Study on Dental Colored Zirconia Restoration

This paper explored the color and mechanical properties of CeO2 and Er2O3 shaded zirconia ceramics for dental application. Twelve kinds of colored dental ZrO2 powders were prepared. Experimental results showed that the hue of the materials shift from yellow-green to yellow-red with the increasing concentration of the CeO2 and Er2O3, while reducing of the brightness( L* ) value was little. Three-point bending strength decreased form 1209MPa to 845MPa after coloring, which was lower than the uncolored materials (1301MPa). The fracture toughness decrease slightly. SEM observation revealed more porous microstructure in specimen containing both two additives. Cerium oxide and erbium oxide are candidates of color additives for shading dental zirconia ceramics.

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Synthesis of Coloured Dental Zirconia Ceramics and their Mechanical Behaviors

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.594 ◽

2014 ◽

Vol 602-603 ◽

pp. 594-597 ◽

Cited By ~ 1

Author(s):

Jing Li ◽

Shi Ming Liu ◽

Yuan Hua Lin

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Phase Composition ◽

Bending Strength ◽

Linear Shrinkage ◽

Zirconia Ceramic ◽

Mechanical Behaviors ◽

Zirconia Ceramics ◽

Dental Zirconia Ceramics

The effects of Pr6O11 and Er2O3 dopants on microstructure and mechanical properties of zirconia ceramics were investigated. The phase composition and microstructure analysis indicate that samples are all tetragonal phase and grain size is about 50-100 nm. The relative density of zirconia ceramics was above 99.1%, linear shrinkage was nearly 20%, while Vickers hardness was over 12.5 GPa. Three-points bending strength was over 850 MPa which was slightly lower than that of the pure samples, and fracture toughness was above 4.9 MPa*m1/2. The results show that the dopants can be used to obtain the colored zirconia ceramic, and also have effects on its mechanical properties.

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Mechanical Properties and Microstructure of PMMA-ZrO2 Nanocomposites for Dental CAD/CAM

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.533 ◽

2013 ◽

Vol 785-786 ◽

pp. 533-536 ◽

Cited By ~ 4

Author(s):

Shi Bao Li ◽

Yi Min Zhao ◽

Jian Feng Zhang ◽

Cheng Xie ◽

Dong Mei Li ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Bending Strength ◽

In Situ Polymerization ◽

Zirconia Ceramics ◽

Sem Images ◽

The Matrix ◽

Cad Cam ◽

Organic Resin

A novel PMMA-ZrO2 composite (PZC) was prepared by resin infiltrated to ceramic method. The composite mechanical properties were evaluated and correlated to its microstructure. Partially sintered zirconia ceramics (PSZC) were made by isostatic pressing and partially sintering. Subsequently, the PZC was prepared by vacuum infiltrating prepolymerized MMA into PSZC, followed by in-situ polymerization. When PSZC-70% was used as the matrix, the bending strength, elastic modulus, and fracture toughness of the prepared composite i.e PZC-70% were 202.56±12.09 MPa, 58.71±3.98 GPa, and 4.60±0.26 MPa·m1/2, corresponding to 25.69%, 23.31%, and 169.01% improvement, respectively, in comparison with the control matrix. Among them, the fracture toughness improvement was the most prominent. According to SEM images of the fracture surfaces, each pore of zirconia skeleton was filled by organic resin contributing to the bending strength improvement. These weak interfaces between zirconia skeleton and organic resin absorbed energy and terminated the growth of microcracks which might be responsible for significant improvement in fracture toughness. This PZC material is anticipated to be a new member of the dental CAD/CAM family.

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Preparation of Pigmented Glass for Infiltration and Investigation of its Physical and Mechanical Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1802 ◽

2012 ◽

Vol 512-515 ◽

pp. 1802-1806

Author(s):

Huai Xiu Lu ◽

Yuan Fu Yi ◽

Bin Deng ◽

Long Quan Shao ◽

Li Sheng Zhao ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Thermal Expansion ◽

Thermal Properties ◽

Bending Strength ◽

Porous Alumina ◽

Physical And Mechanical Properties ◽

Alumina Crucible ◽

Three Point Bending ◽

Scanning Electron

Aim To explore pigmented glass for infiltration and investigate its physical and mechanical properties. Methods The pigmented glass was prepared by melting glass components in an alumina crucible at 1400°C for 2h. The thermal properties were tested using a Setaram-TGDTA 92 analyzer; three point bending strength and fracture toughness were also tested; the microstructure of the glass was studied using a scanning electron microscope. Results The thermal expansion coefficient over the range 20–600 °C was 6.2 × 10-6 °C -1, Tg was about 690 °C, the density, bending strength, fracture toughness and Vickers hardness were 2.23 g/cm3, 118 MPa, 1.22 MPam1/2, and 7.4 GPa respectively. Conclusion The pigments have no detrimental effects on the physical and mechanical properties; thus the pigmented glass for infiltration has favorable physical and mechanical properties and also good compatibility with presintered porous alumina.

