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PEKKAN G, PEKKAN K, BAYINDIR BÇ, ÖZCAN M, KARASU B. Factors affecting the translucency of monolithic zirconia ceramics: A review from materials science perspective. Dent Mater J 2020; 39:1-8. [DOI: 10.4012/dmj.2019-098] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Gürel PEKKAN
- Department of Prosthodontics, Faculty of Dentistry, Tekirdag Namik Kemal University
| | - Keriman PEKKAN
- Department of Ceramics and Glass, Faculty of Fine Arts, Kutahya Dumlupinar University
| | | | - Mutlu ÖZCAN
- Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Center for Dental and Oral Medicine, Dental Materials Unit, University of Zürich
| | - Bekir KARASU
- Department of Metallurgical and Materials Engineering, Faculty of Engineering, Eskisehir Technical University
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202
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The effect of restoration thickness and resin cement shade on the color and translucency of a high-translucency monolithic zirconia. J Prosthet Dent 2020; 123:149-154. [DOI: 10.1016/j.prosdent.2018.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 11/08/2018] [Accepted: 11/08/2018] [Indexed: 11/18/2022]
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203
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Findakly MB, Jasim HH. Influence of preparation design on fracture resistance of different monolithic zirconia crowns: A comparative study. J Adv Prosthodont 2019; 11:324-330. [PMID: 31897271 PMCID: PMC6933051 DOI: 10.4047/jap.2019.11.6.324] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/08/2019] [Accepted: 12/11/2019] [Indexed: 12/18/2022] Open
Abstract
PURPOSE The aim of the study was to evaluate and compare the fracture resistance and modes of fracture of monolithic zirconia crowns with two preparation designs. MATERIALS AND METHODS Forty human maxillary first premolar teeth were extracted for orthodontic purposes and divided into two main groups (n=20): Group A: monolithic traditional zirconia; Group B: monolithic translucent zirconia. The groups were further subdivided into two subgroups (n=10): (A1, B1) shoulder margin design; (A2, B2) feather-edge margin design. Teeth were prepared with either a 1 mm shoulder margin design or a feather-edge margin design. The prepared teeth were scanned using a digital intraoral scanner. The crowns were cemented using self-adhesive resin cement. All cemented teeth were stored in water for 7 days and thermocycling was done before testing. All samples were subjected to compressive axial loading until fracture. The fractographic analysis was done to assess the modes of fracture of the tested samples. RESULTS The highest mean values of fracture resistance were recorded in kilo-newton and were in the order of subgroup A1 (2.903); subgroup A2 (2.3); subgroup B1 (1.854) and subgroup B2 (1.523). One-way ANOVA showed a statistically significant difference among the 4 subgroups. Concerning modes of fracture, the majority of samples in subgroups A1 and B1 were fracture of restoration and/or tooth, while in subgroups A2 and B2, the majority of samples fractured through the central fossa. CONCLUSION Even though all the tested crowns fractured at a higher level than the maximum occlusal forces, the shoulder margin design was better than the feather-edge margin design and the monolithic traditional zirconia was better than the monolithic translucent zirconia in terms of fracture strength.
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Affiliation(s)
- Meelad Basil Findakly
- Department of Conservative Dentistry, College of Dentistry, Mustansiriyah University, Baghdad, Iraq
| | - Haider Hasan Jasim
- Department of Conservative Dentistry, College of Dentistry, Mustansiriyah University, Baghdad, Iraq
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204
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Kurt M, Turhan Bal B. Effects of accelerated artificial aging on the translucency and color stability of monolithic ceramics with different surface treatments. J Prosthet Dent 2019; 121:712.e1-712.e8. [PMID: 30929661 DOI: 10.1016/j.prosdent.2019.01.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 01/14/2019] [Accepted: 01/14/2019] [Indexed: 11/30/2022]
Abstract
STATEMENT OF PROBLEM Different surface finishing procedures can be applied to monolithic restorations. However, information is limited regarding the long-term performance of these procedures. PURPOSE The purpose of this in vitro study was to evaluate the effect of aging on the translucency and color stability of monolithic ceramics with different surface finishing procedures. MATERIAL AND METHODS Disk-shaped (14×1.5 mm) specimens of monolithic zirconia (Zirkonzahn Prettau [ZZ]) and lithium disilicate glass-ceramic (IPS e.max Press [IPS]) were fabricated. The specimens were divided into 3 subgroups according to the surface treatments (n=9, G: glazing, R: rubber polishing system, and P: rubber polishing system followed by polishing paste). Color measurements were made by using a spectrophotometer before and after an ultraviolet aging process. L*, a*, and b* parameters were recorded. ΔE and translucency parameter (TP) values were calculated. One specimen from each subgroup was examined by scanning electron microscopy (×30 000). The data were statistically analyzed using the Mann-Whitney U, Kruskal-Wallis, and post hoc tests (α=.05). RESULTS ΔE values of group ZZ (5.03) exceeded the clinically acceptable level (3.5); however, the color change was not clinically perceptible for IPS (0.41). The ΔE value of the subgroup P was found to be higher than that of the others for ZZ (P<.001). The ΔE value was not affected by the surface treatment for IPS. Group IPS showed significantly higher translucency than the ZZ group (P<.001). TP values were not affected by the surface treatment in either material and decreased after aging. However, changes in the TP values were too slight to be clinically perceptible. CONCLUSIONS Lithium disilicate ceramic was found to be more esthetic than monolithic zirconia ceramic in terms of color stability and translucency.
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Affiliation(s)
- Meral Kurt
- Research Assistant, Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey.
| | - Bilge Turhan Bal
- Professor, Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara, Turkey
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205
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High-translucent yttria-stabilized zirconia ceramics are wear-resistant and antagonist-friendly. Dent Mater 2019; 35:1776-1790. [PMID: 31727445 DOI: 10.1016/j.dental.2019.10.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/04/2019] [Accepted: 10/14/2019] [Indexed: 12/13/2022]
Abstract
OBJECTIVES To evaluate two-body wear of three zirconia ceramics stabilized with 3, 4 and 5mol% yttria and to compare their wear behavior with that of a lithium-disilicate glass-ceramic. METHODS Sixteen rectangular-shaped specimens made from three grades of zirconia ceramics and a lithium-disilicate glass-ceramic were polished and dynamically loaded in a chewing simulator (2kg vertical load, 2.1Hz) under water at 90°C for 1.2×106 cycles (about 7 days) in the ball-on-plate mode against steatite antagonists. Surface roughness was measured before and after wear testing. Wear tracks were scanned with a non-contact 3D profilometer and super-impositions were used to determine wear loss of the antagonists. Wear surfaces were imaged by SEM. XRD and micro-Raman spectroscopy were used to characterize phase transformation and stress status in the worn and unworn areas of the zirconia ceramics. RESULTS Independent of fracture toughness, strength and aging-susceptibility, the three zirconia ceramics showed a similar and limited amount of wear (∼10μm in depth) and were more wear-resistant than the lithium-disilicate glass-ceramic (∼880μm in depth). Abrasive wear without obvious cracks was observed for all investigated zirconias, whereas the glass-ceramic with a lower fatigue threshold and high susceptibility to surface dissolution exhibited significant abrasion, fatigue and corrosion wear. All three zirconia ceramics yielded a lower antagonist wear than the glass-ceramic and no significant differences were found between the zirconia ceramics. SIGNIFICANCE In the context of this study, high-translucent zirconia ceramics stabilized with a higher yttria content, recently introduced in the dental field, were as wear-resistant and antagonist-friendly as conventional high-strength zirconia and suitable for monolithic restorations.
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206
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Kaizer MR, Kolakarnprasert N, Rodrigues C, Chai H, Zhang Y. Probing the interfacial strength of novel multi-layer zirconias. Dent Mater 2019; 36:60-67. [PMID: 31727444 DOI: 10.1016/j.dental.2019.10.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 09/07/2019] [Accepted: 10/16/2019] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The rapidly increasing use of zirconia-based CAD/CAM multi-layer structures in dentistry calls for a thorough evaluation of their mechanical integrity. This work examines the effect of the multi-layering architecture as well as variations in composition and inclusion of pigments among the layers on the flexural strength of multi-layer zirconias. METHODS A modified 4-point bending test, aided by a Finite Element Analysis (FEA), was used to probe the interfacial strength of 3 classes of yttria-partially-stabilized zirconia: Ultra Translucent Multi-Layer (UTML-5Y-PSZ), Super Translucent Multi-Layer (STML-4Y-PSZ), Multi-Layer (ML-3Y-PSZ). In accord with the size limitation (22-mm height) of CAD/CAM pucks, test samples were prepared in the form of "long" (25×2×3mm) and "short" (17.8×1.5×2mm) beams. Homogeneous beams (both long and short) were produced from either the Enamel (the lightest shade) or Dentin (the darkest shade) layer, whereas multi-layer beams (short beam only) were obtained by cutting the pucks along their thickness direction, where the material components of various shades were stacked. RESULTS The Enamel and Dentin layers exhibited similar flexural strength for a given material class, with ML amassing the highest strength (800-900MPa) followed by STML (560-650MPa) and UTML (470-500MPa). The 3 classes of multi-layer zirconia showed a trade-off between strength and translucency, reflecting different yttria contents in these materials. The failure stress of the cross-sectional multi-layer beams was, however, ∼30% lower than that of their Enamel or Dentin layer counterparts, regardless of material tested. SIGNIFICANCE The weakness of interfaces is a drawback in these materials. Additionally, when measuring strength using short beam flexure, friction between the specimen and supporting pins and accuracy in determining loading span distances may lead to major errors.
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Affiliation(s)
- Marina R Kaizer
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA; Graduate Program in Dentistry, Positivo University, Curitiba, PR, Brazil
| | - Nantawan Kolakarnprasert
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA
| | - Camila Rodrigues
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA; Post-Graduation Program in Dental Sciences, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - Herzl Chai
- Tel Aviv University, School of Mechanical Engineering, Faculty of Engineering, Tel Aviv, Israel
| | - Yu Zhang
- Department of Biomaterials and Biomimetics, New York University College of Dentistry, New York, NY, USA.
