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Gali S, Gururaja S, Karuveettil V, Janakiram C. Methodological approaches in graded dental ceramics: a scoping review protocol. JBI Evid Synth 2024; 22:1387-1392. [PMID: 38984562 PMCID: PMC7616240 DOI: 10.11124/jbies-23-00143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
OBJECTIVES This review will map the various methodological approaches used in graded dental ceramics and distinguish their material characteristics and properties. The aim is to identify gaps in the development and application of grading in dental ceramic systems. INTRODUCTION The advantage of functionally graded materials is the absence of the weakest link, with no distinct boundaries, thereby eliminating the possibility of stress concentrations at the interfaces. Functionally graded materials are well established in nature, such as in human teeth, bone, and the bio-tissues of plants and animals. This concept has also been explored in dental ceramics to enhance fatigue resistance and strength. INCLUSION CRITERIA This review will include observational studies and interventional studies, such as in vitro and experimental studies, on functionally graded dental ceramic systems. Studies that use finite element analysis to evaluate stress distributions, and studies on the mechanical performance of graded dental ceramics, irrespective of the type of ceramic material, design, or thickness of graded layers, will be considered. METHOD The review will follow the JBI methodology for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. MEDLINE (PubMed), Scopus, ProQuest Dissertations and Theses (EBSCOhost), Cochrane CENTRAL, and Google Scholar will be searched for English language studies. The search strategy will be based on MeSH terms and free-text specific terms, and will be adapted for each database. Two independent reviewers will screen titles and abstracts, and extract data from selected sources. The data extracted from the selected studies will be analyzed and presented in the form of tables and figures. REVIEW REGISTRATION Open Science Framework: https://osf.io/ahsp7.
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Affiliation(s)
- Sivaranjani Gali
- Department of Prosthodontics and Crown & Bridge, Faculty of Dental Sciences, M.S. Ramaiah University of Applied Sciences, Bangalore, India
| | - Suhasini Gururaja
- Department of Aerospace Engineering, Auburn University, Auburn, AL, USA
| | - Vineetha Karuveettil
- Amrita Center for Evidence-based Oral Health: A JBI Affiliated Group, Kerala, India
- Department of Public Health Dentistry, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kerala, India
| | - Chandrashekhar Janakiram
- Amrita Center for Evidence-based Oral Health: A JBI Affiliated Group, Kerala, India
- Department of Public Health Dentistry, Amrita School of Dentistry, Amrita Vishwa Vidyapeetham, Kerala, India
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Gali S, Gururaja S, Patel Z. Methodological approaches in graded dental ceramics. Dent Mater 2024; 40:e1-e13. [PMID: 38438282 PMCID: PMC7615955 DOI: 10.1016/j.dental.2024.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 01/05/2024] [Accepted: 02/12/2024] [Indexed: 03/06/2024]
Abstract
BACKGROUND Functionally graded materials (FGM) with indistinct boundaries potentially eliminate the damaging stresses occurring at the interfaces. FGM applications in dental ceramics have enhanced their fatigue resistance and interfacial toughness. OBJECTIVES This scoping review aims to map graded designs in dental ceramics, distinguish their methodological approaches with their material characteristics and properties, and understand the factors affecting the outcomes of each of the graded approaches. METHODS A systematic electronic search was performed with the databases MEDLINE (PubMed), Scopus, Cochrane Library, EBSCO, and Google Scholar along with a manual search. RESULTS About 2675 articles were initially found from all the searches with no date restriction till July 2023. After rejecting duplicates and based on exclusion criteria, about 52 articles were included. SIGNIFICANCE Methodological approaches in grading such as glass-infiltration and silica-infiltration have been investigated on pre-sintered zirconia. The type of infiltration and the method of infiltrate application significantly influenced the phase transformation of zirconia, its microstructure, surface hardness, fracture toughness, flexural strength, wear, and fatigue strength of graded dental zirconia. Interlayers were accommodated between metal-ceramic and veneer-core all-ceramic layers. Fractions of zirconia-porcelain and alumina-porcelain showed high bending strength and better stress distribution. The results of finite element analysis studies predicted that using 10-layered graded layers reduced the stresses at the crown-cement-dentin interface.
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Affiliation(s)
- Sivaranjani Gali
- Dept. of Prosthodontics, Faculty of Dental Sciences, M.S.Ramaiah University of Applied Sciences, Bangalore 560054, India.
| | | | - Zulekha Patel
- Dept. of Prosthodontics, Faculty of Dental Sciences, M.S.Ramaiah University of Applied Sciences, Bangalore 560054, India
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Rodrigues JVM, Cruz BS, Gomes MM, Campos TMB, Melo RM. Infiltration OF 5Y-PSZ with thermally compatible glass: Strength, microstructure and failure mode analyses. J Mech Behav Biomed Mater 2023; 142:105812. [PMID: 37084491 DOI: 10.1016/j.jmbbm.2023.105812] [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: 01/17/2023] [Revised: 03/22/2023] [Accepted: 03/26/2023] [Indexed: 04/23/2023]
Abstract
This study set out to develop a thermally compatible glass to be infiltrated into zirconia partially stabilized by yttrium oxide (5Y-PSZ), to characterize it, and to evaluate its structural reliability and mechanical behavior. 5Y-PSZ zirconia discs (N = 90), dimensions 1.5 mm × 15 mm were produced, polished with #600 alumina oxide and #1200 silicon carbide sandpaper in a polisher. Three groups of 5Y-PSZ discs were assigned (n = 30): Zctrl: as sintered zirconia, Zinf-comp: glass-infiltrated zirconia on the occlusal surface, and sintered, and Zinf-tens: glass-infiltrated zirconia on the cementing surface and sintered; for biaxial flexural strength testing (ISO 6872:2015). A gel was synthesized via the sol-gel method and applied to the ceramic surface. Mechanical assay data (MPa) were evaluated via Weibull analysis (α = 5%) and specimens via X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM), and fractographic analysis. The Zinf-tens group showed a characteristic strength of 824 MPa and m = 9.9; Zinf-comp 613 MPa and m = 10.2; Zctrl 534 MPa and m = 8; all groups differed statistically (σ0). However, they were similar in structural homogeneity (m). XRD showed 20-50 μm of infiltration, which means dissolution of part of the yttrium and reduction in the size of the cubic grains. In addition, the Zinf-tens group presented a failure origin from inside the material. The developed glass infiltrated into zirconia partially stabilized by yttrium oxide, increasing its characteristic strength and structural homogeneity by reducing surface defects and changing the failure mode.
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Affiliation(s)
- J V M Rodrigues
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology of São José Dos Campos, São Paulo State University (UNESP), São José Dos Campos, SP, Brazil
| | - B S Cruz
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology of São José Dos Campos, São Paulo State University (UNESP), São José Dos Campos, SP, Brazil
| | - M M Gomes
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology of São José Dos Campos, São Paulo State University (UNESP), São José Dos Campos, SP, Brazil
| | - T M B Campos
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of Sao Paulo, Bauru, SP, Brazil
| | - R M Melo
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology of São José Dos Campos, São Paulo State University (UNESP), São José Dos Campos, SP, Brazil.
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PEREIRA RM, RIBAS RG, MONTANHEIRO TLDA, SCHATKOSKI VM, RODRIGUES KF, KITO LT, KOBO LK, CAMPOS TMB, BONFANTE EA, GIERTHMUEHLEN PC, SPITZNAGEL FA, THIM GP. An engineering perspective of ceramics applied in dental reconstructions. J Appl Oral Sci 2023; 31:e20220421. [PMID: 36820784 PMCID: PMC9972857 DOI: 10.1590/1678-7757-2022-0421] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 01/04/2023] [Indexed: 02/22/2023] Open
Abstract
The demands for dental materials continue to grow, driven by the desire to reach a better performance than currently achieved by the available materials. In the dental restorative ceramic field, the structures evolved from the metal-ceramic systems to highly translucent multilayered zirconia, aiming not only for tailored mechanical properties but also for the aesthetics to mimic natural teeth. Ceramics are widely used in prosthetic dentistry due to their attractive clinical properties, including high strength, biocompatibility, chemical stability, and a good combination of optical properties. Metal-ceramics type has always been the golden standard of dental reconstruction. However, this system lacks aesthetic aspects. For this reason, efforts are made to develop materials that met both the mechanical features necessary for the safe performance of the restoration as well as the aesthetic aspects, aiming for a beautiful smile. In this field, glass and high-strength core ceramics have been highly investigated for applications in dental restoration due to their excellent combination of mechanical properties and translucency. However, since these are recent materials when compared with the metal-ceramic system, many studies are still required to guarantee the quality and longevity of these systems. Therefore, a background on available dental materials properties is a starting point to provoke a discussion on the development of potential alternatives to rehabilitate lost hard and soft tissue structures with ceramic-based tooth and implant-supported reconstructions. This review aims to bring the most recent materials research of the two major categories of ceramic restorations: ceramic-metal system and all-ceramic restorations. The practical aspects are herein presented regarding the evolution and development of materials, technologies applications, strength, color, and aesthetics. A trend was observed to use high-strength core ceramics type due to their ability to be manufactured by CAD/CAM technology. In addition, the impacts of COVID-19 on the market of dental restorative ceramics are presented.
