform as well as conventional nanohybrid and microhybrid composites.
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Affiliation(s)
- Renata Pereira
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
| | - Maria Cecília Caldas Giorgi
- Department of Operative Dentistry, School of Health Sciences, State University of Amazonas, Manaus, AM 69065-001, Brazil
| | - Rodrigo Barros Esteves Lins
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
| | - Jéssica Dias Theobaldo
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
| | - Débora Alves Nunes Leite Lima
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
| | - Giselle Maria Marchi
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
| | - Flávio Henrique Baggio Aguiar
- Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, SP 13.414-903, Brazil,
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Maminskas J, Puisys A, Kuoppala R, Raustia A, Juodzbalys G. The Prosthetic Influence and Biomechanics on Peri-Implant Strain: a Systematic Literature Review of Finite Element Studies. J Oral Maxillofac Res 2016; 7:e4. [PMID: 27833729 PMCID: PMC5100644 DOI: 10.5037/jomr.2016.7304] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 09/07/2016] [Indexed: 12/28/2022]
Abstract
Objectives To systematically review risks of mechanical impact on peri-implant strain and prosthetic influence on stability across finite element studies. Material and Methods An online literature search was performed on MEDLINE and EMBASE databases published between 2011 and 2016. Following keywords tiered screening and selection of the title, abstract and full-text were performed. Studies of finite element analysis (FEA) were considered for inclusion that were written in English and revealed stress concentrations or strain at peri-implant bone level. Results There were included 20 FEA studies in total. Data were organized according to the following topics: bone layers, type of bone, osseointegration level, bone level, design of implant, diameter and length of implant, implant-abutment connection, type of supra-construction, loading axis, measurement units. The stress or strain at implant-bone contact was measured over all studies and numerical values estimated. Risks of overloading were accented as non-axial loading, misfits, cantilevers and the stability of peri-implant bone was related with the usage of platform switch connection of abutment. Conclusions Peri-implant area could be affected by non-axial loading, cantilever prosthetic elements, crown/implant ratio, type of implant-abutment connection, misfits, properties of restoration materials and antagonistic tooth. The heterogeneity of finite element analysis studies limits systematization of data. Results of these studies are comparable with other findings of in vitro, in vivo, prospective and retrospective studies.
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Affiliation(s)
- Julius Maminskas
- Department of Prosthodontics, Lithuanian Universty of Health Sciences, Kaunas Lithuania
| | | | - Ritva Kuoppala
- Prosthetic Dentistry and Stomatognathic Physiology, Research Unit of Oral Health Sciences, Faculty of Medicine, University of Oulu, Medical Research Center Oulu, Oulu University Hospital and University of Oulu Finland
| | - Aune Raustia
- Prosthetic Dentistry and Stomatognathic Physiology, Research Unit of Oral Health Sciences, Faculty of Medicine, University of Oulu, Medical Research Center Oulu, Oulu University Hospital and University of Oulu Finland
| | - Gintaras Juodzbalys
- Department of Maxillofacial Surgery, Lithuanian Universty of Health Sciences, Kaunas Lithuania
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Küçükkurt S, Alpaslan G, Kurt A. Biomechanical comparison of sinus floor elevation and alternative treatment methods for dental implant placement. Comput Methods Biomech Biomed Engin 2016; 20:284-293. [PMID: 27501343 DOI: 10.1080/10255842.2016.1218482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE In this study, we compared the success of sinus lifting and alternative treatment methods in applying dental implants in cases lacking adequate bone due to pneumatization of the maxillary sinus. METHODS In a computer environment, 3D models were created using computerized tomography data from a patient. Additionally, implants and abutments were scanned at the macroscopic level, and the resulting images were transferred to the 3D models. Five different models were examined: a control model, lateral sinus lifting (LSL), short dental implant placement (SIP), tilted implant placement (TIP) and distal prosthetic cantilever (DC) use. Vertical and oblique forces were applied in each model. The compression, tension and von Mises stresses in each model were analyzed by implementing a finite element analysis method. RESULTS In our study, the LSL method was observed to be the closest to the control model. The TIP model showed high stress values under conditions of oblique forces but showed successful results under conditions of vertical forces, and the opposite results were observed in the SIP model. The DC model provided the least successful results among all models. CONCLUSIONS Based on the results of this study, the LSL method should be the first choice among treatment options. Considering its successful results under conditions of oblique forces, the SIP method may be preferable to the TIP method. In contrast, every effort should be made to avoid the use of DCs.
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Affiliation(s)
- Sercan Küçükkurt
- a Faculty of Dentistry, Department of Oral and Maxillofacial Surgery , Istanbul Aydın University , Istanbul Turkey
| | - Gökhan Alpaslan
- b Faculty of Dentistry, Department of Oral and Maxillofacial Surgery , Gazi University , Ankara , Turkey
| | - Ahmet Kurt
- c Faculty of Engineering, Department of Manufacturing Engineering , Atılım University , Ankara , Turkey
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