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Mechanical Properties and Microstructure of Partially Sintered Zirconia Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1252 ◽

2008 ◽

Vol 368-372 ◽

pp. 1252-1254 ◽

Cited By ~ 3

Author(s):

Shi Bao Li ◽

Zhao Hui Chen ◽

Yi Min Zhao ◽

Zhong Yi Wang ◽

Li Hui Tang ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Bending Strength ◽

Target Material ◽

Dental Restoration ◽

Diameter Distribution ◽

Zirconia Ceramics ◽

Grain Sizes ◽

Cad Cam

Partially sintered zirconia ceramics (PSZCs) for dental uses were prepared from zirconia nanopowder via isostatic pressing and partially sintering. The open porosities, pore diameters, grain sizes and mechanical properties of the ceramics with different densities were studied. The results show that the pores formed in the PSZCs are all open pores, with a diameter distribution of 60nm~130nm and a grain size distribution of 120~170nm. The machinability becomes worse when the density of PSZC is higher than 75% of the theoretical density, so a ceramic named PSZC-70% with density of 70%TD was selected as the target material. Its bending strength is 168 MPa and fracture toughness is 1.8 MPa·m1/2. A dental restoration framework can be obtained via machining the PSZC-70% on a dental CAD/CAM system.

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Effect of Grain Size on Hardness, Bending Strength and Indentation Toughness of Multi-Doped Zirconia Ceramics

10.20944/preprints201812.0045.v1 ◽

2018 ◽

Author(s):

Y.G. Hoo ◽

Yusheng Shi ◽

Wenzhong Lu

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Size ◽

Size Effect ◽

Bending Strength ◽

Stabilized Zirconia ◽

Zirconia Ceramics ◽

Partially Stabilized Zirconia ◽

Indentation Toughness ◽

Wide Range

Partially stabilized zirconia (PSZ) is a promising material with superior combination properties in a wide range of industries. In this study, the effect of grain size on the mechanical properties such as hardness, bending strength and fracture toughness (named as ‘indentation toughness’ in this study) was investigated. The multi-doped zirconia ceramics were prepared by powder processing and pressure-less sintered following four sintering schedules. The measured mechanical properties results show that the polymorph structure sintered at a higher temperature has a lower bending strength and hardness. But 300% more indentation toughness (30.54 Kg/mm) of samples sintered at 1600 °C +1150 °C relative to others was estimated due to the grain size effect by our suggested equation. By contrast, the fracture toughness was calculated with an existing method. The results showed that similar trends were obtained. It appeared to be a novel method for evaluating the toughness of partially stabilized zirconia ceramics with micron grains based on the size effect.

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Effects of Presintering Temperature and Heating Rate on the Physical and Mechanical Properties of Alumina-Glass-Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.549 ◽

2010 ◽

Vol 105-106 ◽

pp. 549-552

Author(s):

Jie Liu ◽

Long Quan Shao ◽

Yuan Fu Yi ◽

Bin Deng ◽

Wei Wei Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Temperature Rise ◽

Modulus Of Elasticity ◽

Bending Strength ◽

Physical And Mechanical Properties ◽

Glass Composites ◽

Three Point Bending ◽

Lower Temperature ◽

Two Temperature

Objective: To study the effects of presintering temperature and temperature rise speed on the physical and mechanical properties of alumina-glass-composite (AGC). Methods: AGC was prepared respectively under the condition that presintered at 1400°C and 1450°C as well as two kind of temperature rise speed. The properties were measured, including density, thermal expansion coefficient, three-point bending strength, fracture toughness, modulus of elasticity and Vicker’s hardness of AGC. Results: With the increasing of presentering temperature and the temperature rise speed, density of AGC decreased, bending strength, fracture toughness, modulus of elasticity increased markedly. There was no difference between three-point bending strength and fracture toughness of AGC that was made by two temperature rise speed to 1450°C. Bending strength of AGC that was made by lower temperature rise speed to 1400°C was the lowest. The Vicker’s hardness of the 1450°C groups was higher than that of the 1400°C groups. Conclusion: Both presintering temperature and the temperature rise speed can influenced the properties of AGC, but the effect of presintering temperature was the most.