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Affiliation(s)
- Raíssa Monteiro PEREIRA
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Renata Guimarães RIBAS
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Thaís Larissa do Amaral MONTANHEIRO
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Vanessa Modelski SCHATKOSKI
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Karla Faquine RODRIGUES
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Letícia Terumi KITO
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Lucas Kazunori KOBO
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Tiago Moreira Bastos CAMPOS
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
| | - Estevam Augusto BONFANTE
- Universidade de São PauloFaculdade de Odontologia de BauruDepartamento de Prótese e PeriodontiaBauruSPBrasilUniversidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Prótese e Periodontia, Bauru, SP, Brasil.
| | - Petra Christine GIERTHMUEHLEN
- Heinrich-Heine-UniversityMedical FacultyUniversity Hospital DüsseldorfDüsseldorfGermanyHeinrich-Heine-University, Medical Faculty and University Hospital Düsseldorf, Düsseldorf, Department of Prosthodontics, Germany.
| | - Frank Akito SPITZNAGEL
- Heinrich-Heine-UniversityMedical FacultyUniversity Hospital DüsseldorfDüsseldorfGermanyHeinrich-Heine-University, Medical Faculty and University Hospital Düsseldorf, Düsseldorf, Department of Prosthodontics, Germany.
| | - Gilmar Patrocínio THIM
- Instituto Tecnológico de AeronáuticaLaboratório de Plasma e ProcessosSão José dos CamposBrasilInstituto Tecnológico de Aeronáutica (ITA), Laboratório de Plasma e Processos (LPP), São José dos Campos, Brasil
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Bonfante EA, Calamita M, Bergamo ETP. Indirect restorative systems-A narrative review. J ESTHET RESTOR DENT 2023; 35:84-104. [PMID: 36688803 DOI: 10.1111/jerd.13016] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/24/2023]
Abstract
OBJECTIVE The background and clinical understanding of the properties of currently available indirect restorative systems and fabrication methods is, along with manufacturer and evidence-based literature, an important starting point to guide the clinical selection of materials for tooth and/or implant supported reconstructions. Therefore, this review explores most indirect restorative systems available in the market, especially all-ceramic, along with aspects of manufacturing process, clinical survival rates, and esthetic outcomes. OVERVIEW Progressive incorporation of new technologies in the dental field and advancements in materials science have enabled the development/improvement of indirect restorative systems and treatment concepts in oral rehabilitation, resulting in reliable and predictable workflows and successful esthetic and functional outcomes. Indirect restorative systems have evolved from metal ceramics and polymers to glass ceramics, polycrystalline ceramics, and resin-matrix ceramics, aiming to improve not only biological and mechanical properties, but especially the optical properties and esthetic quality of the reconstructions, in attempt to mimic natural teeth. CONCLUSIONS Based on several clinical research, materials, and patient-related parameters, a decision tree for the selection of indirect restorative materials was suggested to guide clinicians in the rehabilitation process. CLINICAL SIGNIFICANCE The pace of materials development is faster than that of clinical research aimed to support their use. Since no single material provides an ideal solution to every case, professionals must continuously seek information from well designed, long-term clinical trials in order to incorporate or not new materials and technological advancements.
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Affiliation(s)
- Estevam A Bonfante
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry - University of São Paulo, Bauru, SP, Brazil
| | - Marcelo Calamita
- Department of Restorative Dental Sciences at the University of Florida, Gainesville, Florida, USA
| | - Edmara T P Bergamo
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry - University of São Paulo, Bauru, SP, Brazil
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Alves LMM, Rodrigues CDS, Ramos NDC, Buizastrow J, Campos TMB, Bottino MA, Zhang Y, Melo RMD. Silica infiltration on translucent zirconia restorations: Effects on the antagonist wear and survivability. Dent Mater 2022; 38:2084-2095. [PMID: 36446649 PMCID: PMC9928576 DOI: 10.1016/j.dental.2022.11.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 09/23/2022] [Accepted: 11/11/2022] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To assess potential antagonist wear and survival probability of silica-infiltrated zirconia compared to glass-graded, glazed, and polished zirconia. METHODS Table top restorations made of 3Y-TZP (3Y), 5Y-PSZ (5Y), and lithium disilicate (LD) were bonded onto epoxy resin preparations. Each zirconia was divided into five groups according to the surface treatment: polishing; glaze; polishing-glaze; glass infiltration; and silica infiltration. The LD restorations received a glaze layer. Specimens were subjected to sliding fatigue wear using a steatite antagonist (1.25 ×106 cycles, 200 N). The presence of cracks, fractures, and/or debonding was checked every one/third of the total number of cycles was completed. Roughness, microstructural, Scanning electron microscopy, wear and residual stress analyses were conducted. Kaplan-Meier, Mantel-Cox (log-rank) and ANOVA tests were performed for statistical analyses. RESULTS The survival probability was different among the groups. Silica infiltration and polishing-glaze led to lower volume loss than glaze and glass-infiltration. Difference was observed for roughness among the zirconia and surface treatment, while lithium disilicate presented similar roughness compared to both glazed zirconia. Scanning electron microscopy revealed the removal of the surface treatment after sliding fatigue wear in all groups. Compressive stress was detected on 3Y surfaces, while tensile stress was observed on 5Y. SIGNIFICANCE 3Y and 5Y zirconia behaved similarly regarding antagonist wear, presenting higher antagonist wear than the glass ceramic. Silica-infiltrated and polished-glazed zirconia produced lower antagonist volume loss than glazed and glass-infiltrated zirconia. Silica-infiltrated 3Y and lithium disilicate restorations were the only groups to show survival probabilities lower than 85%.
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Affiliation(s)
- Larissa Marcia Martins Alves
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, Av. Eng. Francisco José Longo, 777, Jardim São Dimas, 12245-000 São José dos Campos, SP, Brazil; Department of Biomaterials and Biomimetics, New York University College of Dentistry, 433 1st Ave., New York, NY 10010, United States
| | - Camila da Silva Rodrigues
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, Av. Eng. Francisco José Longo, 777, Jardim São Dimas, 12245-000 São José dos Campos, SP, Brazil; Department of Biomaterials and Biomimetics, New York University College of Dentistry, 433 1st Ave., New York, NY 10010, United States
| | - Nathalia de Carvalho Ramos
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, Av. Eng. Francisco José Longo, 777, Jardim São Dimas, 12245-000 São José dos Campos, SP, Brazil
| | - Jeff Buizastrow
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, 433 1st Ave., New York, NY 10010, United States
| | - Tiago Moreira Bastos Campos
- Department of Physics, Aeronautics Technological Institute (ITA), Praça Marechal Eduardo Gomes, 50, 12228-900 São José dos Campos, SP, Brazil
| | - Marco Antonio Bottino
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, Av. Eng. Francisco José Longo, 777, Jardim São Dimas, 12245-000 São José dos Campos, SP, Brazil
| | - Yu Zhang
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, PA 19104, United States
| | - Renata Marques de Melo
- Department of Dental Materials and Prosthodontics, São Paulo State University (Unesp), Institute of Science and Technology, Av. Eng. Francisco José Longo, 777, Jardim São Dimas, 12245-000 São José dos Campos, SP, Brazil.
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Mohit KG, Lakha TA, Chinchwade A, Batul QA, Shaikh M, Kheur SM. Effects of surface modification techniques on zirconia substrates and their effect on bonding to dual cure resin cement - An in- vitro study. J Indian Prosthodont Soc 2022; 22:179-187. [PMID: 36511029 PMCID: PMC9132501 DOI: 10.4103/jips.jips_298_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Aim This study aims to evaluate the effect of different surface treatments of monolithic zirconia on the bond strength of resin to zirconia and, to explore alternative methods to improve this bonding. Settings and Design In-Vitro study. Materials and Methods Fifty rectangular sintered blocks of Yttria-stabilized Tetragonal Zirconia Polycrystal ceramics of dimensions were milled and sintered. These specimens were further divided into five groups (control, air abrasion, etching with primer application, air abrasion with primer application and novel glass infiltrated zirconia surface group), containing 10 samples each. The specimens were analyzed for surface roughness, tensile bond strength to resin cements, and adhesive and cohesive mode of failures. Statistical Analysis Used ANOVA and Post-Hoc Tukey test was perform to evaluate the significant differences in the mean values of the groups. Results Air-abraded samples showed the highest surface roughness (4.95 ± 0.65) (P < 0.05). The group with air abrasion followed by primer application showed the highest tensile bond strength (7.12 ± 0.69) (P < 0.05). The lowest surface roughness (0.638 ± 0.8093) and tensile bond strength (2.03 ± 0.58) was seen in samples that were subjected to etchant treatment followed by application of methacryloyloxydecyl di-hydrogen phosphate (MDP) primer. The changes in comparison to the control group were statistically insignificant (P > 0.05). Except Groups A (control) and C (etchant followed by primer), all other groups showed a cohesive failure. Conclusion Air abrasion of the zirconia surface with 50 μm alumina particles increases the surface roughness without damaging the surface. Air abrasion followed by MDP primer application is the recommended method of surface treatment to achieve superior bonding. Glass infiltration also showed promising results in terms of tensile bond strength.