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207
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Koenig V, Wulfman C, Bekaert S, Dupont N, Le Goff S, Eldafrawy M, Vanheusden A, Mainjot A. Clinical behavior of second-generation zirconia monolithic posterior restorations: Two-year results of a prospective study with Ex vivo analyses including patients with clinical signs of bruxism. J Dent 2019; 91:103229. [PMID: 31722238 DOI: 10.1016/j.jdent.2019.103229] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 11/04/2019] [Accepted: 11/05/2019] [Indexed: 12/17/2022] Open
Abstract
OBJECTIVES This study aimed to investigate (1) clinical outcomes of second-generation zirconia restorations, including patients with bruxism clinical signs, and (2) the material wear process. METHODS A total of 95 posterior monolithic zirconia tooth-elements in 45 patients were evaluated, 85 on implants and 10 on natural teeth, and 20.3% of restorations being fixed partial dentures (FPDs). Occlusal contact point areas were determined and half of those areas were left unglazed and just polished. Restorations were clinically evaluated following criteria of the World Dental Federation and antagonistic teeth were examined at each evaluation time. Wear ex vivo analyses using SEM and 3D laser profilometry were performed at baseline and after 6 months, 1 year, and 2 years respectively, temporarily removing the prostheses. RESULTS The Kaplan-Meier survival rate of restorations was 93.3% (100% for FPDs) and the success rate was 81.8%, with 4 abutment debondings, 3 tooth-supported crown debondings (provisional cement use), 1 restoration fracture, 1 minor chipping, 1 core fracture, 1 root fracture, and 2 implant losses. 80% of catastrophic failures occurred in patients with clinical signs of bruxism (61.7% of patients). Complications were also observed on antagonistic teeth (3 catastrophic failures). Clinical evaluation of the restorations showed good results from the aesthetic, functional, and biological perspective. Zirconia wear was inferior to 15 μm, while glaze wear was observed on all occlusal contact areas after 1 year. CONCLUSIONS Monolithic zirconia FPDs are promising but the failure rate of single-unit restorations was not as high as expected in this sample including patients with bruxism clinical signs. CLINICAL SIGNIFICANCE Within study limitations, FPDs showed excellent short-term results but further research is needed for single-unit restorations considering samples, which do not exclude bruxers. The weak link is the restoration support or the antagonist tooth, one hypothesis being that zirconia stiffness and lack of resilience do not promote occlusal stress damping.
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Affiliation(s)
- V Koenig
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Department of Fixed Prosthodontics, Institute of Dentistry, University of Liège Hospital (CHU), 45 Quai G. Kurth, Liège, 4020, Belgium
| | - C Wulfman
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Unité de Recherches en Biomatériaux Innovants et Interfaces (URB2i) - EA4462, Faculté de Chirurgie Dentaire, Université Paris Descartes, Sorbonne Paris-Cité, Montrouge, 92120, France
| | - S Bekaert
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Department of Fixed Prosthodontics, Institute of Dentistry, University of Liège Hospital (CHU), 45 Quai G. Kurth, Liège, 4020, Belgium
| | - N Dupont
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Department of Fixed Prosthodontics, Institute of Dentistry, University of Liège Hospital (CHU), 45 Quai G. Kurth, Liège, 4020, Belgium
| | - S Le Goff
- Unité de Recherches en Biomatériaux Innovants et Interfaces (URB2i) - EA4462, Faculté de Chirurgie Dentaire, Université Paris Descartes, Sorbonne Paris-Cité, Montrouge, 92120, France
| | - M Eldafrawy
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium
| | - A Vanheusden
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Department of Fixed Prosthodontics, Institute of Dentistry, University of Liège Hospital (CHU), 45 Quai G. Kurth, Liège, 4020, Belgium
| | - A Mainjot
- Dental Biomaterials Research Unit (d-BRU), University of Liège (ULiège), 45 Quai G. Kurth, Liège, 4020, Belgium; Department of Fixed Prosthodontics, Institute of Dentistry, University of Liège Hospital (CHU), 45 Quai G. Kurth, Liège, 4020, Belgium.
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208
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Kou W, Garbrielsson K, Borhani A, Carlborg M, Molin Thorén M. The effects of artificial aging on high translucent zirconia. Biomater Investig Dent 2019; 6:54-60. [PMID: 31998872 PMCID: PMC6964773 DOI: 10.1080/26415275.2019.1684201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 10/14/2019] [Indexed: 11/17/2022] Open
Abstract
Zirconia is known for its high strength but lacking translucency. Recently, a new type of high translucent zirconia, 5 mol% yttria partially stabilized zirconia (5Y-PSZ), with a larger fraction of cubic zirconia phase has become commercially available. However, the resistance to aging of these commercially available zirconia materials is not yet fully established. Purpose: The aim of the present study was to analyze the effects of artificial aging on surface roughness, transparency, phase transformation and biaxial flexural strength of two 5Y-PSZ products, DD cubeX2 and Prettau Anterior. Materials and methods: The artificial aging was performed in an autoclave under 2 bars of pressure at 134 °C for 10 hours, which is estimated to correspond to 30–40 years in vivo. Artificial aging for 10 hours had no significant effect on surface roughness, transparency, or phase transformation for either of the tested materials. Results: DD cubeX2 had higher mean flexural strength than Prettau Anterior both before and after artificial aging for 10 hours (p < .05). DD cubeX2 showed, however, a significant reduction in flexural strength after artificial aging (p < .05), whereas Prettau Anterior showed a slight increase in flexural strength after artificial aging but not at a significant level. Conclusion: Within the limitation of the present study, both DD cubeX2 and Prettau Anterior seems to be relatively resistant to aging. However, a wider range of measured flexural strength indicated that Prettau Anterior probably is a less stable material than DD cubeX2, which also means that the flexural strength of DD cubeX2 could be more predictable.
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Affiliation(s)
- Wen Kou
- Department of Odontology, Umeå University, Umeå, Sweden
| | | | | | - Markus Carlborg
- Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden
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209
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Bittar BF, Miranda JS, Simões AC, de Carvalho Ramos N, Machado JPB, Zhang Y, Souza ROA, Leite FPP. Effect of extrinsic pigmentation and surface treatments on biaxial flexure strength after cyclic loading of a translucent ZrO 2 ceramic. Dent Mater 2019; 35:1644-1653. [PMID: 31575489 PMCID: PMC6858620 DOI: 10.1016/j.dental.2019.08.117] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 08/12/2019] [Accepted: 08/31/2019] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the influence of extrinsic pigmentation on the biaxial flexural strength and surface topographic of translucent Y-TZP (InCoris TZI - Sirona - USA) subjected to several surface treatments. METHODS Sintered zirconia discs-shaped specimens (n=120) (ø:12mm; thickness:1.2mm; ISO 6872) were prepared and divided (n=15) according to various factors: "extrinsic pigmentation" (n: without; p: with) and "surface treatments" (C: control - as sintered; A: abraded with silica-coated alumina particles (30μm); G: glazed with a thin film of low-fusing porcelain glaze; GH: glazed and etched with 10% hydrofluoridric acid for 60s. Mechanical cycling (1.2×106 cycles, 200N, 3.8Hz) and flexural strength test (1mm/min - 1000kg cell) were performed. Two-way ANOVA and Tukey's were used for statistical test (α=0.05). Weibull analysis was used to evaluate the strength reliability. Samples were analyzed via (1) an optical profilometer to determine the surface roughness (Ra); (2) an X-ray diffraction (XRD) to evaluate phase transformations; and (3) a SEM equipped with an energy dispersive X-ray spectroscopy (EDX) to elucidate morphological properties and chemical compositions. RESULTS Regardless of the surface treatment (p=0.5459) (Cn: 560.16MPa; Gn: 573.36MPa; An: 643.51MPa; GHn: 542.94MPa; Cp: 628.04MPa; Gp: 641.90MPa; Ap: 554.47MPa; GHp :602.84MPa) and extrinsic pigmentation (p=0.1280) there was no difference in the flexural strength among the experimental groups. According to the XRD analysis, phase transformations occurred in the An group (t→m) and in Ap group (t→c). Surface roughness was affected by surface treatments (An - p=0.001) and extrinsic pigmentation (Gp - p=0.001). SIGNIFICANCE The biaxial flexural strength of the tested samples was not affected neither by surface treatments nor by pigmentation, although it can cause phase transformation and promote surface roughness.
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Affiliation(s)
- Breno Fortes Bittar
- Department of Restorative Dentistry, Federal University of Juiz de Fora (UFJF), Juiz de Fora/MG, Brazil
| | - Jean Soares Miranda
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University - UNESP, São José dos Campos, São Paulo, Brazil
| | - Arthur Chaves Simões
- Department of Restorative Dentistry, Federal University of Juiz de Fora (UFJF), Juiz de Fora/MG, Brazil
| | - Nathália de Carvalho Ramos
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University - UNESP, São José dos Campos, São Paulo, Brazil
| | - João P B Machado
- Federal University of Rio Grande do Norte/UFRN, Health Science Center, Department of Dentistry, Natal-RN/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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Abstract
This article describes and illustrates the current state of chairside computer-aided design computer-aided manufacturing technologies and materials. It provides a historical background and discusses the different components of the chairside digital workflow: intraoral scanners, design software, milling machines, and sinter furnaces. The material range available for chairside digital dentistry is broad and includes polymethyl methacrylates, composite resins, and a large variety of ceramics. Clinical applications and success rates of the different material groups are summarized and discussed based on the current scientific evidence.
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Affiliation(s)
- Markus B Blatz
- Department of Preventive and Restorative Sciences, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104, USA.
| | - Julian Conejo
- Department of Preventive and Restorative Sciences, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104, USA
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211
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Blatz M, Chiche G, Bahat O, Roblee R, Coachman C, Heymann H. Evolution of Aesthetic Dentistry. J Dent Res 2019; 98:1294-1304. [DOI: 10.1177/0022034519875450] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
One of the main goals of dental treatment is to mimic teeth and design smiles in a most natural and aesthetic manner, based on the individual and specific needs of the patient. Possibilities to reach that goal have significantly improved over the last decade through new and specific treatment modalities, steadily enhanced and more aesthetic dental materials, and novel techniques and technologies. This article gives an overview of the evolution of aesthetic dentistry over the past 100 y from a historical point of view and highlights advances in the development of dental research and clinical interventions that have contributed the science and art of aesthetic dentistry. Among the most noteworthy advancements over the past decade are the establishment of universal aesthetic rules and guidelines based on the assessment of natural aesthetic parameters, anatomy, and physiognomy; the development of tooth whitening and advanced restorative as well as prosthetic materials and techniques, supported by the pioneering discovery of dental adhesion; the significant progress in orthodontics and periodontal as well as oral and maxillofacial surgery; and, most recently, the implementation of digital technologies in the 3-dimensional planning and realization of truly natural, individual, and aesthetic smiles. In the future, artificial intelligence and machine learning will likely lead to automation of aesthetic evaluation, smile design, and treatment-planning processes.
