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Vardhaman S, Borba M, Kaizer MR, Kim DK, Zhang Y. Optical and Mechanical Properties of the Multi-Transition Zones of a Translucent Zirconia. J ESTHET RESTOR DENT 2024. [PMID: 39325338 DOI: 10.1111/jerd.13319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 07/30/2024] [Accepted: 09/06/2024] [Indexed: 09/27/2024]
Abstract
OBJECTIVE To characterize the composition, flexure resistance, and optical properties of a multilayer translucent zirconia in relation to its multi-transition zones. MATERIALS AND METHODS A multilayer zirconia (5Y/4Y) and a conventional 3 mol% yttria partially stabilized zirconia (3Y) were investigated. Bar-shaped specimens were obtained from the enamel and dentin layers, and the vertical cross-section of 5Y/4Y (N = 10). A four-point flexural (σf) test was performed using a universal testing machine (1.0 mm/min). Plate-shaped specimens (N = 6) were also produced from the enamel, transition 1, transition 2, and dentin layers. Translucency parameters (TPab and TP00) were determined using a dental spectrophotometer (N = 6). X-ray fluorescence and X-ray diffraction techniques were used to analyze elemental (N = 2) and phase compositions (N = 2), respectively. Data were analyzed using analysis of variance (ANOVA) and Tukey's test (α = 0.05). RESULTS The yttrium content and σf varied between layers of 5Y/4Y. 3Y had the highest σf, followed by dentin. Enamel and cross-section showed lower and statically similar σf. 3Y and dentin groups had similar but statistically lower TPab and TP00 than the enamel. CONCLUSIONS Different layers of multilayered zirconia have distinct compositions, which affect their mechanical and optical properties. The weak enamel layer compromises the mechanical properties of cross-sectional specimens. CLINICAL SIGNIFICANCE The development of novel cubic-containing multilayer zirconia ceramics to produce monolithic restorations brings new challenges to dental clinicians and laboratory technicians. The CAD/CAM design of multilayered 5Y/4Y restorations should consider the esthetic and mechanical requirements of each clinical case, as different properties are found in the different layers of these materials.
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Affiliation(s)
- Sonaj Vardhaman
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- College of Dental Medicine, Columbia University, New York, New York, USA
| | - Marcia Borba
- University of Manchester, Manchester, UK
- University of Passo Fundo, Passo Fundo, Brazil
| | - Marina R Kaizer
- Centre for Rural Dentistry and Oral Health, Charles Sturt University, Orange, New South Wales, Australia
- Post-Graduate Program in Dentistry, Universidade Positivo, Curitiba, Paraná, Brazil
| | - Do Kyung Kim
- Department of Materials Science and Engineering, KAIST, Daejeon, South Korea
| | - Yu Zhang
- Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Kang CM, Peng TY, Wu YA, Hsieh CF, Chi MC, Wu HY, Lin ZC. Comparison of Optical Properties and Fracture Loads of Multilayer Monolithic Zirconia Crowns with Different Yttria Levels. J Funct Biomater 2024; 15:228. [PMID: 39194666 DOI: 10.3390/jfb15080228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2024] [Revised: 08/13/2024] [Accepted: 08/14/2024] [Indexed: 08/29/2024] Open
Abstract
Multilayer monolithic zirconia, which incorporates polychromatic layers that mimic natural tooth gradients, offers enhanced aesthetics and functionality while reducing debonding risks and improving fabrication efficiency. However, uncertainties remain regarding the fracture characteristics of multilayer monolithic zirconia crowns under occlusal loading, whether composed of uniform or combined yttria levels. The current study investigated how variations in yttria levels and thicknesses affected the optical properties and fracture loads of multilayer monolithic zirconia. Samples of multilayer monolithic zirconia in the Vita A1 shade were used, while employing 3Y (SZ) and 4Y + 5Y (AZ) yttria levels. The optical properties, including the color difference (ΔEWS) and translucency parameters (TP00), were measured using a digital colorimeter. The fracture loads were analyzed using a universal testing machine, and fractured surfaces were examined under a stereomicroscope. Statistical analyses assessed the impacts of the yttria levels and sample thicknesses on the optical properties. The ΔEWS values of SZ ranged 3.6 to 4.0, while for AZ, ΔEWS at 0.5 mm was 3.9 and <2.6 for other thicknesses. The TP00 values decreased with an increased thickness, with AZ generally exhibiting greater translucency than