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Affiliation(s)
- K. G. Mohit
- Department of and Prosthodontics and Implantology, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India,Address for correspondence: Dr. K. G. Mohit, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India. E-mail:
| | - Tabrez Amin Lakha
- Department of and Prosthodontics and Implantology, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India
| | - Aishwarya Chinchwade
- Department of and Prosthodontics and Implantology, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India
| | - Qamri A. Batul
- Department of Prosthodontics, Implantology and Maxillofacial Prosthetics, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India
| | - Mohsin Shaikh
- Department of and Prosthodontics and Implantology, M.A. Rangoonwala College of Dental Sciences and Research Centre, Pune, Maharashtra, India
| | - Supriya M. Kheur
- Department of Oral Pathology and Microbiology, D.Y. Patil Dental College, Pune, Maharashtra, India
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SHAFIGH ELNAZ, ASHRAFI MEHRAN. A REVIEW OF MECHANICAL BEHAVIOR OF DENTAL CERAMIC RESTORATIONS. J MECH MED BIOL 2021. [DOI: 10.1142/s0219519421500639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Dental ceramics are well known for restoring the function and aesthetic of lost or damaged teeth. Understanding these materials’ mechanical and aesthetic properties can make a suitable choice for those materials. The longevity of dental ceramics depends on several factors, including manufacturing method, clinical process, and the oral cavity’s aqueous environment. Failure mechanisms in restorative ceramics are complex and a combination of several factors. Different microstructures in the crystalline phase will involve the propagation of cracks and eventually the fatigue of ceramic materials. Large grains reduce mechanical performance compared to small grain sizes. Aesthetic materials used for veneering are weaker than the core materials and fail when even subjected to small loads. The soft bonding in the core–veneer interface and possible residual stresses created during the veneering method are drawbacks of these systems. Studies on the mechanical behavior of these materials have grown significantly in recent years and provide helpful information about static and fatigue experimentation and the failure behavior of various materials used in dental crowns.
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Affiliation(s)
- ELNAZ SHAFIGH
- Operative Dentistry Department, Faculty of Dentistry, AJA University of Medical Sciences, Tehran, Iran
| | - MEHRAN ASHRAFI
- Operative Dentistry Department, Faculty of Dentistry, AJA University of Medical Sciences, Tehran, Iran
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Prakash C, Kumar V, Mistri A, Uppal AS, Babbar A, Pathri BP, Mago J, Sharma A, Singh S, Wu LY, Zheng H. Investigation of Functionally Graded Adherents on Failure of Socket Joint of FRP Composite Tubes. MATERIALS 2021; 14:ma14216365. [PMID: 34771891 PMCID: PMC8585413 DOI: 10.3390/ma14216365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/06/2021] [Accepted: 10/11/2021] [Indexed: 11/30/2022]
Abstract
Fiber-reinforced polymer (FRP) matrix materials are quickly being investigated for application in concrete construction repair, reinforcement, and refurbishment. The technology has progressed to the point that its future acceptance is mainly reliant on the availability of established design guidelines based on recognized performance criteria, as well as the cost competitiveness of these technologies in contrast to conventional rehabilitation methods. The goal of this study is to evaluate the different functional grades of adhesives throughout bond length for bonded socket joints of laminated FRP composite pipes. Damage development resistance is high with a functionally graded FRP composite socket joint, as shown. To extend the service life of the structure, the joint designer should use an FRP composite socket joint with a functionally graded adhesive (FGA).
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Affiliation(s)
- Chander Prakash
- Department of Mechanical Engineering, Shandong University of Technology, Zibo 255000, China;
- School of Mechanical Engineering, Lovely Professional University, Phagwara 144001, India
- Correspondence: (C.P.); (L.Y.W.)
| | - Vidyapati Kumar
- Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur 721302, India;
| | - Ankita Mistri
- CSIR-Central Mechanical Engineering Research Institute, Durgapur 713209, India;
| | | | - Atul Babbar
- Department of Mechanical Engineering, Guru Gobind Singh Tricentenary University, Gurugram 122505, India;
| | | | - Jonty Mago
- Mechanical Engineering Department, Thapar Institute of Engineering and Technology, Patiala 147004, India;
| | - Ankit Sharma
- Chitkara College of Applied Engineering, Chitkara University, Rajpura 140401, India;
| | - Sunpreet Singh
- Department of Mechanical Engineering, Chandigarh University, Gharuan 140413, India;
| | - Linda Yongling Wu
- Department of Mechanical Engineering, Shandong University of Technology, Zibo 255000, China;
- Correspondence: (C.P.); (L.Y.W.)
| | - Hongyu Zheng
- Department of Mechanical Engineering, Shandong University of Technology, Zibo 255000, China;
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Trushkowsky RD, Medianti DR, Giotopoulos PL, Prathompat S, Zhang Y. Conservative Esthetic Replacement of a Missing Anterior Tooth Using Monolithic Zirconia One-Wing Fixed Dental Prosthesis. COMPENDIUM OF CONTINUING EDUCATION IN DENTISTRY (JAMESBURG, N.J. : 1995) 2021; 42:e9-e12. [PMID: 34606295 PMCID: PMC11303001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Advances in materials and adhesion technologies have enabled innovative, minimally invasive treatment for replacement of missing maxillary anterior teeth. In the first of two case reports presented, the treatment of a 17-year-old female patient with a missing right central incisor is described. The patient had internal resorption of tooth No. 8, which needed to be extracted prior to a LeFort osteotomy because retention of the tooth may have compromised the healing. The patient was told she could not have an implant placed until she was 25 years old. Treatment options, thus, included a provisional removable appliance (flipper), an Essix appliance, or a resin-bonded one-wing zirconia bridge with only slight modification to the left central incisor. The second case report describes an adult male patient who had had a deciduous canine extracted and wanted a replacement for missing No. 11. In demonstrating minimally invasive treatment to replace a missing maxillary anterior tooth, this article shows how the use of a graded zirconia wing allows bonding with conventional techniques.
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Affiliation(s)
- Richard D Trushkowsky
- Adjunct Clinical Professor, Department Cariology and Comprehensive Care, Associate Director, International Program in Advanced Esthetic Dentistry, New York University College of Dentistry (NYUCD), New York, New York
| | - Dhanny R Medianti
- Fellow, NYUCD International Program in Advanced Esthetic Dentistry, New York, New York
| | - Paul L Giotopoulos
- Adjunct Clinical Instructor, Department Cariology and Comprehensive Care, NYUCD, New York, New York
| | - Siriwadee Prathompat
- Resident, NYUCD International Program in Advanced Esthetic Dentistry, New York, New York
| | - Yu Zhang
- Professor, Department of Preventive and Restorative Sciences, Director for Restorative Research, University of Pennsylvania, School of Dental Medicine, Philadelphia, Pennsylvania
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11
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Kamboj N, Ressler A, Hussainova I. Bioactive Ceramic Scaffolds for Bone Tissue Engineering by Powder Bed Selective Laser Processing: A Review. MATERIALS 2021; 14:ma14185338. [PMID: 34576562 PMCID: PMC8469313 DOI: 10.3390/ma14185338] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/02/2021] [Accepted: 09/12/2021] [Indexed: 02/07/2023]
Abstract
The implementation of a powder bed selective laser processing (PBSLP) technique for bioactive ceramics, including selective laser sintering and melting (SLM/SLS), a laser powder bed fusion (L-PBF) approach is far more challenging when compared to its metallic and polymeric counterparts for the fabrication of biomedical materials. Direct PBSLP can offer binder-free fabrication of bioactive scaffolds without involving postprocessing techniques. This review explicitly focuses on the PBSLP technique for bioactive ceramics and encompasses a detailed overview of the PBSLP process and the general requirements and properties of the bioactive scaffolds for bone tissue growth. The bioactive ceramics enclosing calcium phosphate (CaP) and calcium silicates (CS) and their respective composite scaffolds processed through PBSLP are also extensively discussed. This review paper also categorizes the bone regeneration strategies of the bioactive scaffolds processed through PBSLP with the various modes of functionalization through the incorporation of drugs, stem cells, and growth factors to ameliorate critical-sized bone defects based on the fracture site length for personalized medicine.
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Affiliation(s)
- Nikhil Kamboj
- Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia;
| | - Antonia Ressler
- Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev Trg 19, p.p.177, HR-10001 Zagreb, Croatia;
| | - Irina Hussainova
- Department of Mechanical and Industrial Engineering, Tallinn University of Technology, Ehitajate Tee 5, 19086 Tallinn, Estonia;
- Correspondence:
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12
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Chen J, Jian Y, Chen S, Wang X, Dao L, Zhao K. Establishment of optimal variable elastic modulus distribution in the design of full-crown restorations by finite element analysis. Dent Mater J 2021; 40:1403-1409. [PMID: 34261832 DOI: 10.4012/dmj.2021-053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To establish optimal elastic modulus distribution throughout the entire all-ceramic crown, aiming at improvement of the mechanical properties of the restoration as well as the adhesive interface, seven 3D models of mandibular first premolars of zirconia monolithic and bilayer crowns and lithium disilicate monolithic and bilayer crowns were constructed. The elastic modulus distribution of 8-layer crown A referred to human enamel, B was calculated by a genetic algorithm (GA) to minimize the principle stresses on the crown, and C minimized the shear stresses at the cementing lines. After applying a static load of 600 N, the maximum principle stresses were calculated and analyzed by finite element analysis (FEA). Group C were found to have the lowest peak shear stress at the cementing line and moderate peak tensile stress in the crown. Introduction of the modified elastic modulus distribution from human enamel into the entire all-ceramic crown reinforces the mechanical properties of the whole restoration as well as the adhesive interface against chipping and debonding.