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Affiliation(s)
- M.B. Blatz
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - G. Chiche
- Department of Restorative Sciences, Dental College of Georgia, Augusta University, Augusta, GA, USA
| | - O. Bahat
- Private Practice, Beverly Hills, CA, USA
| | - R. Roblee
- Private Practice Limited to Orthodontics, Fayetteville, AR, USA
| | - C. Coachman
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Private Practice, Sao Paulo, Brazil
| | - H.O. Heymann
- Division of Operative Dentistry, School of Dentistry, University of North Carolina, Chapel Hill, NC, USA
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212
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Auzani ML, Dapieve KS, Zucuni CP, Rocha Pereira GK, Valandro LF. Influence of shading technique on mechanical fatigue performance and optical properties of a 4Y-TZP ceramic for monolithic restorations. J Mech Behav Biomed Mater 2019; 102:103457. [PMID: 31605929 DOI: 10.1016/j.jmbbm.2019.103457] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/26/2019] [Accepted: 09/28/2019] [Indexed: 10/25/2022]
Abstract
This study aimed to evaluate the effect of shading procedures on the fatigue performance and optical properties of an yttria-stabilized tetragonal zirconia polycrystal ceramic (4Y-TZP - stabilized by 4 mol% Y2O3). Disc-shaped specimens were produced at pre-sintered stage and randomly allocated into 5 groups (n=15) considering the shading technique: Ctrl (no pigmentation); Brush 1× and Brush 3× (brushing on 1 or 3 applications, respectively); Immer 2min and Immer 4min (immersion for 2 or 4 min, respectively). Following each pigment application, the specimens were dried in accordance with the manufacturers' guidelines (15 min in a stove at 70 °C) and sintered in a specific furnace. Biaxial flexural fatigue test followed a step-stress approach (initial strength: 200 MPa; step-size: 25 MPa; 10.000 cycles/step; frequency: 20 Hz). Optical measurements were conducted in a spectrophotometer following the CIEDE2000 parameters. Roughness, topography, crystalline grain size, crystalline phase content and fractography analysis were also performed. The flexural fatigue strength (FFS) and the number of cycles to fracture (CFF) were statistically affected by pigmentation techniques (mean FFS in MPa/mean CFF): Ctrl (446.7/105,619) > Brush 1 × (436.7/102,854) ≥ Brush 3 × (405.0/89,962) ≥ Immer 2 min (395.0/85,103) ≥ Immer 4 min (383.3/81,382), although the exposure intensity (increase in number of applications or in application time) to the pigment had no effect (Brush 1 × = Brush 3 × ; Immer 2 min = Immer 4 min). Regarding optical properties, shading techniques similarly affected translucency and opalescence parameters, regardless of the exposure intensity to the pigment (Brush 1 × = Brush 3 × = Immer 2 min = Immer 4 min > Ctrl), whereas the exposure intensity to the pigment only promoted relevant alterations in the color change parameter (ΔE00) for the brushing technique (Brush 3 × > Brush 1 × ). No difference was observed in crystalline phase content, topographic pattern or roughness, although an increase in the zirconia grain size could be detected. Thus, the shading technique might affect the fatigue behavior and promote optical changes in a 4Y-TZP ceramic.
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Affiliation(s)
- Maria Luiza Auzani
- MSciD and PhD Graduate Programs in Oral Science - Prosthodontic Units, Faculty of Odontology, Federal University of Santa Maria - UFSM, Santa Maria, Rio Grande do Sul, Brazil.
| | - Kiara Serafini Dapieve
- MSciD and PhD Graduate Programs in Oral Science - Prosthodontic Units, Faculty of Odontology, Federal University of Santa Maria - UFSM, Santa Maria, Rio Grande do Sul, Brazil.
| | - Camila Pauleski Zucuni
- MSciD and PhD Graduate Programs in Oral Science - Prosthodontic Units, Faculty of Odontology, Federal University of Santa Maria - UFSM, Santa Maria, Rio Grande do Sul, Brazil.
| | - Gabriel Kalil Rocha Pereira
- MSciD and PhD Graduate Programs in Oral Science - Prosthodontic Units, Faculty of Odontology, Federal University of Santa Maria - UFSM, Santa Maria, Rio Grande do Sul, Brazil.
| | - Luiz Felipe Valandro
- MSciD and PhD Graduate Programs in Oral Science - Prosthodontic Units, Faculty of Odontology, Federal University of Santa Maria - UFSM, Santa Maria, Rio Grande do Sul, Brazil.
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213
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Jansen JU, Lümkemann N, Letz I, Pfefferle R, Sener B, Stawarczyk B. Impact of high-speed sintering on translucency, phase content, grain sizes, and flexural strength of 3Y-TZP and 4Y-TZP zirconia materials. J Prosthet Dent 2019; 122:396-403. [DOI: 10.1016/j.prosdent.2019.02.005] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 02/19/2019] [Accepted: 02/19/2019] [Indexed: 01/24/2023]
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214
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JANSEN JU, LÜMKEMANN N, SENER B, STAWARCZYK B. Comparison of fracture toughness measurements for zirconia materials using two test methods. Dent Mater J 2019; 38:806-812. [DOI: 10.4012/dmj.2018-361] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Jan Ulrich JANSEN
- Department of Prosthetic Dentistry, Dental Material Unit, Ludwig-Maximilians-University Munich
| | - Nina LÜMKEMANN
- Department of Prosthetic Dentistry, Dental Material Unit, Ludwig-Maximilians-University Munich
| | - Beatrice SENER
- Periodontics and Cardiology, Clinic for Preventive Dentistry, University of Zurich
| | - Bogna STAWARCZYK
- Department of Prosthetic Dentistry, Dental Material Unit, Ludwig-Maximilians-University Munich
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215
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Lawson NC, Maharishi A. Strength and translucency of zirconia after high-speed sintering. J ESTHET RESTOR DENT 2019; 32:219-225. [PMID: 31515932 DOI: 10.1111/jerd.12524] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/25/2019] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To compare the strength and translucency of CAD/CAM zirconia blocks, with traditional and high-speed sintering, to lithium disilicate. MATERIALS AND METHODS Three zirconia materials (Katana STML Block, Prettau Anterior, and Zpex Smile) were tested with either traditional (7 hours) or high-speed (18 or 30 minutes in a SpeedFire furnace) sintering. A lithium disilicate material (IPS e.max CAD) was tested as a reference. Three-point bend flexural strength specimens (16 mm × 4 mm × 1.2 mm, n = 10) were tested on 14-mm-separated supports and loaded to failure at 1 mm/min. Specimens (1 mm thick, n = 10) were measured in a Color-i7 spectrophotometer against a black and white background to calculate translucency parameter. Zirconia specimens were thermally etched and a grain structure was observed with scanning electron microscopy. Data were analyzed with 1-way ANOVA and Tukey's post hoc analysis (α = 0.05). RESULTS There were significant differences between materials for flexural strength, translucency parameter, and grain size (P < .001). Grains became significantly larger and pores were present when two of the zirconia materials (Prettau Anterior and Zpex Smile) were sintered with a high-speed sintering program. CONCLUSIONS Two of the zirconia materials (Prettau Anterior and Zpex Smile) became less translucent and less strong using a high-speed sintering program, whereas another (Katana STML Block) was unaffected.
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Affiliation(s)
- Nathaniel C Lawson
- Division of Biomaterials, University of Alabama at Birmingham, Birmingham, Alabama
| | - Anvita Maharishi
- Division of Biomaterials, University of Alabama at Birmingham, Birmingham, Alabama
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216
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Yu NK, Park MG. Effect of different coloring liquids on the flexural strength of multilayered zirconia. J Adv Prosthodont 2019; 11:209-214. [PMID: 31497268 PMCID: PMC6718843 DOI: 10.4047/jap.2019.11.4.209] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/13/2019] [Accepted: 08/14/2019] [Indexed: 11/15/2022] Open
Abstract
PURPOSE The purpose of this study was to evaluate the effect of two coloring liquids (aqueous and acid-based coloring liquids) and the position of multilayered zirconia on the flexural strength of multilayered zirconia. MATERIALS AND METHODS The multilayered zirconia specimens were divided into upper and lower positions. The specimens were divided into three subgroups (n=10): non-shaded, acid-based coloring liquid, and aqueous coloring liquid. The specimens were cut using a milling machine and were immersed in either a acid-based coloring liquid or aqueous coloring liquid 2 times for 5 seconds. The specimens were sintered in a sintering furnace according to the manufacturer's introduction. The flexural strength of the specimen was measured using a universal testing machine and the surface of the specimen was observed using a field emission scanning electron microscope. RESULTS The flexural strength of multilayered zirconia was 400 – 500 MPa. There was no statistically significant difference among all groups (P>.05).The flexural strength of the multilayered zirconia was not influenced by the kind of coloring liquid used (P>.05). The flexural strength of the multilayered zirconia colored with the coloring liquids was not influenced by its position (P>.05). CONCLUSION The different coloring liquid application did not affect the flexural strength of multilayered zirconia of all positions.