SZ. In the fracture load investigations, SZ (>1600 N) generally exceeded AZ (>1260 N), with fracture loads notably increasing with thickness, particularly for premolars (SZ > 3270 N, AZ > 2257 N). SZ predominantly exhibited partial and complete fractures, whereas AZ showed fewer non-fracture categorizations. Complete fractures began with dense, irregular cracks that extended outward to reveal smooth surfaces, while premolars subjected to higher loads exhibited concentric ripple-like structures. Partial fractures revealed radial textures indicative of areas of stress concentration. In summary, higher yttria levels were correlated with increased translucency, while variations in the fracture loads primarily stemmed from differences in the tooth position or thickness. Overall, multilayer monolithic zirconia incorporating combined yttria levels of 4Y + 5Y (AZ) offered high translucency, precise color matching, and substantial fracture resistance, rendering it highly suitable for aesthetic and functional dental applications.
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Affiliation(s)
- Chien-Ming Kang
- Huayi Dental Laboratory, Taipei 10491, Taiwan
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
| | - Tzu-Yu Peng
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Research Center of Digital Oral Science and Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
| | - Yan-An Wu
- School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
| | - Chi-Fei Hsieh
- School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
| | - Miao-Ching Chi
- Research Center of Digital Oral Science and Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi 61363, Taiwan
- Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chiayi 61363, Taiwan
| | - Hsuan-Yu Wu
- School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Division of Integrated Health Sciences, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima 834-8553, Japan
| | - Zih-Chan Lin
- Research Center of Digital Oral Science and Technology, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan
- Department of Respiratory Care, Chang Gung University of Science and Technology, Chiayi 61363, Taiwan
- Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chiayi 61363, Taiwan
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Li Q, Zhan N, Ng T, Swain MV, Wan B, Jian Y, Wang X, Zhao K. The influence of hygroscopic expansion of resin supporting dies on the fracture resistance of ceramic restorations during thermal cycling. Dent Mater 2024; 40:1231-1243. [PMID: 38853105 DOI: 10.1016/j.dental.2024.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 06/05/2024] [Indexed: 06/11/2024]
Abstract
OBJECTIVES To evaluate the hygroscopic expansion characterization of resin composite dies during thermal cycling, and their influence on the fracture resistance of dental ceramic materials as well as the effect of pre-immersion on these measurements. METHODS Disc-shaped specimens (φ = 15.0 mm, h = 1.2 mm) and anatomical crown dies of four resin composites (epoxy, Z350, P60, G10) were fabricated. Disc-shaped samples were continuously soaked in distilled water and the volume expansion was measured at different time point by Archimedes method. Disc-shaped samples were pre-immersed for 0, 7, or 30 days, elastic modulus and hardness were measured using Nanoindentation test; thermal cycling (TC) test was performed (5 °C-55 °C, 104 cycles), and volume expansion during TC was measured. Four kinds of resin die with pre-immersion for 0, 7, or 30 days were cemented to 5Y-Z crown, or epoxy dies without pre-immersion were cemented to 5Y-Z, 3Y-Z and lithium disilicate glass (LDG) crowns, and load-to-failure testing was performed before and after TC. Finite element analysis (FEA) and fractography analysis were also conducted. RESULTS The hygroscopic expansion was in the order: epoxy > Z350 > P60 > G10. Except for G10, the other three resin composites exhibited different degrees of hygroscopic expansion during TC. Only the elastic modulus and hardness of epoxy decreased after water storage. However, only the fracture loads of 5Y-Z and LDG crowns supported by epoxy dies were significantly decreased after TC. FEA showed a stress concentration at the cervical region of the crown after volume expansion of the die, leading to the increase of the peak stress at the crown during loading. SIGNIFICANCE Only the hygroscopic expansion of epoxy dies caused by TC led to the decrease in the fracture resistance of the 5Y-Z and LDG crown, which may be related to the decrease in the elastic modulus of the epoxy die and the tensile stress caused by it.
