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Radiopaque Strontium Fluoroapatite Glass-Ceramics

The controlled precipitation of strontium fluoroapatite crystals was studied in four base glass compositions derived from the SiO(2)–Al(2)O(3)–Y(2)O(3)–SrO–Na(2)O–K(2)O/Rb(2)O/Cs(2)O–P(2)O(5)–F system. The crystal phase formation of these glasses and the main properties of the glass-ceramics, such a...

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Autores principales: Höland, Wolfram, Schweiger, Marcel, Dittmer, Marc, Ritzberger, Christian
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4602200/
https://www.ncbi.nlm.nih.gov/pubmed/26528470
http://dx.doi.org/10.3389/fbioe.2015.00149
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author Höland, Wolfram
Schweiger, Marcel
Dittmer, Marc
Ritzberger, Christian
author_facet Höland, Wolfram
Schweiger, Marcel
Dittmer, Marc
Ritzberger, Christian
author_sort Höland, Wolfram
collection PubMed
description The controlled precipitation of strontium fluoroapatite crystals was studied in four base glass compositions derived from the SiO(2)–Al(2)O(3)–Y(2)O(3)–SrO–Na(2)O–K(2)O/Rb(2)O/Cs(2)O–P(2)O(5)–F system. The crystal phase formation of these glasses and the main properties of the glass-ceramics, such as thermal and optical properties and radiopacity were compared with a fifth, a reference glass-ceramic. The reference glass-ceramic was characterized as Ca-fluoroapatite glass-ceramic. The four strontium fluoroapatite glass-ceramics showed the following crystal phases: (a) Sr(5)(PO(4))(3)F – leucite, KAlSi(2)O(6), (b) Sr(5)(PO(4))(3)F – leucite, KAlSi(2)O(6), and nano-sized NaSrPO(4), (c) Sr(5)(PO(4))(3)F – pollucite, CsAlSi(2)O(6), and nano-sized NaSrPO(4), and (d) Sr(5)(PO(4))(3)F – Rb-leucite, RbAlSi(2)O(6), and nano-sized NaSrPO(4). The proof of crystal phase formation was possible by X-ray diffraction. The microstructures, which were studied using scanning electron microscopy, demonstrated a uniform distribution of the crystals in the glass matrix. The Sr-fluoroapatites were precipitated based on an internal crystallization process, and the crystals demonstrated a needle-like morphology. The study of the crystal growth of needle-like Sr-fluoroapatites gave a clear evidence of an Ostwald ripening mechanism. The formation of leucite, pollucite, and Rb-leucite was based on a surface crystallization mechanism. Therefore, a twofold crystallization mechanism was successfully applied to develop these types of glass-ceramics. The main focus of this study was the controlled development of glass-ceramics exhibiting high radiopacity in comparison to the reference glass-ceramic. This goal could be achieved with all four glass-ceramics with the preferred development of the Sr-fluoroapatite – pollucite-type glass-ceramic. In addition to this main development, it was possible to control the thermal properties. Especially the Rb-leucite containing glass-ceramic showed the highest coefficient of thermal expansion (CTE). These glass-ceramics allow optical properties, especially the translucency and color, to be tailored to the needs of biomaterials for dental applications. The authors conclude that it is possible to use twofold crystallization processes to develop glass-ceramic biomaterials featuring different properties, such as specific radiopacity values, CTEs, and optical characteristics.
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spelling pubmed-46022002015-11-02 Radiopaque Strontium Fluoroapatite Glass-Ceramics Höland, Wolfram Schweiger, Marcel Dittmer, Marc Ritzberger, Christian Front Bioeng Biotechnol Bioengineering and Biotechnology The controlled precipitation of strontium fluoroapatite crystals was studied in four base glass compositions derived from the SiO(2)–Al(2)O(3)–Y(2)O(3)–SrO–Na(2)O–K(2)O/Rb(2)O/Cs(2)O–P(2)O(5)–F system. The crystal phase formation of these glasses and the main properties of the glass-ceramics, such as thermal and optical properties and radiopacity were compared with a fifth, a reference glass-ceramic. The reference glass-ceramic was characterized as Ca-fluoroapatite glass-ceramic. The four strontium fluoroapatite glass-ceramics showed the following crystal phases: (a) Sr(5)(PO(4))(3)F – leucite, KAlSi(2)O(6), (b) Sr(5)(PO(4))(3)F – leucite, KAlSi(2)O(6), and nano-sized NaSrPO(4), (c) Sr(5)(PO(4))(3)F – pollucite, CsAlSi(2)O(6), and nano-sized NaSrPO(4), and (d) Sr(5)(PO(4))(3)F – Rb-leucite, RbAlSi(2)O(6), and nano-sized NaSrPO(4). The proof of crystal phase formation was possible by X-ray diffraction. The microstructures, which were studied using scanning electron microscopy, demonstrated a uniform distribution of the crystals in the glass matrix. The Sr-fluoroapatites were precipitated based on an internal crystallization process, and the crystals demonstrated a needle-like morphology. The study of the crystal growth of needle-like Sr-fluoroapatites gave a clear evidence of an Ostwald ripening mechanism. The formation of leucite, pollucite, and Rb-leucite was based on a surface crystallization mechanism. Therefore, a twofold crystallization mechanism was successfully applied to develop these types of glass-ceramics. The main focus of this study was the controlled development of glass-ceramics exhibiting high radiopacity in comparison to the reference glass-ceramic. This goal could be achieved with all four glass-ceramics with the preferred development of the Sr-fluoroapatite – pollucite-type glass-ceramic. In addition to this main development, it was possible to control the thermal properties. Especially the Rb-leucite containing glass-ceramic showed the highest coefficient of thermal expansion (CTE). These glass-ceramics allow optical properties, especially the translucency and color, to be tailored to the needs of biomaterials for dental applications. The authors conclude that it is possible to use twofold crystallization processes to develop glass-ceramic biomaterials featuring different properties, such as specific radiopacity values, CTEs, and optical characteristics. Frontiers Media S.A. 2015-10-13 /pmc/articles/PMC4602200/ /pubmed/26528470 http://dx.doi.org/10.3389/fbioe.2015.00149 Text en Copyright © 2015 Höland, Schweiger, Dittmer and Ritzberger. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Bioengineering and Biotechnology
Höland, Wolfram
Schweiger, Marcel
Dittmer, Marc
Ritzberger, Christian
Radiopaque Strontium Fluoroapatite Glass-Ceramics
title Radiopaque Strontium Fluoroapatite Glass-Ceramics
title_full Radiopaque Strontium Fluoroapatite Glass-Ceramics
title_fullStr Radiopaque Strontium Fluoroapatite Glass-Ceramics
title_full_unstemmed Radiopaque Strontium Fluoroapatite Glass-Ceramics
title_short Radiopaque Strontium Fluoroapatite Glass-Ceramics
title_sort radiopaque strontium fluoroapatite glass-ceramics
topic Bioengineering and Biotechnology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4602200/
https://www.ncbi.nlm.nih.gov/pubmed/26528470
http://dx.doi.org/10.3389/fbioe.2015.00149
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AT schweigermarcel radiopaquestrontiumfluoroapatiteglassceramics
AT dittmermarc radiopaquestrontiumfluoroapatiteglassceramics
AT ritzbergerchristian radiopaquestrontiumfluoroapatiteglassceramics