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Affiliation(s)
- Jianghai Chen
- Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University.,Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University
| | - Yutao Jian
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University.,Institute of Stomatological Research, Sun Yat-sen University
| | - Shumin Chen
- Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University.,Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University
| | - Xiaodong Wang
- Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University.,Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University
| | - Li Dao
- Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University.,Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University
| | - Ke Zhao
- Hospital of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University.,Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University
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13
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Fabris D, Fredel MC, Souza JCM, Silva FS, Henriques B. Biomechanical behavior of functionally graded S53P4 bioglass-zirconia dental implants: Experimental and finite element analyses. J Mech Behav Biomed Mater 2021; 120:104565. [PMID: 34087536 DOI: 10.1016/j.jmbbm.2021.104565] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The aim of this work was to evaluate the biomechanical behavior of one-piece zirconia implants with a functionally graded bioglass (BG) layer as compared to monolithic zirconia and BG-coated implants, using the finite element method (FEM). METHODS Zirconia disks were infiltrated with bioglass S53P4 and then morphologically inspected by scanning electron microscopy (SEM) followed by mechanical analyses on micro-indentation tests for further biomechanical validation using the finite element method (FEM). On modeling, zirconia dental implants anchored into mandibular bone were simulated on occlusal loading as recorded under mastication. Three types of implants were simulated: i) free of BG coating, ii) with 100 μm or 150 μm thick conventional BG coatings; and iii) with graded BG coatings involving 3 different chemical composition distributions. The stress state at both implant and bone were evaluated using the FEM. The mechanically-induced bone remodelling was analyzed through the bone strain results. RESULTS Infiltration of BG into a zirconia structure resulted in a ∼100 μm thick layer with an exponential-like gradation of chemical composition and properties. Regarding the FEM calculations, the BG coating induced up to 30% decrease on stress in the implant body when compared to the monolithic zirconia implant. The gradient of chemical composition also improved the stresses' distribution. The stresses distribution towards the BG-coatings were significantly high and could lead to failure. Stresses on the bone were recorded down to its strength threshold, with insignificant influence of the coating layer. The bone strain values on all models indicates further bone remodelling although BG-coated and BG-graded zirconia implants showed the highest strain magnitude that may enhance the mechanical stimulation for bone maintenance. SIGNIFICANCE Graded BG-zirconia dental implants showed enhanced overall biomechanical behaviour as compared to the BG-coated or monolithic zirconia dental implants. Also, such biomechanical improvements noticed for the BG-graded system should be considered in combination with the well-known osseointegration benefits of bioactive glasses.
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Affiliation(s)
- Douglas Fabris
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900, Florianópolis, SC, Brazil
| | - Márcio C Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900, Florianópolis, SC, Brazil
| | - Júlio C M Souza
- Department of Dental Sciences, University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra PRD, Portugal; CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal
| | - Filipe S Silva
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal
| | - Bruno Henriques
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900, Florianópolis, SC, Brazil; Department of Dental Sciences, University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra PRD, Portugal; School of Dentistry (DODT), Postgraduate Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis, SC, Brazil.
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14
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Dai T, Yu Z, Yuan S, Zou H, Liu P. Gradient structure polyimide/graphene composite aerogels fabricated by
layer‐by‐layer
assembly and unidirectional freezing. J Appl Polym Sci 2021. [DOI: 10.1002/app.50153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Tianwen Dai
- State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University Chengdu China
| | - Zhi Yu
- State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University Chengdu China
| | - Shuaiwei Yuan
- State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University Chengdu China
| | - Huawei Zou
- State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University Chengdu China
| | - Pengbo Liu
- State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan University Chengdu China
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15
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Fathy SM, Al-Zordk W, E Grawish M, V Swain M. Flexural strength and translucency characterization of aesthetic monolithic zirconia and relevance to clinical indications: A systematic review. Dent Mater 2021; 37:711-730. [PMID: 33581910 DOI: 10.1016/j.dental.2021.01.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/15/2020] [Accepted: 01/20/2021] [Indexed: 02/04/2023]
Affiliation(s)
- Salma M Fathy
- Dental Biomaterials Department, Faculty of Oral and Dental Medicine, Zagazig University, Zagazig, Egypt.
| | - Walid Al-Zordk
- Fixed Prosthodontics Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Mohammed E Grawish
- Oral Biology Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt
| | - Micheal V Swain
- Discipline of Biomaterials, Faculty of Dentistry, University of Sydney, Australia
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16
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Micro and Macro-Tribology Behavior of a Hierarchical Architecture of a Multilayer TaN/Ta Hard Coating. COATINGS 2020. [DOI: 10.3390/coatings10030263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The micro- and macro-tribological behaviors of a novel hierarchical TaN/Ta coating deposited on Ti6Al4V biomedical alloy by direct current magnetron sputtering were analyzed in the present work. This analysis was associated with the morphological, structural, and mechanical properties, as well as the roughness changes during and after the tribological tests. The wear track of the coating after the macro-tribology tests was evaluated by Raman spectroscopy in order to detect the compounds formed as a result of the tribo-reactions that occurred during the tests. Micro- and macro-tribology behaviors showed a significant wear rate reduction of the hierarchical coating in comparison to the Ti6Al4V substrate. For the case of the micro-tribology tests, this reduction was attributed to the high hardness of the coating (31.4 GPa); however, this hardness caused a considerable increment in the friction coefficient. On the other hand, the macro-tribology performance was associated with the hardness and the ability of the hierarchical architecture to prevent the propagation of cracks. Moreover, the friction coefficient increased considerably at the end of the test; this increment was associated with the tantalum oxides in the wear track detected by Raman spectroscopy.
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17
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Pérez-Barrera J, Figueroa A, Vázquez F. Controlling and Optimizing Entropy Production in Transient Heat Transfer in Graded Materials. ENTROPY 2019; 21:e21050463. [PMID: 33267177 PMCID: PMC7514952 DOI: 10.3390/e21050463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 04/22/2019] [Accepted: 04/24/2019] [Indexed: 11/16/2022]
Abstract
This paper presents a numerical analysis of the transient heat transfer problem arising when a functionally graded material is subjected to a fixed temperature difference. Varying the gradation of the system, the thermal performance of the material is assessed both in time-dependent and steady-state conditions by means of temperature profiles and entropy production. One of the main contributions of this paper is the analysis of the system in the transient, from which it is found that the entropy production has a non-monotonic behaviour since maximum and minimum values of this physical quantity could be identified by varying the grading profile of the material. The latter allows to propose an optimization criterion for functionally graded materials which consists of the identification of spatial regions where temperature gradients are large and find thermal conductivity profiles that attenuate those gradients, thus reducing the thermal stresses present inside the material.
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Affiliation(s)
- James Pérez-Barrera
- Centro de Investigación en Ciencias (CInC), Universidad Autónoma del Estado de Morelos (UAEM), Av. Universidad 1001, Col. Chamilpa, Cuernavaca 62209, Mexico
| | - Aldo Figueroa
- CONACyT—Centro de Investigación en Ciencias (CInC), Universidad Autónoma del Estado de Morelos (UAEM), Av. Universidad 1001, Col. Chamilpa, Cuernavaca 62209, Mexico
- Correspondence:
| | - Federico Vázquez
- Energy Engineering Department, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Müegyetem rkp. 9 D. 208, H-1111 Budapest, Hungary
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18
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Madeira S, Mesquita-Guimarães J, Ribeiro P, Fredel M, Souza JCM, Soares D, Silva FS, Henriques B. Y-TZP/porcelain graded dental restorations design for improved damping behavior - A study on damping capacity and dynamic Young's modulus. J Mech Behav Biomed Mater 2019; 96:219-226. [PMID: 31055212 DOI: 10.1016/j.jmbbm.2019.04.033] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 01/12/2023]
Abstract
The development of dental restorative materials that mimic tooth-like properties provided by graded structures, aesthetics and properties such as strength, damping capacity and the ability for a continuous remodeling according to the biomechanical solicitation is a great challenge. In this work, damping capacity and dynamic Young's modulus of Y-TZP/porcelain composites for all-ceramic dental restorations were studied. These mechanical properties were assessed by dynamic mechanical analyses (DMA) at frequencies of 1, 5 and 10 Hz, over a temperature ranging from 0 to 60 °C, simulating extreme conditions when a cold or hot drink is experienced. The results showed that porcelain and porcelain-matrix composites exhibited higher damping capacity while Y-TZP and Y-TZP-matrix composites presented higher dynamic Young's modulus. Furthermore, while damping capacity is strongly influenced by the temperature, no significant difference in dynamic Young's modulus was found. For both damping and modulus properties, no significant influence of frequency was found for the tested materials. Based on the obtained results and also on the known advantages of the graded Y-TZP/porcelain structures over traditional bi-layer solutions (e.g., improved bending strength, enhanced mechanical and thermal stress distribution), a novel design of all-ceramic restoration with damping capacity has been proposed at the end of this study. A positive impact on the long-term performance of these all-ceramic restorations may be expected.