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Affiliation(s)
- Na-Kyoung Yu
- Department of Dental Laboratory Science, College of Health Sciences, Catholic University of Pusan, Busan, Republic of Korea
| | - Mi-Gyoung Park
- Department of Dental Laboratory Science, College of Health Sciences, Catholic University of Pusan, Busan, Republic of Korea
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217
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Kontonasaki E, Rigos AE, Ilia C, Istantsos T. Monolithic Zirconia: An Update to Current Knowledge. Optical Properties, Wear, and Clinical Performance. Dent J (Basel) 2019; 7:dj7030090. [PMID: 31480688 PMCID: PMC6784470 DOI: 10.3390/dj7030090] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 07/22/2019] [Accepted: 08/20/2019] [Indexed: 01/09/2023] Open
Abstract
The purpose of this paper was to update the knowledge concerning the wear, translucency, as well as clinical performance of monolithic zirconia ceramics, aiming at highlighting their advantages and weaknesses through data presented in recent literature. New ultra-translucent and multicolor monolithic zirconia ceramics present considerably improved aesthetics and translucency, which, according to the literature reviewed, is similar to those of the more translucent lithium disilicate ceramics. A profound advantage is their high strength at thin geometries preserving their mechanical integrity. Based on the reviewed articles, monolithic zirconia ceramics cause minimal wear of antagonists, especially if appropriately polished, although no evidence still exists regarding the ultra-translucent compositions. Concerning the survival of monolithic zirconia restorations, the present review demonstrates the findings of the existing short-term studies, which reveal promising results after evaluating their performance for up to 5 or 7 years. Although a significant increase in translucency has been achieved, new translucent monolithic zirconia ceramics have to be further evaluated both in vitro and in vivo for their long-term potential to preserve their outstanding properties. Due to limited studies evaluating the wear properties of ultra-translucent material, no sound conclusions can be made, whereas well-designed clinical studies are urgently needed to enlighten issues of prognosis and long-term survival.
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Affiliation(s)
- Eleana Kontonasaki
- Department of Prosthodontics, School of Dentistry, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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218
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Alshamrani AA, De Souza GM. Effect of ionizing radiation on mechanical properties and translucency of monolithic zirconia. J Biomed Mater Res B Appl Biomater 2019; 108:1068-1076. [PMID: 31410974 DOI: 10.1002/jbm.b.34458] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/11/2019] [Accepted: 07/17/2019] [Indexed: 01/07/2023]
Abstract
This study aimed to evaluate the effect of radiation therapy (RT) on mechanical properties and translucency of monolithic zirconia. Yttria- stabilized zirconia (Y-PSZ) materials (14 × 4.0 × 1.5 mm) were divided in four experimental groups (n = 30): High-translucency/control (HT/C), high-translucency/irradiated (HT/I), low-translucency/control (LT/C), low-translucency/irradiated (LT/I). Irradiated specimens were submitted to a single dose irradiation of 70 Gray. Flexural strength (n = 10) (FS-3-point bending test), fatigue limits (n = 15) at 100,000 cycles (FLs-staircase approach), and translucency (n = 5) (TP-dental spectrometer) were analyzed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the materials. FS and TP data were analyzed by one-way Analysis of Variance (ANOVA) and Tukey HSD. FLs were analyzed using Dixon and Mood method, and Kaplan-Meier survival analysis. RT affected FS of LT zirconia (p = .032) but not of HT zirconia (p = .86). FLs and TP of both materials were not affected by RT (p > .05). Higher cubic content after RT was observed. In conclusion, RT may affect flexural strength and crystalline content of zirconia-based materials, but this effect was not observed under fatigue. Translucency of Y-PSZ restorations is also not affected by RT.
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Affiliation(s)
- Abdullah A Alshamrani
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada.,Department of Dental Health, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Grace M De Souza
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
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219
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Modeling of the Influence of Chemical Composition, Sintering Temperature, Density, and Thickness in the Light Transmittance of Four Zirconia Dental Prostheses. MATERIALS 2019; 12:ma12162529. [PMID: 31398941 PMCID: PMC6720388 DOI: 10.3390/ma12162529] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 07/31/2019] [Accepted: 08/06/2019] [Indexed: 11/25/2022]
Abstract
Research has increasingly been conducted to improve the toughness and aesthetics of zirconium oxide (zirconia) used in prosthetic dentistry. However, the balance between better mechanical properties and greater translucency, to ensure aesthetic requirements, is still a challenge in the development of a novel zirconia for dentistry applications. This study evaluated the transmittance of visible light for four types of pre-sintered zirconia blocks used in dentistry (3Y-SBE, Zpex, Zpex-4, and Zpex-Smile). The objective is to analyze the simultaneous influence of sintering temperature, in the range of 1450–1560 °C, as well as the chemical composition (%Y2O3), density, and thickness (1.0, 1.3, 1.6, and 2.0 mm) in the zirconia’s transmittance. To evaluate the interactive influence of these variables, a statistical learning model based on gradient boosting is applied. The results showed that the effect of the sintering temperature has an optimal (maximum transmittance) point. Increasing the temperature beyond this point reduces the transmittance of the material for all types of zirconia. Moreover, the optimal transmittance point is affected by the chemical composition of each type of zirconia. In addition, the results showed that the transmittance of all types of zirconia had an inverse relationship with the density, zirconia Zpex-Smile being the most sensitive to this parameter. Furthermore, the transmittance of 3Y-SBE, Zpex, and Zpex-4 decreases approximately linearly with the specimen thickness, whereas zirconia Zpex-Smile has a sublinear decrease, which is expected due to the optical isotropy of the cubic phase.
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220
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Sen N, Isler S. Microstructural, physical, and optical characterization of high-translucency zirconia ceramics. J Prosthet Dent 2019; 123:761-768. [PMID: 31383525 DOI: 10.1016/j.prosdent.2019.05.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 04/03/2019] [Accepted: 05/02/2019] [Indexed: 11/19/2022]
Abstract
STATEMENT OF PROBLEM The microstructural, physical, and optical properties of newly available highly-translucent zirconia ceramics have not been thoroughly investigated. PURPOSE The purpose of this in vitro study was to evaluate the microstructural, physical, and optical properties of current zirconia ceramics with different degrees of translucency and to compare the optical properties with lithium disilicate glass-ceramic at different thicknesses. MATERIAL AND METHODS Disk-shaped specimens (N=108) were prepared from 3 different monolithic zirconia ceramics: VITA YZ HT (YZ-HT), VITA YZ ST (YZ-ST), and VITA YZ XT (YZ-XT) and lithium disilicate glass-ceramic (IPS e-max CAD LT [IPS]) with a diameter of 14 mm and 3 different thicknesses (0.5, 1.0, and 1.5 mm ±0.02 mm). The microstructural features (grain size, elemental composition, phase identifications, and quantifications), physical properties (Vickers hardness and fracture toughness), and optical properties (translucency parameter and contrast ratio) were investigated. Data were analyzed using 1-way ANOVA, followed by the post hoc Tukey tests or Kruskal-Wallis and Mann-Whitney U tests (α=.05). RESULTS Differences in grain size, phase assemblages, fracture toughness, translucency parameter, and contrast ratio were found to be significant (P<.05). The average grain size was different for the 3 zirconia specimens with the following order: YZ-XT>YZ-ST>YZ-HT. The fracture toughness of YZ-HT was higher than that of YZ-ST and YZ-XT (P<.05). IPS with 0.5-mm thickness had the highest TP followed by YZ-XT and YZ-ST. The CR values were in the range of 0.54 to 0.91 (YZ-HT), 0.43 to 0.61 (YZ-ST), 0.29 to 0.45 (YZ-XT), and 0.27 to 0.53 (IPS), and all decreased with an increase in thickness. CONCLUSIONS Based on the results of the present study, the microstructural, physical, and optical properties of zirconia ceramics were affected by the changes in chemical composition and sintering parameters.
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Affiliation(s)
- Nazmiye Sen
- Doctoral Researcher, Department of Prosthodontics, School of Dentistry, University of Istanbul, Istanbul, Turkey.
| | - Sabire Isler
- Professor, Department of Prosthodontics, School of Dentistry, University of Istanbul, Istanbul, Turkey
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221
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Øilo M, Schriwer C, Flinn B, Gjerdet NR. Monolithic zirconia crowns – wall thickness, surface treatment and load at fracture. Biomater Investig Dent 2019. [DOI: 10.1080/26415275.2019.1642112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Affiliation(s)
- Marit Øilo
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA
| | - Christian Schriwer
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Brian Flinn
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA
| | - Nils Roar Gjerdet
- Department of Clinical Dentistry, Faculty of Medicine, University of Bergen, Bergen, Norway
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222
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Longhini D, Rocha C, de Oliveira LT, Olenscki NG, Bonfante EA, Adabo GL. Mechanical Behavior of Ceramic Monolithic Systems With Different Thicknesses. Oper Dent 2019; 44:E244-E253. [PMID: 31265354 DOI: 10.2341/18-083-l] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES This study assessed the fully stabilized zirconia (FSZ) Prettau Anterior, the partially stabilized zirconia (PSZ) Prettau, and the lithium disilicate IPS e.max CAD (LD) through microstructural and mechanical characterization and effect of thickness on fracture load of the ceramics. METHODS AND MATERIALS Disk-shaped specimens (12 mm diameter and 1.2 mm thickness) were prepared for biaxial flexural strength (BFS) and Weibull statistics (n=30). For the fracture load static test (FLST) and Weibull statistics (n=30), disk-shaped specimens 12 mm in diameter and thicknesses of 0.5 mm, 1 mm, and 1.5 mm were cemented on an epoxy-resin substrate. RESULTS BFS (MPa) results were PSZ: 683.0 ± 70.23; FSZ: 438.6 ± 64.1; and LD: 248.6 ± 37.3. One-way analysis of variance (ANOVA) for BFS was significant (p<0.001), and the Tukey post hoc test showed differences among all ceramics. There was difference in characteristic strength, but there was no difference in Weibull modulus. Two-way ANOVA for FLST was significant for ceramic (p<0001), thickness (p<0001), and interaction (p<0001). There was no difference among all ceramics at the 0.5 mm thickness. PSZ had higher values for the 1.0 mm and 1.5 mm thicknesses. LD of 1.5 mm thickness exhibited a higher FLST than FSZ. CONCLUSIONS PSZ had the highest BFS, but when cemented on a substrate, all ceramics with 0.5 mm thickness behaved similarly. Despite the lower BFS, LD had a fracture load similar or superior to FSZ when cemented on a substrate.
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223
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Bacchi A, Boccardi S, Alessandretti R, Pereira GKR. Substrate masking ability of bilayer and monolithic ceramics used for complete crowns and the effect of association with an opaque resin-based luting agent. J Prosthodont Res 2019; 63:321-326. [DOI: 10.1016/j.jpor.2019.01.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 01/08/2019] [Accepted: 01/17/2019] [Indexed: 11/30/2022]
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Abstract
Objective
This study evaluates the bond strength of two compositions of aesthetic translucent zirconia (TZ).