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Affiliation(s)
- Qiulan Li
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Ni Zhan
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Takkun Ng
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Michael V Swain
- Don State Technical University, Rostov-on-Don 344000, Russia; AMME, Sydney University, Sydney, Australia
| | - Boyang Wan
- School of Aerospace, Mechanical and Mechatronic Engineering (AMME), The University of Sydney, NSW 2006, Australia
| | - Yutao Jian
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China; Institute of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China.
| | - Xiaodong Wang
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China.
| | - Ke Zhao
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China.
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Li Q, Yang Y, Chen K, Jiang Y, Swain MV, Yao M, He Y, Liang Y, Jian Y, Zhao K. Effect of low-temperature degradation on the fatigue performance of dental strength-gradient multilayered zirconia restorations. J Dent 2024; 142:104866. [PMID: 38281620 DOI: 10.1016/j.jdent.2024.104866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/16/2024] [Accepted: 01/25/2024] [Indexed: 01/30/2024] Open
Abstract
OBJECTIVES Fatigue and low-temperature degradation (LTD) are the main factors contributing to zirconia restoration failure. This study evaluated the effect of LTD on the fatigue performance of the novel "strength & shade-gradient" multilayered zirconia restorations. METHODS Discs (15 mm × 1.2 mm) of each yttria content layer from a newly developed strength-gradient multilayered zirconia were fabricated and under accelerated aging in an autoclave at 134℃ for 0 h, 32 h, and 64 h. Then, the phase transformation, microstructure, and mechanical properties after LTD were assessed. In addition, the crown samples, including the multi-Zir, 3Y-Zir, and 5Y-Zir were fabricated, and their monotonic and fatigue load before and after LTD, percentage of fatigue degradation (Sd) and the fracture morphology were investigated. Statistical analyses were performed using paired samples t-test (α' = α/3 = 0.017), one-way ANOVA and Weibull analysis. RESULTS After LTD, the phase transformation, surface roughness, depth of transformed zone, and residual stress were increased and inversely associated with the yttria content. The indentation elastic modulus and hardness after LTD decreased; however, there was no significant difference between the different yttria content layers. The monotonic and fatigue load of multi-Zir restorations decreased, but their Weibull modulus increased, and Sd decreased, similar to 3Y-Zir. The crack origin was associated with the cervical region. CONCLUSION These results show that although LTD reduces the absolute fatigue strength of strength-gradient multilayered zirconia restorations, it also reduces the effect of cyclic fatigue itself on the strength of zirconia (relative to monotonic strength), which might be due to the increase of residual stress. CLINICAL SIGNIFICANCE The novel "strength & shade-gradient" multilayered zirconia restorations show a promising performance during in vitro LTD and fatigue test and their reliability to some extent is comparable to 3Y-Zir. Yet, further in vivo longitudinal studies are warranted to confirm their precise performance.
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Affiliation(s)
- Qiulan Li
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Yunxu Yang
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Kuangyao Chen
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Yingyu Jiang
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Michael V Swain
- Don State Technical University, Rostov-on-Don 344000, Russia; AMME, Sydney University, Sydney, Australia
| | - Mianfeng Yao
- Xiangya Hospital Central South University, Changsha 410008, China
| | - Ying He
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China
| | - Yujie Liang
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China.
| | - Yutao Jian
- Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China; Institute of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China.
| | - Ke Zhao
- Hospital of Stomatology, Sun Yat-Sen University, Guangzhou 510055, China; Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055, China.