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Affiliation(s)
- S Madeira
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal.
| | - J Mesquita-Guimarães
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal.
| | - P Ribeiro
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal
| | - M Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis, SC, Brazil
| | - J C M Souza
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal; Department of Dental Sciences, University Institute of Health Sciences (IUCS), CESPU, Gandra, Portugal
| | - D Soares
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal
| | - F S Silva
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal
| | - Bruno Henriques
- Center for Micro-Electro Mechanical Systems (CMEMS), University of Minho, Campus de Azurém, 4800-058, Guimarães, Portugal; Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis, SC, Brazil; School of Dentistry (DODT), Post-Graduate Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis, SC, Brazil.
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19
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Roedel S, Mesquita-Guimarães J, Souza JCM, Silva FS, Fredel MC, Henriques B. Production and characterization of zirconia structures with a porous surface. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 101:264-273. [PMID: 31029319 DOI: 10.1016/j.msec.2019.03.087] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 02/07/2019] [Accepted: 03/24/2019] [Indexed: 12/21/2022]
Abstract
The aim of this study was to produce zirconia structures with a porous surface by the dip coating technique and assess the mechanical properties of the structures as well as the integrity of the porous layers. Surface porous layers with homogenous and graded porosity were produced over zirconia substrate discs using zirconia powders with different average sizes (d50 = 40 μm; d50 = 70 μm and d50 = 100 μm) and without pore forming fugitive phases. Specimens were inspected using Scanning Electron Microscopy. Bending strength of specimens was obtained from biaxial flexural tests (B3B). Porous layers were successfully produced on zirconia discs substrates and the bending strength of these specimens were ~35% lower than uncoated specimens. Delamination occurred especially in layers with higher thickness and made of bigger particles. Practical application examples were provided in this paper showing the versatility of these porous surfaces in the production of multifunctional surfaces for stronger interfaces.
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Affiliation(s)
- Stephanie Roedel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC, Brazil.
| | | | - Júlio C M Souza
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal; School of Dentistry, Polythenic Institute of Healh Sciences of North (IUCS-CESPU), Gandra, Portugal
| | - Filipe S Silva
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
| | - Márcio C Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC, Brazil; School of Dentistry, Polythenic Institute of Healh Sciences of North (IUCS-CESPU), Gandra, Portugal
| | - Bruno Henriques
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC, Brazil; CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal; School of Dentistry (DODT), Post-Graduation Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900 Florianópolis, SC, Brazil.
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20
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Schünemann FH, Galárraga-Vinueza ME, Magini R, Fredel M, Silva F, Souza JCM, Zhang Y, Henriques B. Zirconia surface modifications for implant dentistry. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 98:1294-1305. [PMID: 30813009 DOI: 10.1016/j.msec.2019.01.062] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 01/13/2019] [Accepted: 01/14/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Zirconia has emerged as a versatile dental material due to its excellent aesthetic outcomes such as color and opacity, unique mechanical properties that can mimic the appearance of natural teeth and decrease peri-implant inflammatory reactions. OBJECTIVE The aim of this review was to critically explore the state of art of zirconia surface treatment to enhance the biological and osseointegration behavior of zirconia in implant dentistry. MATERIALS AND METHODS An electronic search in PubMed database was carried out until May 2018 using the following combination of key words and MeSH terms without time periods: "zirconia surface treatment" or "zirconia surface modification" or "zirconia coating" and "osseointegration" or "biological properties" or "bioactivity" or "functionally graded properties". RESULTS Previous studies have reported the influence of zirconia-based implant surface on the adhesion, proliferation, and differentiation of osteoblast and fibroblasts at the implant to bone interface during the osseointegration process. A large number of physicochemical methods have been used to change the implant surfaces and therefore to improve the early and late bone-to-implant integration, namely: acid etching, gritblasting, laser treatment, UV light, CVD, and PVD. The development of coatings composed of silica, magnesium, graphene, dopamine, and bioactive molecules has been assessed although the development of a functionally graded material for implants has shown encouraging mechanical and biological behavior. CONCLUSION Modified zirconia surfaces clearly demonstrate faster osseointegration than that on untreated surfaces. However, there is no consensus regarding the surface treatment and consequent morphological aspects of the surfaces to enhance osseointegration.
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Affiliation(s)
- Fernanda H Schünemann
- School of Dentistry (DODT), Post-Graduate Program in Dentistry (PPGO), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900 Florianópolis, SC, Brazil
| | - María E Galárraga-Vinueza
- School of Dentistry (DODT), Post-Graduate Program in Dentistry (PPGO), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900 Florianópolis, SC, Brazil
| | - Ricardo Magini
- School of Dentistry (DODT), Post-Graduate Program in Dentistry (PPGO), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900 Florianópolis, SC, Brazil
| | - Márcio Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900, Florianópolis, SC, Brazil
| | - Filipe Silva
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
| | - Júlio C M Souza
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal; Department of Dental Sciences, University Institute of Health Sciences (IUCS), CESPU, 4585-116, Gandra, Portugal
| | - Yu Zhang
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, NYU, New York, NY 10010, USA
| | - Bruno Henriques
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, 88040-900, Florianópolis, SC, Brazil; CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal.
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21
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Sun T, Liu R, Liu X, Feng X, Zhang Y, Lai R. The Biocompatibility of Dental Graded Nano-Glass-Zirconia Material After Aging. NANOSCALE RESEARCH LETTERS 2018; 13:61. [PMID: 29473113 PMCID: PMC5823795 DOI: 10.1186/s11671-018-2479-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 02/14/2018] [Indexed: 06/08/2023]
Abstract
ᅟ: A graded nano-glass/zirconia (G/Z) system has been developed via the infiltration of nano-glass into a nano-zirconia surface, which is advantageous for robust core-veneer bonds. The aging issue is a key for yttrium-stabilized tetragonal zirconia polycrystals (Y-TZPs), and therefore, it is necessary to evaluate the influence of aging degradation on the biocompatibility of G/Z systems before their possible clinical application. Herein, such biocompatibility testing was performed with human gingival fibroblasts (HGFs) seeded onto unaged/aged G/Z and Y-TZP for 2-72 h. Assessments included an oral mucous membrane irritation test in conjunction with analyses of cell viability, cell adhesion, and oxidative stress responses. Significant metabolic decreases in aged G/Z- and Y-TZP-treated cells were observed at 72 h. G/Z did not elicit any significant differences in cell viability compared with Y-TZP over 72 h both before and after aging. The oxidative stress data for the aged G/Z- and Y-TZP-treated cells showed a significant increase at 72 h. The G/Z specimens did not elicit any significant differences in ROS production compared with Y-TZP over 72 h both before and after aging. The cell adhesion rates of both G/Z and Y-TZP increased significantly after aging. The cell adhesion rates of G/Z and Y-TZP were not significantly different before and after aging. According to the oral mucous membrane irritation test, scores for macroscopic and microscopic observations for both the aged G/Z and unaged G/Z sides were 0, demonstrating no consequent irritation. CONCLUSIONS The excellent biocompatibility of G/Z indicates that it has potential for future clinical applications.
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Affiliation(s)
- Ting Sun
- Medical Center of Stomatology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China
| | - Ruoyu Liu
- Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, 518033, China
| | - Xiangning Liu
- Medical Center of Stomatology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China
| | - Xiaoli Feng
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Yanli Zhang
- Department of Stomatology, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China
| | - Renfa Lai
- Medical Center of Stomatology, The First Affiliated Hospital of Jinan University, Guangzhou, 510630, China.
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Askari E, Flores P, Silva F. A particle swarm-based algorithm for optimization of multi-layered and graded dental ceramics. J Mech Behav Biomed Mater 2018; 77:461-469. [DOI: 10.1016/j.jmbbm.2017.10.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/27/2017] [Accepted: 10/02/2017] [Indexed: 10/18/2022]
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Using glass-graded zirconia to increase delamination growth resistance in porcelain/zirconia dental structures. Dent Mater 2017; 34:e8-e14. [PMID: 29183670 DOI: 10.1016/j.dental.2017.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 09/04/2017] [Accepted: 11/08/2017] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Porcelain fused to zirconia (PFZ) restorations are widely used in prosthetic dentistry. However, their tendency to delaminate along the P/Z interface remains a practical problem so that assessing and improving the interfacial strength are important design aspects. This work examines the effect of modifying the zirconia veneering surface with an in-house felspathic glass on the interfacial fracture resistance of fused P/Z. METHODS Three material systems are studied: porcelain fused to zirconia (control) and porcelain fused to glass-graded zirconia with and without the presence of a glass interlayer. The specimens were loaded in a four-point-bend fixture with the porcelain veneer in tension. The evolution of damage is followed with the aid of a video camera. The interfacial fracture energy GC was determined with the aid of a FEA, taking into account the stress shielding effects due to the presence of adjacent channel cracks. RESULTS Similarly to a previous study on PFZ specimens, the fracture sequence consisted of unstable growth of channel cracks in the veneer followed by stable cracking along the P/Z interface. However, the value of GC for the graded zirconia was approximately 3 times that of the control zirconia, which is due to the good adhesion between porcelain and the glass network structure on the zirconia surface. SIGNIFICANCE Combined with its improved bonding to resin-based cements, increased resistance to surface damage and good esthetic quality, graded zirconia emerges as a viable material concept for dental restorations.