Materials and Methods
For this evaluation, test specimens were prepared from ICE Zirkon TZ and Prettau Anterior zirconia (PAZ) that were stored in distilled water at 37°C for two time periods: T1 (24 h) and T2 (90 days) to simulate aging. Two factors were evaluated for the samples—ceramic and aging time. The samples were subjected to tests of microshear strength and fracture type and were evaluated using scanning electron microscopy.
Results
The results were analyzed using the D'Agostino test, analysis of variance, and Tukey's test (
p
< 0.01). Statistically significant differences were observed for ceramic type and aging time.
Conclusion
The results showed that PAZ provides significantly superior performance to TZ at the two aging times evaluated.
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225
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Manziuc M, Gasparik C, Burde AV, Colosi HA, Negucioiu M, Dudea D. Effect of glazing on translucency, color, and surface roughness of monolithic zirconia materials. J ESTHET RESTOR DENT 2019; 31:478-485. [DOI: 10.1111/jerd.12493] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/11/2019] [Accepted: 05/20/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Manuela‐Maria Manziuc
- Department of Prosthetic Dentistry and Dental MaterialsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
| | - Cristina Gasparik
- Department of Prosthetic Dentistry and Dental MaterialsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
| | - Alexandru V. Burde
- Department of Prosthetic Dentistry and Dental MaterialsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
| | - Horaţiu A. Colosi
- Department of Medical Informatics and BiostatisticsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
| | - Marius Negucioiu
- Department of Prosthetic Dentistry and Dental MaterialsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
| | - Diana Dudea
- Department of Prosthetic Dentistry and Dental MaterialsIuliu Hatieganu University of Medicine and Pharmacy Cluj‐Napoca Romania
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226
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Zhang F, Reveron H, Spies BC, Van Meerbeek B, Chevalier J. Trade-off between fracture resistance and translucency of zirconia and lithium-disilicate glass ceramics for monolithic restorations. Acta Biomater 2019; 91:24-34. [PMID: 31034947 DOI: 10.1016/j.actbio.2019.04.043] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 04/07/2019] [Accepted: 04/22/2019] [Indexed: 02/04/2023]
Abstract
High strength and translucency are generally not coincident in one restorative material and there is still a continuous development for a better balance between these two properties. Zirconia and lithium-disilicate glass-ceramics are currently the most popular alternatives for monolithic restorations. In this work, the mechanical properties and more important, the slow crack growth (SCG) resistance, which rules long-term durability, were thoroughly studied for three zirconia ceramics stabilized by 3, 4 and 5 mol% yttria in comparison to lithium-disilicate glass-ceramic. Translucency versus strength maps revealed that the more translucent zirconia compositions (i.e. with higher yttria contents) fill the gap between the standard 3 mol% yttria stabilized zirconia (3Y-TZP) and lithium-disilicate. Moreover, increasing yttria content did not always result in lower strength, as values for 3 mol% and 4 mol% yttria were the same. Independent on the yttria contents, all zirconia showed similar relative susceptibility to SCG under static and cyclic conditions and were significantly more SCG-resistant than lithium-disilicate glass ceramic. A concern with higher yttria contents (5 and 4 mol%) however could lie in the higher sensitivity to defects, resulting in a larger scatter in strength. STATEMENT OF SIGNIFICANCE: In addition to the common investigations on the generally reported strength, toughness and translucency, V-KI diagrams (crack velocity versus stress-intensity factor) from fast fracture to threshold for three newly developed zirconia were directly measured by double torsion methods under static and cyclic loading conditions. The crack-growth mechanisms were analyzed in depth. Results were compared with another popular dental ceramic, namely lithium-disilicate glass-ceramic, revealing the pros and cons of polycrystalline and glass-ceramics in terms of long-term durability. This is the first time that V-KI curves are compared for the major ceramic and glass-ceramic used for dental restorations. Strength versus translucency maps for different CAD/CAM dental restorative materials were described, showing the current indication range for zirconia ceramics.
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227
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Masking ability of indirect restorative systems on tooth-colored resin substrates. Dent Mater 2019; 35:e122-e130. [DOI: 10.1016/j.dental.2019.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/28/2019] [Accepted: 03/04/2019] [Indexed: 11/21/2022]
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228
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Tangsatchatham S, Juntavee N. Flexural strength of various types of computerized machinable ceramic veneered to yttria stabilized tetragonal zirconia polycrystalline ceramic upon different hybridized techniques. Clin Cosmet Investig Dent 2019; 11:61-71. [PMID: 31118822 PMCID: PMC6498980 DOI: 10.2147/ccide.s196297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/13/2019] [Indexed: 11/29/2022] Open
Abstract
Objective: This study determined biaxial flexural strength (BFS) of computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic veneered yttria-stabilized tetragonal zirconia poly-crystalline (Y-TZP) related with hybridization techniques and veneering materials. Material and methods: One hundred and twenty zirconia Y-TZP (0.8 mm thick and 12 mm in diameter) were prepared and randomly divided into eight groups, to be conjugated with different veneering ceramics: Vitabloc (Vm), e.max-CAD (Em), Vita-Suprinity (Vs) and Celtra-Duo (Cd), using different hybridized techniques, CAD-bonded (Cb) versus CAD-fused (Cf). BFS was determined using piston on three balls and analyzed for Weilbull reliability. An analysis of variance (ANOVA) and Bonferroni’s multiple comparisons were determined for significant differences. Microscopic structures were examined with scanning electron microscope (SEM), along with X-ray diffraction (XRD). Results: BFS (mean±sd; MPa), Weibull modulus (m), and characteristic strength (σo) of each group were 630.46±65.08, 10.72, and 659.47 for VmCb, 709.03±102.88, 7.67, and 753.03 for VmCf, 651.83±69.48, 9.47, and 685.82 for EmCb, 721.17±121.28, 5.99, and 777.04 for EmCf, 692.83±89.10, 8.56, and 731.87 for VsCb, 888.61±164.26, 5.80, and 959.08 for VsCf, 687.17±59.39, 12.85, and 713.95 for CdCb, and 953.12±134.30, 7.97, and 1010.65 for CdCf. The BFS of ceramic veneered zirconia were significantly affected by different veneering ceramics, hybridized techniques, and their interactions (p<0.05). Cd showed highest BFS, followed by Vs, Em and Vm respectively. Both Cd and Vs showed significant higher BFS than Em and VM (p<0.05). No significant difference of BFS between Cd and Vs and between Em and Vm were indicated (p>0.05). Cf technique showed significantly higher impact on BFS than Cb (p<0.05). Veneering zirconia with either Cd or Vs using Cf technique revealed significantly higher flexural strength than others combinations (p<0.05). Conclusions: Type of veneering ceramics and hybridization techniques affected BFS of ceramic veneered Y-TZP. Veneering zirconia with either Cd or Vs using Cf-process produced superior BFS.
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Affiliation(s)
- Siripim Tangsatchatham
- Division of Biomaterial and Prosthodontic Research, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
| | - Niwut Juntavee
- Department of Prosthodontics, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
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Ruales-Carrera E, Cesar PF, Henriques B, Fredel MC, Özcan M, Volpato CAM. Adhesion behavior of conventional and high-translucent zirconia: Effect of surface conditioning methods and aging using an experimental methodology. J ESTHET RESTOR DENT 2019; 31:388-397. [PMID: 31099974 DOI: 10.1111/jerd.12490] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/22/2019] [Accepted: 05/02/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Evaluate the adhesive behavior of conventional and high-translucent zirconia after surface conditioning and hydrothermal aging. MATERIALS AND METHODS Conventional (ZrC) and high-translucent zirconia (ZrT) specimens were divided into six groups: without surface treatment (ZrC and ZrT), air-borne particle abrasion with 50-μm Al2 O3 sized particles (ZrC-AO and ZrT-AO), and tribochemical treatment with 30-μm silica modified Al2 O3 sized particles (ZrC-T and ZrT-T). Zirconia specimens were treated using an MDP-containing universal adhesive and bonded to two resins blocks with an adhesive luting cement. Microbar specimens with cross-sectioned areas of 1 mm2 were achieved. Half of the microbars were subjected to hydrothermal aging. Bond strength was evaluated by microtensile bond strength test and statistically evaluated by the Weibull analysis. RESULTS Roughness of the ZrC-AO and ZrT-AO groups were statistically higher. Bond strength analysis revealed higher bond strength for ZrC-AO and ZrC-T groups compared to ZrT-AO and ZrT-T, respectively. Mixed failure was the most frequent for the mechanically treated groups, while no cohesive failures were obtained. CONCLUSION Lower values of bond strength were obtained for the mechanically treated high-translucent zirconia groups when compared to their conventional zirconia counterparts. Mechanical surface treatment significantly improved the bond strength to conventional and high-translucent zirconia. CLINICAL SIGNIFICANCE Mechanical surface treatment (air-borne particle abrasion or tribochemical treatment) associated with the use of universal adhesives containing MDP could provide a durable bonding to conventional and high-translucent zirconia.
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Affiliation(s)
- Edwin Ruales-Carrera
- Department of Dentistry, Center for Education and Research in Dental Implants (CEPID), Federal University of Santa Catarina, Florianópolis, Brazil
| | - Paulo F Cesar
- Department of Dental Materials and Oral Biology, University of São Paulo, São Paulo, Brazil
| | - Bruno Henriques
- Ceramic and Composite Materials Research Laboratory (CERMAT), Federal University of Santa Catarina, Florianópolis, Brazil
| | - Márcio C Fredel
- Ceramic and Composite Materials Research Laboratory (CERMAT), Federal University of Santa Catarina, Florianópolis, Brazil
| | - Mutlu Özcan
- Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, University of Zurich, Zurich, Switzerland
| | - Claudia A M Volpato
- Department of Dentistry, Federal University of Santa Catarina, Florianópolis, Brazil
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LE M, Larsson C, Papia E. Bond strength between MDP-based cement and translucent zirconia. Dent Mater J 2019; 38:480-489. [PMID: 31105161 DOI: 10.4012/dmj.2018-194] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The purpose was to evaluate the bond strength between adhesive cement and translucent zirconia in comparison to conventional zirconia. Four brands of translucent zirconia (BruxZir® HT, Lava™ Plus, Prettau® Anterior, and Prettau® Zirconia) and one conventional zirconia (Kavo Everest® ZS) were evaluated. Specimens were divided into groups depending on the pretreatment of the cementation surface of the zirconia: as-produced, hydrofluoric acid treatment, or sandblasted. The groups underwent three different procedures of artificial aging: water storage (24 h), 5,000 thermocycles, or long-term aging, (water storage 150 days including 37,500 thermocycles) before shear bond strength testing. Sandblasting treatment increased the bond strength significantly for all the brands of zirconia, irrespective of artificial aging procedures, in comparison to the control group. Bond strength between adhesive cement to translucent zirconia is equivalent to conventional zirconia. Sandblasting creates a cementation surface that is more durable than as-produced or hydrofluoric-acid-treated, irrespective of type of zirconia.
