Objectives: The aim of the study was to characterize the chemical composition, microstructure and roughness of two commercially available zirconia dental implants (WhiteSky and Zit-Z).
Methods: The chemical composition of the cervical collar and threaded root parts of the implants (n=2) were studied by XPS and HV-EDX. LV-SEM was used for morphological assessment, Raman microanalysis for microstructural characterization and optical profilometry for surface roughness measurements. XRD, HV-EDX and Raman microanalysis of bulk regions (longitudinal sections) were used as reference.
Results: XPS showed the presence of C, O, Zr and Y (collar) plus Al (root) at implant surfaces. More C (10-26at%) and a lower Al/Zr ratio were found in WhiteSky (1.05 vs 1.26 in Zit-Z). Zr, Y and Al were detected in single, fully oxidized states. The same elements, plus Hf, were identified by HV-EDX at bulk and surface regions, with a Al/Zr ratio higher in WhiteSky (0.17 vs 0.09 in Zit-Z). Na, K and Cl contaminants were traced at implant root parts by both methods. XRD analysis of cross-sectioned specimens revealed the presence of monoclinic and tetragonal zirconia along with cubic yttria phases. Raman microanalysis showed that the monoclinic zirconia volume fraction was higher at root surfaces than the collar. No monoclinic phase was found at bulk regions. Significantly higher Sa and Sq values were recorded in WhiteSky than Zit-Z, whereas Zit-Z showed higher Rt value.
Significance: The differences found between the implants in the extent of carbon contamination, residual alumina content, tetragonal to monoclinic ZrO(2) phase transformation and 3D-roughness parameters may contribute to a substantial differentiation in the cellular and tissue response.
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http://dx.doi.org/10.1016/j.dental.2009.11.079 | DOI Listing |
We report lasing action in a femtosecond-laser-inscribed waveguide in thulium-doped barium-gallium-germanium oxide (BGG) glass. A laser cavity was assembled with this waveguide that provided a single-mode output of 62 mW when pumped at 1.6 µm.
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Electrochemistry Department, St. Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia.
In this work, a set of analytical techniques, including scanning electron microscopy (SEM), Raman scattering spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray microanalysis (EDX) and cyclic voltammetry (CV), were used to study the impact of high-energy He ion irradiation on the structural and electrochemical characteristics of sulfur-containing multi-walled carbon nanotubes (S-MWCNTs) placed on a titanium substrate. The results indicate that the ion beam treatment of the S-MWCNT system led to an increase in the level of imperfections on the surface structures of the nanotubes due to the formation of point defects on their outer walls and the appearance of oxygen-containing functional groups, including SO groups, near these defects. At the same time, a significant increase in the sulfur concentration (by 6.
View Article and Find Full Text PDFEnviron Pollut
January 2025
School of Chemistry, Molecular Sciences Institute, University of the Witwatersrand, South Africa; Department of Chemistry, University of Pretoria, Pretoria, South Africa. Electronic address:
This study presents the first comprehensive assessment of microplastics (MPs) in alcoholic (AB) and non-alcohol (NAB) beverages in South Africa. Beverages in various packaging materials, specifically glass, aluminium, and polyethylene terephthalate (PET) were tested for MP content. The samples were filtered and digested, then stained with Rose Bengal dye to facilitate particle identification, followed by physical and chemical characterisation using stereomicroscopy and micro-Raman spectroscopy, respectively.
View Article and Find Full Text PDFJ Environ Radioact
December 2024
Graduate School of Engineering, Hokkaido University, N13W8 Kitaku, Sapporo, 0608628, Japan.
After the Fukushima Daiichi nuclear accident, municipal solid waste (MSW) contaminated with radiocesium was generated. In Japan, approximately 80% of MSW by weight has been incinerated. As consequence, radiocesium was retained in incineration residue after the accident.
View Article and Find Full Text PDFPathologica
August 2024
Research Training Innovation Infrastructure, Research and Innovation Department (DAIRI), Azienda Ospedaliero-Universitaria SS. Antonio e Biagio e Cesare Arrigo, Alessandria, Italy.
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