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In Situ Preparation and Mechanical Properties of (ZrB2+ZrC)/Zr3[Al(Si)]4C6 Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.602-603.438 ◽

2014 ◽

Vol 602-603 ◽

pp. 438-442

Author(s):

Lei Yu ◽

Jian Yang ◽

Tai Qiu

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Bending Strength ◽

Coefficient Of Thermal Expansion ◽

Raw Materials ◽

Linear Increase ◽

Fine Grain ◽

Fine Grain Strengthening ◽

Uniform Microstructure

Fully dense (ZrB2+ZrC)/Zr3[Al (Si)]4C6 composites with ZrB2 content varying from 0 to 15 vol.% and fixed ZrC content of 10 vol.% were successfully prepared by in situ hot-pressing in Ar atmosphere using ZrH2, Al, Si, C and B4C as raw materials. With the increase of ZrB2 content, both the bending strength and fracture toughness of the composites increase and then decrease. The synergistic action of ZrB2 and ZrC as reinforcements shows significant strengthening and toughing effect to the Zr3[Al (Si)]4C6 matrix. The composite with 10 vol.% ZrB2 shows the optimal mechanical properties: 516 MPa for bending strength and 6.52 MPa·m1/2 for fracture toughness. With the increase of ZrB2 content, the Vickers hardness of the composites shows a near-linear increase from 15.3 GPa to 16.7 GPa. The strengthening and toughening effect can be ascribed to the unique mechanical properties of ZrB2 and ZrC reinforcements, the differences in coefficient of thermal expansion and modulus between them and Zr3[Al (Si)]4C6 matrix, fine grain strengthening and uniform microstructure derived by the in situ synthesis reaction.

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Novel Baddeleyite-Based Zirconia Ceramics for Biomedical Applications

Nano Hybrids and Composites ◽

10.4028/www.scientific.net/nhc.13.9 ◽

2017 ◽

Vol 13 ◽

pp. 9-14

Author(s):

Alexander I. Tyurin ◽

Andrey O. Zhigachev ◽

Alexey V. Umrikhin ◽

Vyacheslav V. Rodaev ◽

Tatyana S. Pirozhkova

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Tetragonal Phase ◽

Biomedical Applications ◽

Zirconia Ceramics ◽

Engineering Ceramics ◽

Synthesis Conditions ◽

Microstructure And Mechanical Properties ◽

First Time

For the first time nanostructured engineering ceramics were prepared from natural zirconia mineral (baddeleyite) with CaO as a tetragonal phase stabilizer. The effect of synthesis conditions on microstructure and mechanical properties of the baddeleyite-based ceramics is reported, furthermore, the effect of calcia content on hardness and fracture toughness is studied. Optimal calcia concentration and synthesis conditions are found, corresponding hardness and fracture toughness values are 10,8 GPa and 13,3 MPa×m1/2. The reported mechanical properties are comparable to those typically reported for yttria-stabilized engineering zirconia ceramics, prepared from chemically synthesized zirconia.

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Effects of TiN Content on Mechanical Properties and Microstructure of ATN Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.589-590.590 ◽

2013 ◽

Vol 589-590 ◽

pp. 590-593 ◽

Cited By ~ 1

Author(s):

Min Wang ◽

Jun Zhao

Keyword(s):

Mechanical Properties ◽

Mechanical Property ◽

Fracture Toughness ◽

Vickers Hardness ◽

Bending Strength ◽

Sintering Temperature ◽

Ceramic Materials ◽

Hot Press ◽

Hot Press Sintering ◽

Tin Content

In order to investigate the effects of TiN content on Al2O3/TiN ceramic material (ATN), the ATN ceramic materials were prepared of TiN content in 30%, 40%, 50%, 60% in the condition of hot press sintering. The sintering temperature is 1700°C, the sintering press is 32MPa, and the holding time are 5min, 10min, 15min. The effects of TiN content on mechanical properties and microstructure of ATN ceramic materials were investigated by analyzing the bending strength, hardness, fracture toughness. The results show that ATN50 has the best mechanical property, its bending strength is 659.41MPa, vickers hardness is 13.79GPa, fracture toughness is 7.06MPa·m1/2. It is indicated that the TiN content has important effect on microstructure and mechanical properties of ATN ceramic materials.

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