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Affiliation(s)
- Minh LE
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University
| | - Christel Larsson
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University
| | - Evaggelia Papia
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University
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231
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Tabatabaian F, Aflatoonian K, Namdari M. Effects of veneering porcelain thickness and background shade on the shade match of zirconia-based restorations. J Dent Res Dent Clin Dent Prospects 2019; 13:68-74. [PMID: 31217922 PMCID: PMC6571521 DOI: 10.15171/joddd.2019.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 03/17/2019] [Indexed: 11/28/2022] Open
Abstract
Background. Effects of veneering porcelain thickness and background shade on the shade match of zirconia-based restorations are unclear. The aim of this study was to evaluate the impacts of veneering porcelain thickness and background shade on the shade match of zirconia-based restorations.
Methods. Forty A2 shade veneered zirconia disk specimens (10 mm in diameter) were fabricated, with veneering porcelain thicknesses of 1.6, 1.8, 2.0 and 2.2 mm. Three backgrounds were made of A2 shade composite resin (A2), nickel-chromium alloy (NC) and amalgam (AM). The veneered zirconia specimens were placed on the backgrounds. CIELab values were measured with a spectrophotometer. ΔE values were measured to determine color differences between the specimens and the A2 VITA classical shade (target shade). ΔE values were compared with an acceptability threshold (ΔE=3.7). Repeated measures ANOVA, Bonferroni, and 1-sample t-test were used to analyze data (P<0.05).
Results. Mean ΔE values ranged between 1.9 and 5.0. The veneering porcelain thickness, the background shade and their interaction affected the ΔE (P<0.0001). The minimum veneering porcelain thickness for the shade match was 2 mm for NC and 1.8 mm for AM.
Conclusion. Veneering porcelain thickness and background shade affected the shade match of zirconia-based restorations. With dark-shaded backgrounds, the amount of veneering porcelain thickness needed for the shade match might be beyond acceptable clinical limits. Tooth-shaded backgrounds are esthetically advocated rather than dark-shaded backgrounds in zirconia-based restorations.
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Affiliation(s)
- Farhad Tabatabaian
- Department of Prosthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Mahshid Namdari
- Department of Community Oral Health, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Abstract
This review highlights ceramic material options and their use. The newer high-strength ceramics in monolithic form have gained popularity despite the lack of long-term clinical data to support this paradigm shift. Although there are some encouraging clinical data available, there is a need to develop laboratory simulation models that can help predict long-term clinical performance for ceramic and adhesive cements.
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Affiliation(s)
- Robert R Seghi
- Division of Restorative and Prosthetic Dentistry, The Ohio State University College of Dentistry, 305 West 12th Avenue, Room 3005H, Columbus, OH 43210-1267, USA.
| | - Diana Leyva Del Rio
- Oral Biology, The Ohio State University College of Dentistry, 305 West 12th Avenue, Room 3037D, Columbus, OH 43210-1267, USA
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Coskun M, Sarı F. Effects of Speed Sintering on Multilayered Monolithic Zirconia. CUMHURIYET DENTAL JOURNAL 2019. [DOI: 10.7126/cumudj.510393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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López‐Píriz R, Cabal B, Goyos‐Ball L, Fernández A, Bartolomé JF, Moya JS, Torrecillas R. Current state‐of‐the‐art and future perspectives of the three main modern implant‐dentistry concerns: Aesthetic requirements, mechanical properties, and peri‐implantitis prevention. J Biomed Mater Res A 2019; 107:1466-1475. [DOI: 10.1002/jbm.a.36661] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/24/2019] [Accepted: 02/14/2019] [Indexed: 12/29/2022]
Affiliation(s)
- Roberto López‐Píriz
- Nanomaterials and Nanotechnology Research Centre (CINN)Universidad de Oviedo (UO), Consejo Superior de Investigaciones Científicas (CSIC), Principado de Asturias (PA) Avenida de la Vega 4‐6, El Entrego Asturias, 33940 Spain
| | - Belén Cabal
- Nanomaterials and Nanotechnology Research Centre (CINN)Universidad de Oviedo (UO), Consejo Superior de Investigaciones Científicas (CSIC), Principado de Asturias (PA) Avenida de la Vega 4‐6, El Entrego Asturias, 33940 Spain
| | - Lidia Goyos‐Ball
- Nanoker Research, Pol. Ind. Olloniego, Department of Research and Development Parcela 22A, Nave 5, 33660, Oviedo Spain
| | - Adolfo Fernández
- Nanomaterials and Nanotechnology Research Centre (CINN)Universidad de Oviedo (UO), Consejo Superior de Investigaciones Científicas (CSIC), Principado de Asturias (PA) Avenida de la Vega 4‐6, El Entrego Asturias, 33940 Spain
| | - José F. Bartolomé
- Instituto de Ciencia de Materiales de Madrid (ICMM), Department of Energy, Environment and Health, Consejo Superior de Investigaciones Científicas (CSIC) Calle Sor Juana Inés de la Cruz 3, Madrid, 28049 Spain
| | - Jose S. Moya
- Nanomaterials and Nanotechnology Research Centre (CINN)Universidad de Oviedo (UO), Consejo Superior de Investigaciones Científicas (CSIC), Principado de Asturias (PA) Avenida de la Vega 4‐6, El Entrego Asturias, 33940 Spain
| | - Ramón Torrecillas
- Nanomaterials and Nanotechnology Research Centre (CINN)Universidad de Oviedo (UO), Consejo Superior de Investigaciones Científicas (CSIC), Principado de Asturias (PA) Avenida de la Vega 4‐6, El Entrego Asturias, 33940 Spain
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New multi-layered zirconias: Composition, microstructure and translucency. Dent Mater 2019; 35:797-806. [PMID: 30853208 DOI: 10.1016/j.dental.2019.02.017] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 02/13/2019] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To fully realize the range of indication and clinical advantages of the new multi-layered zirconias, a comprehensive understanding of their chemical composition, microstructure, low temperature degradation (LTD) resistance, and translucency properties is paramount. METHODS A zirconia system (Katana, Kuraray Noritake), including 3 distinct grades of multi-layered zirconias, was selected for study: Ultra Translucent Multi-layered zirconia (UTML), Super Translucent Multi-layered zirconia (STML), and Multi-layered zirconia (ML). For different materials and their individual layers, the chemical composition, zirconia phase fractions, and microstructure were determined by X-ray fluorescence (XRF), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). Also, their resistance to LTD and translucency properties were characterized. RESULTS Our findings revealed no major differences amongst layers, but the 3 materials were very distinct-UTML: 5Y-PSZ (5 mol% yttria-partially-stabilized zirconia) with ˜75 wt% cubic content and a 4.05 (±0.85) μm average grain size, STML: 4Y-PSZ with ˜65 wt% cubic content and a 2.81 (±0.17) μm average grain size, and ML: 3Y-PSZ with <50 wt% cubic content and a 0.63 (±0.03) μm average grain size. After water aging at 120 °C for 12 h, greater monoclinic content was found in ML. UTML and STML did not show detectable monoclinic phase. The translucency was similar among layers, and also between UTML and STML, which were superior to ML. SIGNIFICANCE For each multi-layered zirconia grades, the layers are only differed in pigment types and contents, which yield remarkably natural shade gradients. Also, despite the significant compositional difference between STML and UTML, both materials showed similar translucencies.
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Enamel wear and aging of translucent zirconias: In vitro and clinical studies. J Prosthet Dent 2019; 121:417-425. [DOI: 10.1016/j.prosdent.2018.04.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 04/23/2018] [Accepted: 04/23/2018] [Indexed: 11/24/2022]
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Attachoo S, Juntavee N. Role of sintered temperature and sintering time on spectral translucence of nano-crystal monolithic zirconia. J Clin Exp Dent 2019; 11:e146-e153. [PMID: 30805119 PMCID: PMC6383898 DOI: 10.4317/jced.55497] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 01/14/2019] [Indexed: 02/04/2023] Open
Abstract
Background Sintering process is accountable for aesthetic appearance of zirconia restoration. This study appraised the effect of different sintering procedure via sintered temperatures and sintering times on spectral translucence of monolithic zirconia. Material and Methods One hundred and thirty five monolithic zirconia specimens (width, length, thickness = 10, 20, 1.5 mm) were prepared from yttrium-stabilized tetragonal zirconia polycrystalline (Y-TZP, Ceramill®) and unintentionally divided into nine groups to be sintered at different temperatures [decreasing- (SD, 1350°C), regular- (SR, 1450°C), and increasing- (SI, 1550°C) sintering temperature] and different sintering times [shortening- (HS, 60 min), regular- (HR, 120 min), and prolong- (HP, 180 min) sintering time]. Spectral translucence was determined by using spectrophotometer and calculated for translucency parameter (TP). The surface topography and grain size were evaluated by using a scanning electron microscope (SEM). Crystalline structures of monoclinic (m) and tetragonal (t) phases were determined by using the X-ray diffraction (XRD). An analysis of variance (ANOVA) was used to determine for significant differences of translucence upon different sintering processes (α=0.05). Results The mean, standard deviation of TP were 3.22±0.12 for SRHP, 3.14±0.18 for SIHS, 3.04±0.17 for SRHR, 2.94±0.18 for SRHS, 2.93±0.17 for SIHR, 2.67±0.15 for SIHP, 1.91±0.17 for SDHP, 1.34±0.21 for SDHR and 0.10±0.01 for SDHS. Spectral translucence was significantly affected by altering sintering temperatures and holding times (p<0.05). Enlargement of grain size and increasing t→m phase metamorphosis related with upraising sintered temperatures and extending sintered holding times were signified. Conclusions Altering sintering parameters affected spectral translucence of zirconia. Upraising sintered temperature to SR and prolonging sintering time to HP were advocated to enhance spectral translucence of nano-crystal monolithic zirconia, and advised to accomplished aesthetic appearance of restoration in clinical practice. Key words:CAD-CAM, sintering process, translucency, zirconia.