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Abstract
A survey of the development of dental ceramics is presented to provide a better understanding of the rationale behind the development and clinical indications of each class of ceramic material. Knowledge of the composition, microstructure, and properties of a material is critical for selecting the right material for specific applications. The key to successful ceramic restorations rests on material selection, manufacturing technique, and restoration design, including the balancing of several factors such as residual stresses, tooth contact conditions, tooth size and shape, elastic modulus of the adhesives and tooth structure, and surface state.
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Affiliation(s)
- Yu Zhang
- Department of Biomaterials and Biomimetics, NYU College of Dentistry, 433 First Avenue, Room 810, New York, NY 10010, USA.
| | - J Robert Kelly
- Department of Biomedical Engineering, University of Connecticut Health Center, Mailstop 1615, 263 Farmington Avenue, Farmington, CT 06030-1615, USA
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Vu VT, Oh GJ, Yun KD, Lim HP, Kim JW, Nguyen TPT, Park SW. Acid etching of glass-infiltrated zirconia and its biological response. J Adv Prosthodont 2017; 9:104-109. [PMID: 28435619 PMCID: PMC5397586 DOI: 10.4047/jap.2017.9.2.104] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 12/05/2016] [Accepted: 12/20/2016] [Indexed: 11/18/2022] Open
Abstract
PURPOSE The purpose of this study was to evaluate the influence of acid etching treatment on surface characteristics and biological response of glass-infiltrated zirconia. MATERIALS AND METHODS A hundred zirconia specimens were divided into four groups depending on surface treatments: untreated zirconia (group Z); acid-etched zirconia (group ZE); glass-infiltrated zirconia (group ZG); and glass-infiltrated and acid-etched zirconia (group ZGE). Surface roughness, surface topography, surface morphology, and Vickers hardness of specimens were evaluated. For biological response test, MC3T3-E1 cell attachment and proliferation on surface of the specimens were examined. The data were statistically analyzed using one-way ANOVA and Tukey's HSD test at a significance level of 0.05. RESULTS Group ZGE showed the highest surface roughness (Ra = 1.54 µm) compared with other groups (P < .05). Meanwhile, the hardness of group Z was significantly higher than those of other groups (P < .05). Cell attachment and cell proliferation were significantly higher in group ZGE (P < .05). CONCLUSION We concluded that effective surface roughness on zirconia could be made by acid etching treatment after glass infiltration. This surface showed significantly enhanced osteoblast cell response.
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Affiliation(s)
- Van Thi Vu
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Gye-Jeong Oh
- RIS Foundation for Advanced Biomaterial, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Kwi-Dug Yun
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Hyun-Pil Lim
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Ji-Won Kim
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Thao Phuong Thi Nguyen
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Sang-Won Park
- Department of Prosthodontics, Dental Science Research Institute, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
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Fabris D, Souza JC, Silva FS, Fredel M, Mesquita-Guimarães J, Zhang Y, Henriques B. THERMAL RESIDUAL STRESSES IN BILAYERED, TRILAYERED AND GRADED DENTAL CERAMICS. CERAMICS INTERNATIONAL 2017; 43:3670-3678. [PMID: 28163345 PMCID: PMC5289668 DOI: 10.1016/j.ceramint.2016.11.209] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Layered ceramic systems are usually hit by residual thermal stresses created during cooling from high processing temperature. The purpose of this study was to determine the thermal residual stresses at different ceramic multi-layered systems and evaluate their influence on the bending stress distribution. Finite elements method was used to evaluate the residual stresses in zirconia-porcelain and alumina-porcelain multi-layered discs and to simulate the 'piston-on-ring' test. Temperature-dependent material properties were used. Three different multi-layered designs were simulated: a conventional bilayered design; a trilayered design, with an intermediate composite layer with constant composition; and a graded design, with an intermediate layer with gradation of properties. Parameters such as the interlayer thickness and composition profiles were varied in the study. Alumina-porcelain discs present smaller residual stress than the zirconia-porcelain discs, regardless of the type of design. The homogeneous interlayer can yield a reduction of ~40% in thermal stress relative to bilayered systems. Thinner interlayers favoured the formation of lower thermal stresses. The graded discs showed the lowest thermal stresses for a gradation profile given by power law function with p=2. The bending stresses were significantly affected by the thermal stresses in the discs. The risk of failure for all-ceramic dental restorative systems can be significantly reduced by using trilayered systems (homogenous or graded interlayer) with the proper design.
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Affiliation(s)
- Douglas Fabris
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Júlio C.M. Souza
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
- School of Dentistry (DODT), Post-Graduation Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis/SC, Brazil
| | - Filipe S. Silva
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
| | - Márcio Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Joana Mesquita-Guimarães
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Yu Zhang
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York University, New York, USA
| | - Bruno Henriques
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
- School of Dentistry (DODT), Post-Graduation Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis/SC, Brazil
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Influence of interlayer design on residual thermal stresses in trilayered and graded all-ceramic restorations. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 71:1037-1045. [PMID: 27987657 DOI: 10.1016/j.msec.2016.11.087] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 10/24/2016] [Accepted: 11/23/2016] [Indexed: 11/21/2022]
Abstract
Residual thermal stresses are formed in dental restorations during cooling from high temperature processing. The aim of this study was to evaluate the influence of constructive design variables (composition and interlayer thickness) on residual stresses in alumina- and zirconia-graded restorations. Restorations' real-like cooling conditions were simulated using finite elements method and temperature-dependent material properties were used. Three different designs were evaluated: a bilayered restoration (sharp transition between materials); a trilayered restoration with a homogenous interlayer between core and veneer; and a trilayered restoration with a graded interlayer. The interlayer thickness and composition were varied. Zirconia restorations presented overall higher thermal stress values than alumina ones. Thermal stresses were significantly reduced by the presence of a homogeneous interlayer. The composition of the interlayer showed great influence on the thermal stresses, with the best results for homogeneous interlayers being observed for porcelain contents in the composite ranging between 30%-50% (vol.%), for both alumina and zirconia restorations. The interlayer's thickness showed a minor contribution in the thermal stress reduction. The graded interlayer showed an optimized reduction in restorations' thermal stresses. The use of graded interlayer, favoring enhanced thermal stress distributions and lower magnitude is expected to reduce the risk of catastrophic failure.
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Functionally graded materials for orthopedic applications – an update on design and manufacturing. Biotechnol Adv 2016; 34:504-531. [DOI: 10.1016/j.biotechadv.2015.12.013] [Citation(s) in RCA: 179] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 12/26/2022]
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Shear bond strength of veneering porcelain to zirconia: Effect of surface treatment by CNC-milling and composite layer deposition on zirconia. J Mech Behav Biomed Mater 2016; 60:547-556. [DOI: 10.1016/j.jmbbm.2016.03.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/17/2016] [Accepted: 03/17/2016] [Indexed: 11/20/2022]
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Fabris D, Souza JC, Silva FS, Fredel M, Mesquita-Guimarães J, Zhang Y, Henriques B. The bending stress distribution in bilayered and graded zirconia-based dental ceramics. CERAMICS INTERNATIONAL 2016; 42:11025-11031. [PMID: 28104926 PMCID: PMC5241077 DOI: 10.1016/j.ceramint.2016.03.245] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The purpose of this study was to evaluate the biaxial flexural stresses in classic bilayered and in graded zirconia-feldspathic porcelain composites. A finite element method and an analytical model were used to simulate the piston-on-ring test and to predict the biaxial stress distributions across the thickness of the bilayer and graded zirconia-feldspathic porcelain discs. An axisymmetric model and a flexure formula of Hsueh et al. were used in the FEM and analytical analysis, respectively. Four porcelain thicknesses were tested in the bilayered discs. In graded discs, continuous and stepwise transitions from the bottom zirconia layer to the top porcelain layer were studied. The resulting stresses across the thickness, measured along the central axis of the disc, for the bilayered and graded discs were compared. In bilayered discs, the maximum tensile stress decreased while the stress mismatch (at the interface) increased with the porcelain layer thickness. The optimized balance between both variables is achieved for a porcelain thickness ratio in the range of 0.30-0.35. In graded discs, the highest tensile stresses were registered for porcelain rich interlayers (p=0.25) whereas the zirconia rich ones (p=8) yield the lowest tensile stresses. In addition, the maximum stresses in a graded structure can be tailored by altering compositional gradients. A decrease in maximum stresses with increasing values of p (a scaling exponent in the power law function) was observed. Our findings showed a good agreement between the analytical and simulated models, particularly in the tensile region of the disc. Graded zirconia-feldspathic porcelain composites exhibited a more favourable stress distribution relative to conventional bilayered systems. This fact can significantly impact the clinical performance of zirconia-feldspathic porcelain prostheses, namely reducing the fracture incidence of zirconia and the chipping and delamination of porcelain.