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Mangano FG, Cianci D, Pranno N, Lerner H, Zarone F, Admakin O. Trueness, precision, time-efficiency and cost analysis of chairside additive and subtractive versus lab-based workflows for manufacturing single crowns: An in vitro study. J Dent 2024; 141:104792. [PMID: 38013004 DOI: 10.1016/j.jdent.2023.104792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 11/29/2023] Open
Abstract
PURPOSE To evaluate the trueness, precision, time efficiency, and cost of three different workflows for manufacturing single crowns (SCs). METHODS A plaster model with a prepared tooth (#15) was scanned with an industrial scanner, and an SC was designed in computer-assisted-design (CAD) software. Ten SCs were printed with a hybrid composite (additive chairside) and a stereolithographic (SLA) printer (Dfab®), 10 SCs were milled in lithium disilicate (subtractive chairside) using a chairside milling unit (inLab MC XL®), and 10 SCs were milled in zirconia (lab-based) using a five-axis laboratory machine (DWX-52D®). All SCs were scanned with the same scanner after polymerization/sinterization. Each scan was superimposed to the marginal area of the original CAD file to evaluate trueness: absolute average (ABS AVG), root mean square (RMS), and (90˚-10˚)/2 percentile were calculated for each group. Marginal adaptation and quality of the occlusal and interproximal contact points were also investigated by two prosthodontists on 3D printed and plaster models. Finally, the three workflows' time efficiency and costs were evaluated. RESULTS Additive chairside and subtractive lab-based SCs had significantly better marginal trueness than subtractive chairside SCs in all three parameters (ABS AVG, p < 0.01; RMS, p < 0.01; [90˚-10˚]/2, p < 0.01). However, the two prosthodontists found no significant differences between the three manufacturing procedures in the quality of the marginal closure (p = 0.186), interproximal (p = 0.319), and occlusal contacts (p = 0.218). Both time efficiency and cost show a trend favoring the chairside additive workflow. CONCLUSIONS Chairside additive technology seems to represent a valid alternative for manufacturing definitive SCs, given the high marginal trueness, precision, workflow efficiency and low costs. STATEMENT OF CLINICAL RELEVANCE Additive chairside manufacturing of definitive hybrid composite SCs is now possible and shows high accuracy, time efficiency, and competitive cost.
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Affiliation(s)
- Francesco Guido Mangano
- Department of Pediatric, Preventive Dentistry and Orthodontics, Sechenov First State Medical University, Moscow, Russia.
| | | | - Nicola Pranno
- Department of Oral and Maxillofacial Sciences, Sapienza University, Rome, Italy
| | - Henriette Lerner
- Department of Oral, Maxillofacial and Plastic Surgery, Goethe University, Frankfurt, Germany
| | - Fernando Zarone
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, University Federico II, Naples, Italy
| | - Oleg Admakin
- Department of Pediatric, Preventive Dentistry and Orthodontics, Sechenov First State Medical University, Moscow, Russia
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Sutejo IA, Kim J, Zhang S, Gal CW, Choi YJ, Park H, Yun HS. Fabrication of color-graded feldspathic dental prosthetics for aesthetic and restorative dentistry. Dent Mater 2023:S0109-5641(23)00089-1. [PMID: 37088587 DOI: 10.1016/j.dental.2023.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/22/2023] [Accepted: 03/31/2023] [Indexed: 04/25/2023]
Abstract
OBJECTIVE Feasibility investigation of natural teeth shades replication on dental prosthetics fabricated via functionally graded additive manufacturing (FGAM) using combination of feldspathic porcelain (FP) and yttrium aluminum garnet cerium (Y3Al5O12:Ce, YAG:Ce) as a promising esthetic restoration option. METHODS Color-graded feldspathic crown fabrication parameter through FGAM method was comprehensively examined from the slurry rheology, cure depth, debinding to sintering temperature. Effect of light absorbent also checked towards overcuring reaction during UV exposure by the shape comparison. Lastly, the flexural bending strength measured following ISO 6872:2015 to assure the applicability. Applying the studied parameter, natural teeth shades then imitated and investigated by alteration of FP and FP + 0.1 wt% YAG:Ce (Y-FP). Generated color across the structure captured through mobile camera, interpreted through the CIELAB coordinate and the gradation confirmed by the color differences (ΔE00) calculated using CIEDE2000 formula. RESULT Parameter study indicated that 70 wt% of FP slurry with 3 wt% dispersant and 0.2 wt% light absorbent is favored. It produces excellent flowability in our FGAM system with less overcuring justified by edge margin reduction from 95.65° to 90.00° after UV exposure on rectangle shapes masking. The obtain structure also offers adequate flexural bending strength of 106.26 MPa (FP) and 101.36 MPa (Y-FP) after sintering at 780 °C. This validated the materials as class 2 dental prosthetics citing ISO 6872:2015. Color gradation was verified by the yellow b* value reduction (14.8 to -3.33) as it shifted from cervical to incisal area while ΔE00 further affirmed the differences from each segment in comparison with the FP and Y-FP. SIGNIFICANCE Color gradation was successfully replicated by FP and YAG:Ce composition shift via FGAM technique. This result highlights the potential of FGAM as an alternative for fabricating dental prosthetics with high efficiency and improved esthetic appeal.
