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Biomedical Glasses

Editor-in-Chief: Boccaccini, Aldo R.

CiteScore 2018: 2.05

SCImago Journal Rank (SJR) 2018: 0.424
Source Normalized Impact per Paper (SNIP) 2018: 0.562

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Insight into the atomic scale structure of CaF2-CaO-SiO2 glasses using a combination of neutron diffraction, 29Si solid state NMR, high energy X-ray diffraction, FTIR, and XPS

Louis Forto Chungong
  • Aston Institute of Materials Research, School of Engineering & Applied Science, Aston University, Birmingham B4 7ET, United Kingdom
  • Other articles by this author:
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/ Mark A. Isaacs
  • Aston Institute of Materials Research, School of Engineering & Applied Science, Aston University, Birmingham B4 7ET, United Kingdom; Department of Chemistry, University College London, London, WC1H 0AJ, United Kingdom; Harwell XPS, Research Complex at Harwell, Rutherford Appleton Laboratories, Didcot, OX11 0FA, United Kingdom
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/ Alexander P. Morrell
  • Aston Institute of Materials Research, School of Engineering & Applied Science, Aston University, Birmingham B4 7ET, United Kingdom
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/ Laura A. Swansbury / Alex C. Hannon
  • ISIS facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0QX, United Kingdom
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/ Adam F. Lee
  • Applied Chemistry & Environmental Science, School of Science, RMIT University, Melbourne VIC 3000, Australia
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/ Gavin Mountjoy / Richard A. Martin
  • Corresponding author
  • Aston Institute of Materials Research, School of Engineering & Applied Science, Aston University, Birmingham B4 7ET, United Kingdom
  • Email
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Published Online: 2019-12-05 | DOI: https://doi.org/10.1515/bglass-2019-0010


Bioactive glasses are important for biomedical and dental applications. The controlled release of key ions, which elicit favourable biological responses, is known to be the first key step in the bioactivity of these materials. Properties such as bioactivity and solubility can be tailored for specific applications. The addition of fluoride ions is particularly interesting for dental applications as it promotes the formation of fluoro-apatite. To date there have been mixed reports in the literature on how fluorine is structurally incorporated into bioactive glasses. To optimize the design and subsequent bioactivity of these glasses, it is important to understand the connections between the glass composition, structure and relevant macroscopic properties such as apatite formation and glass degradation in aqueous media. Using neutron diffraction, high energy X-ray diffraction, 29Si NMR, FTIR and XPS we have investigated the atomic scale structure of mixed calcium oxide / calcium fluoride silicate based bioactive glasses. No evidence of direct Si-F bonding was observed, instead fluorine was found to bond directly to calcium resulting in mixed oxygen/fluoride polyhedra. It was therefore concluded that the addition of fluorine does not depolymerise the silicate network and that the widely used network connectivity models are valid in these oxyfluoride systems.

Keywords: Bioactive glass; fluoride; structure; network connectivity


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About the article

Received: 2019-08-12

Revised: 2019-10-17

Accepted: 2019-11-03

Published Online: 2019-12-05

Citation Information: Biomedical Glasses, Volume 5, Issue 1, Pages 112–123, ISSN (Online) 2299-3932, DOI: https://doi.org/10.1515/bglass-2019-0010.

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© 2019 Louis Forto Chungong et al., published by De Gruyter. This work is licensed under the Creative Commons Attribution 4.0 Public License. BY 4.0

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