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Affiliation(s)
- Douglas Fabris
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Júlio C.M. Souza
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
- School of Dentistry (DODT), Post-Graduation Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis/SC, Brazil
| | - Filipe S. Silva
- CMEMS-UMinho, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal
| | - Márcio Fredel
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Joana Mesquita-Guimarães
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
| | - Yu Zhang
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York University, New York, USA
| | - Bruno Henriques
- Ceramic and Composite Materials Research Group (CERMAT), Federal University of Santa Catarina (UFSC), Campus Trindade, Florianópolis/SC, Brazil
- School of Dentistry (DODT), Post-Graduation Program in Dentistry (PPGO), Federal University of Santa Catarina, Campus Trindade, 88040-900, Florianópolis/SC, Brazil
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Madfa AA, Yue XG. Dental prostheses mimic the natural enamel behavior under functional loading: A review article. JAPANESE DENTAL SCIENCE REVIEW 2016; 52:2-13. [PMID: 28408950 PMCID: PMC5382785 DOI: 10.1016/j.jdsr.2015.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/18/2015] [Accepted: 07/23/2015] [Indexed: 11/30/2022] Open
Abstract
Alumina- and zirconia-based ceramic dental restorations are designed to repair functionality as well as esthetics of the failed teeth. However, these materials exhibited several performance deficiencies such as fracture, poor esthetic properties of ceramic cores (particularly zirconia cores), and difficulty in accomplishing a strong ceramic–resin-based cement bond. Therefore, improving the mechanical properties of these ceramic materials is of great interest in a wide range of disciplines. Consequently, spatial gradients in surface composition and structure can improve the mechanical integrity of ceramic dental restorations. Thus, this article reviews the current status of the functionally graded dental prostheses inspired by the dentino-enamel junction (DEJ) structures and the linear gradation in Young's modulus of the DEJ, as a new material design approach, to improve the performance compared to traditional dental prostheses. This is a remarkable example of nature's ability to engineer functionally graded dental prostheses. The current article opens a new avenue for recent researches aimed at the further development of new ceramic dental restorations for improving their clinical durability.
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Affiliation(s)
- Ahmed A. Madfa
- Department of Conservative Dentistry, Faculty of Dentistry, University of Thamar, Yemen
- Corresponding author at: Department of Conservative Dentistry, Faculty of Dentistry, University of Thamar, Dhamar, Yemen. Tel.: +967 6503255.
| | - Xiao-Guang Yue
- Department of Safety Science and Engineering, Wuhan University of Technology, China
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Karimi E, Khalil-Allafi J, Khalili V. Electrophoretic deposition of double-layer HA/Al composite coating on NiTi. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 58:882-90. [DOI: 10.1016/j.msec.2015.09.035] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/08/2015] [Accepted: 09/07/2015] [Indexed: 10/23/2022]
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Chai H, Kaizer M, Chughtai A, Tong H, Tanaka C, Zhang Y. On the interfacial fracture resistance of resin-bonded zirconia and glass-infiltrated graded zirconia. Dent Mater 2015; 31:1304-11. [PMID: 26365987 DOI: 10.1016/j.dental.2015.08.161] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
Abstract
OBJECTIVE A major limiting factor for the widespread use of zirconia in prosthetic dentistry is its poor resin-cement bonding capabilities. We show that this deficiency can be overcome by infiltrating the zirconia cementation surface with glass. Current methods for assessing the fracture resistance of resin-ceramic bonds are marred by uneven stress distribution at the interface, which may result in erroneous interfacial fracture resistance values. We have applied a wedge-loaded double-cantilever-beam testing approach to accurately measure the interfacial fracture resistance of adhesively bonded zirconia-based restorative materials. METHODS The interfacial fracture energy GC was determined for adhesively bonded zirconia, graded zirconia and feldspathic ceramic bars. The bonding surfaces were subjected to sandblasting or acid etching treatments. Baseline GC was measured for bonded specimens subjected to 7 days hydration at 37°C. Long-term GC was determined for specimens exposed to 20,000 thermal cycles between 5 and 55°C followed by 2-month aging at 37°C in water. The test data were interpreted with the aid of a 2D finite element fracture analysis. RESULTS The baseline and long-term GC for graded zirconia was 2-3 and 8 times greater than that for zirconia, respectively. More significantly, both the baseline and long-term GC of graded zirconia were similar to those for feldspathic ceramic. SIGNIFICANCE The interfacial fracture energy of feldspathic ceramic and graded zirconia was controlled by the fracture energy of the resin cement while that of zirconia by the interface. GC for the graded zirconia was as large as for feldspathic ceramic, making it an attractive material for use in dentistry.
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Affiliation(s)
- Herzl Chai
- Tel Aviv University, School of Mechanical Engineering, Faculty of Engineering, Tel Aviv, Israel
| | - Marina Kaizer
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY 10010, USA; Federal University of Pelotas, Graduate Program in Dentistry, Pelotas, Brazil
| | - Asima Chughtai
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY 10010, USA
| | - Hui Tong
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY 10010, USA; School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, PR China
| | - Carina Tanaka
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY 10010, USA; Department of Biomaterial and Oral Biology, School of Dentistry, University of São Paulo, São Paulo, Brazil
| | - Yu Zhang
- New York University College of Dentistry, Department of Biomaterials and Biomimetics, 433 First Avenue, Room 810, New York, NY 10010, USA.
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Mechanical and biological properties of the micro-/nano-grain functionally graded hydroxyapatite bioceramics for bone tissue engineering. J Mech Behav Biomed Mater 2015; 48:1-11. [DOI: 10.1016/j.jmbbm.2015.04.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 03/31/2015] [Accepted: 04/01/2015] [Indexed: 12/29/2022]
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Liu R, Sun T, Zhang Y, Zhang Y, Jiang D, Shao L. The effect of graded glass–zirconia structure on the bond between core and veneer in layered zirconia restorations. J Mech Behav Biomed Mater 2015; 46:197-204. [DOI: 10.1016/j.jmbbm.2015.02.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/11/2015] [Accepted: 02/19/2015] [Indexed: 11/15/2022]
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Srikanth R, Kosmac T, Della Bona A, Yin L, Zhang Y. Effects of cementation surface modifications on fracture resistance of zirconia. Dent Mater 2015; 31:435-42. [PMID: 25687628 DOI: 10.1016/j.dental.2015.01.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 11/15/2014] [Accepted: 01/20/2015] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To examine the effects of glass infiltration (GI) and alumina coating (AC) on the indentation flexural load and four-point bending strength of monolithic zirconia. METHODS Plate-shaped (12 mm × 12 mm × 1.0 mm or 1.5 or 2.0 mm) and bar-shaped (4 mm × 3 mm × 25 mm) monolithic zirconia specimens were fabricated. In addition to monolithic zirconia (group Z), zirconia monoliths were glass-infiltrated or alumina-coated on their tensile surfaces to form groups ZGI and ZAC, respectively. They were also glass-infiltrated on their upper surfaces, and glass-infiltrated or alumina-coated on their lower (tensile) surfaces to make groups ZGI2 and ZAC2, respectively. For comparison, porcelain-veneered zirconia (group PVZ) and monolithic lithium disilicate glass-ceramic (group LiDi) specimens were also fabricated. The plate-shaped specimens were cemented onto a restorative composite base for Hertzian indentation using a tungsten carbide spherical indenter with a radius of 3.2mm. Critical loads for indentation flexural fracture at the zirconia cementation surface were measured. Strengths of bar-shaped specimens were evaluated in four-point bending. RESULTS Glass infiltration on zirconia tensile surfaces increased indentation flexural loads by 32% in Hertzian contact and flexural strength by 24% in four-point bending. Alumina coating showed no significant effect on resistance to flexural damage of zirconia. Monolithic zirconia outperformed porcelain-veneered zirconia and monolithic lithium disilicate glass-ceramics in terms of both indentation flexural load and flexural strength. SIGNIFICANCE While both alumina coating and glass infiltration can be used to effectively modify the cementation surface of zirconia, glass infiltration can further increase the flexural fracture resistance of zirconia.
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Affiliation(s)
- Ramanathan Srikanth
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY 10010, USA
| | - Tomaz Kosmac
- Engineering Ceramics Department, Jozef Stefan Institute, Jamova 39, SI 1000 Ljubljana, Slovenia
| | - Alvaro Della Bona
- Post-graduation Program in Dentistry, Dental School, University of Passo Fundo, Passo Fundo, RS, Brazil
| | - Ling Yin
- School of Engineering and Physical Sciences, James Cook University, Townsville, Qld 4811, Australia
| | - Yu Zhang
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY 10010, USA.