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Affiliation(s)
- Imam Akbar Sutejo
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea,; University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Jeehwan Kim
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea,; Pusan National University (PNU), Busan, Republic of Korea
| | - Sinuo Zhang
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea,; University of Science and Technology (UST), Daejeon, Republic of Korea
| | - Chang Woo Gal
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea
| | - Yeong-Jin Choi
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea
| | - Honghyun Park
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea
| | - Hui-Suk Yun
- Korea Institute of Materials Science (KIMS), Changwon, Republic of Korea,; University of Science and Technology (UST), Daejeon, Republic of Korea.
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Strasser T, Wertz M, Koenig A, Koetzsch T, Rosentritt M. Microstructure, composition, and flexural strength of different layers within zirconia materials with strength gradient. Dent Mater 2023; 39:463-468. [PMID: 36907821 DOI: 10.1016/j.dental.2023.03.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 02/01/2023] [Accepted: 03/03/2023] [Indexed: 03/12/2023]
Abstract
OBJECTIVES The aim of this study was to compare composition, microstructure, and mechanical strength of current multilayer zirconia blanks. METHODS Bar shaped specimens were made from several layers of multilayer zirconia blanks (Cercon ht ML, Dentsply Sirona, US; Katana Zirconia YML, Kuraray, J;SHOFU Disk ZR Lucent Supra, Shofu, J; priti multidisc ZrO2 Multi Translucent, Pritidenta, D; IPS e.max ZirCAD Prime, Ivoclar Vivadent, FL). Flexural strength was determined in a three-point bending test on extra-thin bars. X-ray diffraction (XRD) with Rietveld refinement was used to assess crystal structure and scanning electron microscopy (SEM) imaging to visualize the microstructure of each material and layer. RESULTS Mean flexural strength varied between 467.5 ± 97.5 MPa (top layer, IPS e.max ZirCAD Prime) and 898.0 ± 188.5 MPa (bottom layer, Cercon ht ML) with significant (p ≤ 0.055) differences between the individual layers. XRD indicated 5Y-TZP for enamel-layers, 3Y-TZP for dentine-layers, individual mixtures of 3Y-TZP, 4Y-TZP, or 5 Y-TZP for intermediate layers. SEM analysis showed grain sizes between approx. 0.15 and 4 µm. Grain size tended to decrease from top to bottom layers. SIGNIFICANCE The investigated blanks differ predominantly in the intermediate layers. In addition to dimensioning of restorations, the milling position in the blanks must also be taken into account when using multilayer zirconia as restorative material.
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Affiliation(s)
- Thomas Strasser
- Department of Prosthetic Dentistry, University Hospital of Regensburg, 93053 Regensburg, Germany.
| | - Markus Wertz
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Andreas Koenig
- Department of Prosthodontics and Material Sciences, Leipzig University, 04103 Leipzig, Germany
| | - Torsten Koetzsch
- Institute of Mineralogy, Crystallography and Materials Science, Leipzig University, 04275 Leipzig, Germany
| | - Martin Rosentritt
- Department of Prosthetic Dentistry, University Hospital of Regensburg, 93053 Regensburg, Germany
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