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Good Biocompatibility and Sintering Properties of Zirconia Nanoparticles Synthesized via Vapor-phase Hydrolysis.

ABSTRACT: ZrO2 nanoparticles were synthesized by a vapor-phase hydrolysis process, and characterized in terms of crystalline structures, hardness and microstructures by X-ray diffraction, Vickers hardness test method, and atomic force microscopy (AFM) measurements. Moreover, in vitro cytotoxicity evaluation and hemolysis assay showed that the nanoparticles possessed good biocompatibility. Hardness investigations and AFM measurements indicated that both the sintering temperature and compression force played an important role in determining the physical behaviors (hardness, roughness and density) of flakes of the ZrO2 nanoparticles. When ZrO2 nanoparticles synthesized at 500?°C were pressed into flakes under 6?MPa and sintered at 1400?°C, the resulting flakes exhibited an optimal combination of hardness (534.58?gf·mm-2), roughness (0.07??m) and density (4.41?g·cm-3). As the Vickers hardness value of human bones is of 315~535?gf·mm-2 and the density of adult femuris about 1.3~1.7?g·cm-3, the experimental results showed that the ZrO2 flakes were comparable to human bones with a higher density. As a result, the synthesized ZrO2 NPs may be useful for biomedical applications, especially for bone repair and replacement in future.

SUBMITTER: Wang J

PROVIDER: S-EPMC5057113 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Good Biocompatibility and Sintering Properties of Zirconia Nanoparticles Synthesized via Vapor-phase Hydrolysis.

Wang Jigang J Yin Wenyan W He Xiao X Wang Qiang Q Guo Ming M Chen Shaowei S

Scientific reports 20161011

ZrO<sub>2</sub> nanoparticles were synthesized by a vapor-phase hydrolysis process, and characterized in terms of crystalline structures, hardness and microstructures by X-ray diffraction, Vickers hardness test method, and atomic force microscopy (AFM) measurements. Moreover, in vitro cytotoxicity evaluation and hemolysis assay showed that the nanoparticles possessed good biocompatibility. Hardness investigations and AFM measurements indicated that both the sintering temperature and compression ...[more]

PMID: 27725744

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Project description:BackgroundTo explore the effect of adhesive surface with porcelain sintering and different silane coupling agents on adhesive properties of zirconia ceramics.MethodsZirconia blocks (n=72) were randomly divided into two large groups (n=36) according to whether the adhesive surface was treated with sintered porcelain: N (no porcelain sintering), P (porcelain sintering). Then, according to different silane coupling agents, each group was randomly divided into three small groups, six small groups in total (n=12): NN (no porcelain sintering and agent), NM (no porcelain sintering + Monobond-S), NC (no porcelain sintering + Clearfil Repair); PN (porcelain sintering + no agent), PM (porcelain sintering + Monobond-S), PC (porcelain sintering + Clearfil Repair). After surface treatment, RelyX Unicem Cement was used to make ceramic-resin bonding specimens. Then, each of the six small groups was randomly divided into two subgroups; shear bond strength (SBS) was tested and bond failure mode was analyzed before and after thermal cycling 5,000 times.Results(I) SBS analysis: the SBS values of the P groups were significantly higher than those of the N groups (P<0.05). The groups treated with silane coupling agents showed higher SBS values than the control group (P<0.05), and the PC groups showed the highest SBS values (P<0.05). The SBS of each group was significantly decreased after thermal cycling (P<0.05). (II) The microcharacteristics under scanning electron microscopy and energy spectrum analysis: the ceramic blocks being treated by porcelain sintering showed more roughness than the control group. A large amount of silicon (Si) appeared on the surface of the ceramic blocks after porcelain sintering.Conclusions(I) Treating the adhesive surface by porcelain sintering can improve the bonding strength between zirconia and RelyX Unicem Cement, and the effect was better in conjunction with silane coupling agent. (II) The two kinds of silane coupling agent (Monobond-S, Clearfil Repair) can improve the bonding strength between zirconia and resin cement. The effect of Clearfil Repair is better than that of Monobond-S. (III) Thermal cycling had a significant adverse effect on SBS between zirconia and RelyX Unicem Cement. Clearfil Repair is helpful in improving the durability of zirconia bonding strength.

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Good Biocompatibility and Sintering Properties of Zirconia Nanoparticles Synthesized via Vapor-phase Hydrolysis.

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Good Biocompatibility and Sintering Properties of Zirconia Nanoparticles Synthesized via Vapor-phase Hydrolysis.

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