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Affiliation(s)
- Surawut Attachoo
- Division of Biomaterials and Prosthodontics Research, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
| | - Niwut Juntavee
- Department of Prosthodontics, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
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Turgut S, Kılınç H, Bağış B. Effect of UV aging on translucency of currently used esthetic CAD‐CAM materials. J ESTHET RESTOR DENT 2019; 31:147-152. [DOI: 10.1111/jerd.12460] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 12/05/2018] [Accepted: 01/23/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Sedanur Turgut
- Faculty of Dentistry, Prosthodontics DepartmentKaradeniz Technical University Trabzon Turkey
| | - Hamiyet Kılınç
- Faculty of Dentistry, Prosthodontics DepartmentBolu Abant Izzet Baysal University Bolu Turkey
| | - Bora Bağış
- Faculty of Dentistry, Prosthodontics Departmentİzmir Katip Çelebi University Turkey
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Tabatabaian F, Jafari A, Namdari M, Mahshid M. Influence of coping and veneer thickness on the color of zirconia-based restorations on different implant abutment backgrounds. J Prosthet Dent 2019; 121:327-332. [DOI: 10.1016/j.prosdent.2018.02.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/27/2018] [Accepted: 02/28/2018] [Indexed: 11/26/2022]
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241
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Optical properties of translucent zirconia: A review of the literature. EUROBIOTECH JOURNAL 2019. [DOI: 10.2478/ebtj-2019-0005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Abstract
Translucent monolithic zirconia is the newest option of zirconia-based ceramics, which aimed to substitute the opaque classic yttria-stabilized tetragonal zirconia polycrystal (Y-TZPs) in more demanding esthetic cases.
The aim of this review was to assess the available literature regarding the optical, chemical and mechanical properties of translucent zirconia ceramics.
This systematic review was developed according to the PRISMA (Preferred Reporting Items for Systematic Review and Meta-analysis) guidelines. An electronic literature search was undertaken through Medline (National Library of Medicine) via PubMed to identify relevant articles, published in the interval 2010-2018. The search was limited to the English language publications, in vitro studies of color and microstructure of translucent zirconia material.
Yttria-stabilized tetragonal zirconia polycrystals (Y-TZPs) has excellent mechanical properties, but its intense white color and high opacity represent an esthetic limit. Cubic zirconia represents a new generation of dental ceramics with molecular structure and physical properties different from the conventional zirconia. Dental manufacturers created new formulations of this restorative material, introducing new cubic varieties of zirconia with improved optical properties. Translucent monolithic zirconia provides a new restorative option that combines strength with improved esthetics, due to its increased translucency. Translucent zirconia is indicated for anterior and posterior restorations but should be used carefully for discolored teeth, because the background color can affect the final esthetic appearance of the restoration.
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242
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Volpato CAM, Carvalho ÓSN, Pereira MRDC, Correia Pereira da Silva FS. Evaluation of the color and translucency of glass-infiltrated zirconia based on the concept of functionally graded materials. J Prosthet Dent 2019; 121:547.e1-547.e7. [PMID: 30661878 DOI: 10.1016/j.prosdent.2018.09.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 09/20/2018] [Accepted: 09/20/2018] [Indexed: 11/26/2022]
Abstract
STATEMENT OF PROBLEM Infiltrated zirconia has promising mechanical properties. However, information about its optical behavior is scarce. PURPOSE The purpose of this in vitro study was to evaluate the color and translucency of zirconia submitted to infiltration and aging. MATERIAL AND METHODS Sixty zirconia disks were machined. Ten disks received no treatment (NT group), 10 disks were immersed in a coloring liquid (A2 group), and 10 disks were immersed in a fluorescent liquid (F group). The other 30 disks were submitted to the same treatments plus glass infiltration (NT+I, A2+I, and F+I groups). The coordinates L*, a*, and b* and the Y tristimulus values were obtained to calculate the color (ΔE00), lightness, chroma, and hue differences; the translucency parameter (TP); and the contrast ratio (CR) associated with the specimens. After aging in an autoclave for 4 hours (T1), new measurements were made. Two- and 3-way ANOVAs were used to analyze color differences, TP, and CR. The lightness, chroma, and hue differences were evaluated by a repeated measures ANOVA. Multiple comparisons were made with the Tukey honestly significant difference (HSD) test (α=.05). RESULTS The greatest color differences were observed in the A2+I group (11.23 ΔE00) (P<.001). Aging affected the chroma of the colored groups (P=.013 and P=.001) but did not affect their translucency (P=.347 for TP and P=.132 for CR). The greatest TP values were found in the NT and NT+I groups (2.54 and 2.34, respectively), whereas the CR was equal to or close to 1 in all groups. CONCLUSIONS Color differences were observed in the glass-infiltrated groups. The TP and CR were affected by infiltration. Aging did not influence the optical behavior of the specimens.
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Affiliation(s)
| | - Óscar Samuel Novais Carvalho
- Assistant Professor, Department of Mechanical Engineering, University of Minho (UMinho), Azurém Campus, Guimarães, Portugal
| | - Mário Rui da Cunha Pereira
- Assistant Professor, Department of Physics, University of Minho (UMinho), Gualtar Campus, Braga, Portugal
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Ruales-Carrera E, Engler MLPD, Vaz P, Özcan M, Volpato CAM. Esthetic and functional rehabilitation of bilateral congenital absence of maxillary lateral incisors: Minimally invasive surgical and prosthetic approach. J ESTHET RESTOR DENT 2018; 31:5-12. [PMID: 30499164 DOI: 10.1111/jerd.12448] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 01/18/2023]
Abstract
OBJECTIVE Congenital absence of maxillary lateral incisors is a frequent clinical challenge which must be solved by a multidisciplinary approach in order to obtain an esthetic and functional restorative treatment. Noninvasive treatments, that are in accordance with the patients' expectations, should be the first therapeutic alternative. If the deciduous tooth is present, minimally invasive dental extraction followed by immediate dental implant placement and provisional restoration is indicated. In this restorative treatment, an adequate emergency profile can be achieved by peri-implant soft-tissue-conditioning techniques. Moreover, the association of restorative materials, such as composite resins and dental ceramics, provides more predictable esthetic results. CLINICAL CONSIDERATIONS The present case report presents a rehabilitation of bilateral congenital absence of maxillary lateral incisors through a multidisciplinary approach. Dental implants, long-term provisional restoration, tooth bleaching, minimally veneered high-translucent monolithic zirconia crowns, feldspathic veneers, and composite restorations were used by the dental team to achieve the expected functional and esthetic outcomes. CONCLUSIONS Different treatment modalities are available for the rehabilitation of congenital absence of teeth. However, it is important that a dental team consider performing minimally invasive treatments, as many of these treatments are done on young patients. CLINICAL SIGNIFICANCE Patient-centered treatments involving minimally invasive approaches in a multidisciplinary environment would be appropriate in order to achieve predictable results.
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Affiliation(s)
- Edwin Ruales-Carrera
- Department of Dentistry, Center for Education and Research on Dental Implants (CEPID), Federal University of Santa Catarina, Florianópolis, Brazil
| | - Madalena Lucia Pinheiro Dias Engler
- Department of Dentistry, Center for Education and Research on Dental Implants (CEPID), Federal University of Santa Catarina, Florianópolis, Brazil
| | - Paula Vaz
- Department of Orofacial Genetics, Faculty of Dental Medicine, University of Porto, Porto, Portugal
| | - Mutlu Özcan
- Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, University of Zurich, Zurich, Switzerland
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Souza R, Barbosa F, Araújo G, Miyashita E, Bottino MA, Melo R, Zhang Y. Ultrathin Monolithic Zirconia Veneers: Reality or Future? Report of a Clinical Case and One-year Follow-up. Oper Dent 2018; 43:3-11. [PMID: 29284106 DOI: 10.2341/16-350-t] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Yttria-stabilized polycrystalline zirconia ceramics have greatly advanced over the past few years. High-translucent zirconia is a newly introduced ceramic that affords high strength and esthetics and that has significantly increased the clinical indications of monolithic zirconia restorations. Thus, the purpose of this case report was to evaluate the performance of ultrathin monolithic zirconia veneers adhesively luted to enamel surfaces after minimally invasive preparations; in addition, we aimed at presenting a clinical protocol for zirconia surface treatment in order to promote bonding effectiveness to resin cement. This type of restoration presented very acceptable esthetic results and decreased the risk of fracturing the veneer during try-in and clinical use. The results were still satisfactory after one-year follow-up. However, randomized, prospective, controlled clinical trials are required to determine the long-term clinical durability of this treatment.
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Kusaba K, Komine F, Honda J, Kubochi K, Matsumura H. Effect of preparation design on marginal and internal adaptation of translucent zirconia laminate veneers. Eur J Oral Sci 2018; 126:507-511. [PMID: 30289591 DOI: 10.1111/eos.12574] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2018] [Indexed: 11/28/2022]
Abstract
This study investigated the effect of preparation design on the marginal and internal adaptation of laminate veneers (LVs) fabricated from translucent zirconia. Thirty-three resin teeth were prepared for LVs of three designs: window preparation (WP); incisal shoulder preparation (ISP); and incisal palatal chamfer preparation (IPP). Marginal adaptation was evaluated by measuring the vertical discrepancy between the LV margin and the finish line at 60 points. The internal adaptation was assessed by measuring the internal space width as the distance between the LV and the tooth at cervical, central, and incisal sites after sectioning. At the incisal, mesial, and distal sites, mean marginal discrepancies were significantly lower in the WP group than in the other two groups; the IPP group had the highest marginal discrepancies. At incisal sites, the median internal space was significantly higher in the IPP group than in the WP and ISP groups and higher in the ISP group than in the WP group. At the incisal site, marginal and internal adaptations were better for the non-overlap translucent zirconia LV design (WP) than for the overlap designs (ISP and IPP). The characteristics of the translucent zirconia LVs used in the present study indicate acceptable clinical performance.