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Bending strength of zirconia/porcelain functionally graded materials prepared using spark plasma sintering. J Dent 2014; 42:1569-76. [DOI: 10.1016/j.jdent.2014.09.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/19/2014] [Accepted: 09/22/2014] [Indexed: 11/24/2022] Open
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Comparison of various functionally graded femoral prostheses by finite element analysis. ScientificWorldJournal 2014; 2014:807621. [PMID: 25302331 PMCID: PMC4163328 DOI: 10.1155/2014/807621] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/22/2014] [Accepted: 06/22/2014] [Indexed: 11/18/2022] Open
Abstract
This study is focused on finite element analysis of a model comprising femur into which a femoral component of a total hip replacement was implanted. The considered prosthesis is fabricated from a functionally graded material (FGM) comprising a layer of a titanium alloy bonded to a layer of hydroxyapatite. The elastic modulus of the FGM was adjusted in the radial, longitudinal, and longitudinal-radial directions by altering the volume fraction gradient exponent. Four cases were studied, involving two different methods of anchoring the prosthesis to the spongy bone and two cases of applied loading. The results revealed that the FG prostheses provoked more SED to the bone. The FG prostheses carried less stress, while more stress was induced to the bone and cement. Meanwhile, less shear interface stress was stimulated to the prosthesis-bone interface in the noncemented FG prostheses. The cement-bone interface carried more stress compared to the prosthesis-cement interface. Stair climbing induced more harmful effects to the implanted femur components compared to the normal walking by causing more stress. Therefore, stress shielding, developed stresses, and interface stresses in the THR components could be adjusted through the controlling stiffness of the FG prosthesis by managing volume fraction gradient exponent.
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On the interfacial fracture of porcelain/zirconia and graded zirconia dental structures. Acta Biomater 2014; 10:3756-61. [PMID: 24769152 DOI: 10.1016/j.actbio.2014.04.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 04/10/2014] [Accepted: 04/16/2014] [Indexed: 11/23/2022]
Abstract
Porcelain fused to zirconia (PFZ) restorations are widely used in prosthetic dentistry. However, their susceptibility to fracture remains a practical problem. The failure of PFZ prostheses often involves crack initiation and growth in the porcelain, which may be followed by fracture along the porcelain/zirconia (P/Z) interface. In this work, we characterized the process of fracture in two PFZ systems, as well as a newly developed graded glass-zirconia structure with emphases placed on resistance to interfacial cracking. Thin porcelain layers were fused onto Y-TZP plates with or without the presence of a glass binder. The specimens were loaded in a four-point-bending fixture with the thin porcelain veneer in tension, simulating the lower portion of the connectors and marginal areas of a fixed dental prosthesis (FDP) during occlusal loading. The evolution of damage was observed by a video camera. The fracture was characterized by unstable growth of cracks perpendicular to the P/Z interface (channel cracks) in the porcelain layer, which was followed by stable cracking along the P/Z interface. The interfacial fracture energy GC was determined by a finite-element analysis taking into account stress-shielding effects due to the presence of adjacent channel cracks. The resulting GC was considerably less than commonly reported values for similar systems. Fracture in the graded Y-TZP samples occurred via a single channel crack at a much greater stress than for PFZ. No delamination between the residual glass layer and graded zirconia occurred in any of the tests. Combined with its enhanced resistance to edge chipping and good esthetic quality, graded Y-TZP emerges as a viable material concept for dental restorations.
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Ren L, Zhang Y. Sliding contact fracture of dental ceramics: Principles and validation. Acta Biomater 2014; 10:3243-53. [PMID: 24632538 DOI: 10.1016/j.actbio.2014.03.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 03/02/2014] [Accepted: 03/05/2014] [Indexed: 11/26/2022]
Abstract
Ceramic prostheses are subject to sliding contact under normal and tangential loads. Accurate prediction of the onset of fracture at two contacting surfaces holds the key to greater long-term performance of these prostheses. In this study, building on stress analysis of Hertzian contact and considering fracture criteria for linear elastic materials, a constitutive fracture mechanics relation was developed to incorporate the critical fracture load with the contact geometry, coefficient of friction and material fracture toughness. Critical loads necessary to cause fracture under a sliding indenter were calculated from the constitutive equation, and compared with the loads predicted from elastic stress analysis in conjunction with measured critical load for frictionless normal contact-a semi-empirical approach. The major predictions of the models were calibrated with experimentally determined critical loads of current and future dental ceramics after contact with a rigid spherical slider. Experimental results conform with the trends predicted by the models.
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Oshkour AA, Talebi H, Seyed Shirazi SF, Yau YH, Tarlochan F, Abu Osman NA. Effect of Geometrical Parameters on the Performance of Longitudinal Functionally Graded Femoral Prostheses. Artif Organs 2014; 39:156-64. [DOI: 10.1111/aor.12315] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Azim Ataollahi Oshkour
- Department of Mechanical Engineering; Faculty of Engineering; University of Malaya; Kuala Lumpur Malaysia
| | - Hossein Talebi
- Institute of Structural Mechanics; Bauhaus-Universitat Weimar; Weimar Germany
| | - Seyed Farid Seyed Shirazi
- Department of Mechanical Engineering; Faculty of Engineering; University of Malaya; Kuala Lumpur Malaysia
| | - Yat Huang Yau
- Department of Mechanical Engineering; Faculty of Engineering; University of Malaya; Kuala Lumpur Malaysia
| | - Faris Tarlochan
- Department of Mechanical and Industrial Engineering; College of Engineering; Qatar University; Doha Qatar
| | - Noor Azuan Abu Osman
- Department of Biomedical Engineering; Faculty of Engineering; University of Malaya; Kuala Lumpur Malaysia
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Oshkour AA, Abu Osman NA, Davoodi MM, Yau YH, Tarlochan F, Wan Abas WAB, Bayat M. Finite element analysis on longitudinal and radial functionally graded femoral prosthesis. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2013; 29:1412-1427. [PMID: 23922316 DOI: 10.1002/cnm.2583] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2012] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 06/02/2023]
Abstract
This study focused on developing a 3D finite element model of functionally graded femoral prostheses to decrease stress shielding and to improve total hip replacement performance. The mechanical properties of the modeled functionally graded femoral prostheses were adjusted in the sagittal and transverse planes by changing the volume fraction gradient exponent. Prostheses with material changes in the sagittal and transverse planes were considered longitudinal and radial prostheses, respectively. The effects of cemented and noncemented implantation methods were also considered in this study. Strain energy and von Mises stresses were determined at the femoral proximal metaphysis and interfaces of the implanted femur components, respectively. Results demonstrated that the strain energy increased proportionally with increasing volume fraction gradient exponent, whereas the interface stresses decreased on the prostheses surfaces. A limited increase was also observed at the surfaces of the bone and cement. The periprosthetic femur with a noncemented prosthesis exhibited higher strain energy than with a cemented prosthesis. Radial prostheses implantation displayed more strain energy than longitudinal prostheses implantation in the femoral proximal part. Functionally graded materials also increased strain energy and exhibited promising potentials as substitutes of conventional materials to decrease stress shielding and to enhance total hip replacement lifespan.
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Affiliation(s)
- Azim Ataollahi Oshkour
- Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia
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Abstract
OBJECTIVES Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics. DATA/SOURCES The nature of various fatigue modes is elucidated using fracture test data on ceramic layer specimens from the dental and biomechanics literature. CONCLUSIONS Failure modes can change over a lifetime, depending on restoration geometry, loading conditions and material properties. Modes that operate in single-cycle loading may be dominated by alternative modes in multi-cycle loading. While post-mortem examination of failed prostheses can determine the sources of certain fractures, the evolution of these fractures en route to failure remains poorly understood. Whereas it is commonly held that loss of load-bearing capacity of dental ceramics in repetitive loading is attributable to chemically assisted 'slow crack growth' in the presence of water, we demonstrate the existence of more deleterious fatigue mechanisms, mechanical rather than chemical in nature. Neglecting to account for mechanical fatigue can lead to gross overestimates in predicted survival rates. CLINICAL SIGNIFICANCE Strategies for prolonging the clinical lifetimes of ceramic restorations are proposed based on a crack-containment philosophy.
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Mehrali M, Shirazi FS, Mehrali M, Metselaar HSC, Kadri NAB, Osman NAA. Dental implants from functionally graded materials. J Biomed Mater Res A 2013; 101:3046-57. [PMID: 23754641 DOI: 10.1002/jbm.a.34588] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 01/04/2013] [Indexed: 11/05/2022]
Abstract
Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care.
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Affiliation(s)
- Mehdi Mehrali
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia
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Zhang Y. Overview: Damage resistance of graded ceramic restorative materials. JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 2012; 32:2623-2632. [PMID: 22778494 PMCID: PMC3390941 DOI: 10.1016/j.jeurceramsoc.2012.02.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Improving mechanical response of materials is of great interest in a wide range of disciplines, including biomechanics, tribology, geology, optoelectronics, and nanotechnology. It has been long recognized that spatial gradients in surface composition and structure can improve the mechanical integrity of a material. This review surveys recent results of sliding-contact, flexural, and fatigue tests on graded ceramic materials from our laboratories and elsewhere. Although our findings are examined in the context of possible applications for next-generation, graded all-ceramic dental restorations, implications of our studies have broad impact on biomedical, civil, structural, and an array of other engineering applications.
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Affiliation(s)
- Yu Zhang
- 345 East 24th Street, Room 813C, New York, NY 10010, USA, Tel.: +1 212 998 9637; Fax: +1 212 995 4244.
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