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Affiliation(s)
- Kosuke Kusaba
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan
| | - Futoshi Komine
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan
| | - Junichi Honda
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan
| | - Kei Kubochi
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan
| | - Hideo Matsumura
- Department of Fixed Prosthodontics, Nihon University School of Dentistry, Tokyo, Japan
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Yan J, Kaizer MR, Zhang Y. Load-bearing capacity of lithium disilicate and ultra-translucent zirconias. J Mech Behav Biomed Mater 2018; 88:170-175. [PMID: 30173069 DOI: 10.1016/j.jmbbm.2018.08.023] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/10/2018] [Accepted: 08/19/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the load-bearing capacity of monolithic lithium disilicate (LiDi - IPS e.max CAD) and novel ultra-translucent zirconia restorative systems of various compositions: 5Y-PSZ (5 mol% yttria-partially-stabilized zirconia) and 4Y-PSZ (4 mol% yttria-partially-stabilized zirconia); relative to a 3Y-TZP (3 mol% yttria-stabilized zirconia) control. MATERIALS AND METHODS Experiments were carried out with 10 disc specimens (Ø12 ×1 mm) per ceramic material. The zirconia intaglio surface (as machined) was sandblasted (50 µm Al2O3 at 2 bar), while LiDi was etched with 5% HF for 20 s. The ceramic discs were then adhesively bonded onto a dentin-like substrate (G10, a high-pressure fiberglass material) using Multilink Automix cement and Monobond Plus primer, producing a ceramic/cement/dentin-like substrate trilayer structure. The bonded specimens were stored in water for 3 days at 37 °C prior to a Hertzian indentation flexural radial fracture test. The plate-on-foundation theory was used to validate the load-bearing capacity of the trilayer systems based on the flexural tensile stress at the ceramic intaglio (cementation) surface-a cause for bulk fracture of ceramic onlays. RESULTS The experiment data showed that, when bonded to and supported by a dentin-like substrate, the load-bearing capacity of LiDi (872 N) is superior to the 5Y-PSZ (715 N) and can even reach that of 4Y-PSZ (864 N), while 3Y-TZP still holds the highest load-bearing capacity (1195 N). Theoretical analyses agree with experimental observations. The translucency of 5Y-PSZ approaches that of LiDi, which are superior to both 4Y-PSZ and 3Y-TZP. CONCLUSIONS When adhesively bonded to and supported by dentin, lithium disilicate exhibits similar load-bearing properties to 4Y-PSZ but much better than 5Y-PSZ.
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Affiliation(s)
- Jing Yan
- Department of Biomateirals & Biomimetics, New York University College of Dentistry, New York, NY 10010, United States
| | - Marina R Kaizer
- Department of Biomateirals & Biomimetics, New York University College of Dentistry, New York, NY 10010, United States
| | - Yu Zhang
- Department of Biomateirals & Biomimetics, New York University College of Dentistry, New York, NY 10010, United States.
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Juntavee N, Attashu S. Effect of sintering process on color parameters of nano-sized yttria partially stabilized tetragonal monolithic zirconia. J Clin Exp Dent 2018; 10:e794-e804. [PMID: 30305879 PMCID: PMC6174024 DOI: 10.4317/jced.55034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/05/2018] [Indexed: 02/04/2023] Open
Abstract
Background Sintering process is responsible for aesthetic of zirconia restoration. This study evaluated the effect of different sintering temperatures and sintered-holding times on color parameters of monolithic zirconia. Material and Methods One hundred and thirty five zirconia bar specimens (width-length-thickness = 10×20×1.5 mm) were prepared from yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramic and randomly divided into nine groups to be sintered at different temperatures [decreasing- (SD, 1350°C), regular- (SR, 1450°C), and increasing- (SI, 1550°C) sintering temperature] and different sintered-holding times [shortening- (HS, 60 min), regular- (HR, 120 min), and prolonged- (HP, 180 min) sintered-holding time]. Color appearance (ΔE), translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) were determined with spectrophotometer. An analysis of variance (ANOVA) and Tukey’s multiple comparisons were used to determine for statistically significant difference of color parameters (α=0.05). Crystal sizes were microscopically examined using scanning electron microscope (SEM), and phase composition of zirconia was determined using X-ray diffraction (XRD). Results The mean±sd for ΔE, TP, CR, OP were 82.28±1.27, 1.4±0.13, 0.982±0.004, 1.25±0.15 for SDHS, 78.38±0.74, 2.16±0.10, 0.967±0.005, 1.90±0.11 for SDHR, 74.43±0.91, 2.24±0.10, 0.964±0.004, 1.94±0.09 for SDHP, 76.31±1.22, 3.03±0.10, 0.945±0.003, 2,50±0.09 for SRHS, 74.51±1.27, 3.19±0.17, 0.942±0.003, 2.65±0.16 for SRHR, 73.94±0.49, 3.42±0.10, 0.937±0.003, 2,83±0.09 for SRHP, 76.30±0.43, 3.16±0.09, 0.937±0.002, 2.48±0.09 for SIHS 76.73±1.15, 3.05±0.20, 0.939±0.005, 2.38±0.17 for SIHR, and 75.32±1.37, 2.95±0.18, 0.942±0.006, 2.33±0.15 for SIHP. The ΔE, TP, CR, and OP were significantly affected by altering sintering temperatures and holding times (p<0.05). Increasing sintering temperature and extending sintering time significantly improved color appearance, translucency, contrast, and opalescence of Y-TZP (p<0.05) as evidenced by enlarging grain size and increasing t→m phase shift. Conclusions Raising sintering temperature and prolonging sintering time lead to better color appearance, translucency, contrast and opalescence of nano-sized monolithic Y-TZP, and are suggested for sintering process. Key words:Color appearance, contrast, monolithic zirconia, opalescence, sintering process, translucency.
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Affiliation(s)
- Niwut Juntavee
- Department of Prosthodontics, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
| | - Surawut Attashu
- Division of Biomaterials and Prosthodontics Research, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
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Mühlemann S, Benic GI, Fehmer V, Hämmerle CHF, Sailer I. Randomized controlled clinical trial of digital and conventional workflows for the fabrication of zirconia-ceramic posterior fixed partial dentures. Part II: Time efficiency of CAD-CAM versus conventional laboratory procedures. J Prosthet Dent 2018; 121:252-257. [PMID: 30037692 DOI: 10.1016/j.prosdent.2018.04.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 04/19/2018] [Accepted: 04/19/2018] [Indexed: 10/28/2022]
Abstract
STATEMENT OF PROBLEM Clinical trials are needed to evaluate the digital and conventional fabrication technology for providing fixed partial dentures (FPDs). PURPOSE The purpose of the second part of this clinical study was to compare the laboratory production time for tooth-supported, 3-unit FPDs by means of computer-aided design and computer-aided manufacturing (CAD-CAM) systems and a conventional workflow. In addition, the quality of the 3-unit framework of each treatment group was evaluated clinically. MATERIAL AND METHODS For each of 10 participants, a 3-unit FPD was fabricated. Zirconia was used as the framework material in the CAD-CAM systems and included Lava C.O.S. CAD software (3M) and centralized CAM (group L); CARES CAD software (Institut Straumann AG) and centralized CAM (group iT); and CEREC Connect CAD software (Dentsply Sirona) and centralized CAM (group C). The noble metal framework in the conventional workflow (group K) was fabricated by means of the traditional lost-wax technique. All frameworks were evaluated clinically before veneering. The time for the fabrication of the cast, the 3-unit framework, and the veneering process was recorded. In addition, chairside time during the clinical appointment for the evaluation of the framework was recorded. The paired Wilcoxon test together with appropriate Bonferroni correction was applied to detect differences among treatment groups (α=.05). RESULTS The total effective working time (mean ±standard deviation) for the dental technician was 220 ±29 minutes in group L, 217 ±23 minutes in group iT, 262 ±22 minutes in group C, and 370 ±34 minutes in group K. The dental technician spent significantly more time in the conventional workflow than in the digital workflow, independent of the CAD-CAM systems used (P<.001). CONCLUSIONS Irrespective of the CAD-CAM system, the overall laboratory time for the dental technician was significantly less for a digital workflow than for the conventional workflow.
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Affiliation(s)
- Sven Mühlemann
- Senior Teaching and Research Assistant, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
| | - Goran I Benic
- Senior Teaching and Research Assistant, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Vincent Fehmer
- Master Dental Technician, Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Christoph H F Hämmerle
- Professor, Clinic of Fixed and Removable Prosthodontics and Dental Material Science, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Irena Sailer
- Professor, Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
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Influence of polymerization time on properties of dual-curing cements in combination with high translucency monolithic zirconia. J Prosthodont Res 2018; 62:468-472. [PMID: 29983378 DOI: 10.1016/j.jpor.2018.06.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 06/05/2018] [Accepted: 06/10/2018] [Indexed: 11/27/2022]
Abstract
PURPOSE The aim of this in vitro study was to assess conversion degree (DC), micro-hardness (MH) and bond strength of two dual-curing resin cements employed under translucent monolithic zirconia irradiated with different time protocols. METHODS 84 square shaped samples of 1mm thickness were prepared from high translucency zirconia blocks and divided into two groups (n=24) according to the cement employed: (1) Rely-X Ultimate; (2) Panavia SA. Each group was further divided into 3 subgroups (n=8) according to the irradiation time: (a) no light; (b) 20s; (c) 120s. Light curing was performed 60s after the sample was placed on the diamond support of a FT-IR spectrophotometer with a high power multiLED lamp. Final DC% were calculated after 10min. After 24h, Vickers Test on the cement layer was performed. The same protocol was used to lute composite cylinders in order to evaluate microshear bond-strength test. ANOVA and Bonferroni tests were performed to find differences between MH and bond-strength to zirconia, while for DC% the Scheirer-Ray-Hare two-way test was used. RESULTS The two cements reached higher DC% in subgroup (b) and (c). As concern MH, statistics showed an increase in curing time was able to improve MH significantly. Bond-strength was not affected by irradiation time only for Panavia SA. CONCLUSIONS The first null hypothesis has to be rejected since DC% and MH of the dual-cements tested were influenced by the curing time. The second null hypothesis is partially rejected since the bond strength was influenced by the curing time only for Rely-X Ultimate.
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NISHIOKA G, PROCHNOW C, FIRMINO A, AMARAL M, BOTTINO MA, VALANDRO LF, Renata Marques de MELO. Fatigue strength of several dental ceramics indicated for CAD-CAM monolithic restorations. Braz Oral Res 2018; 32:e53. [DOI: 10.1590/1807-3107bor-2018.vol32.0053] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/04/2018] [Indexed: 11/21/2022] Open
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