In vitro bioactivity and crystallization behavior of bioactive glass in the system SiO2-CaO-Al2O3-P2O5-Na2O-MgO-CaF2
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In this study, bioactivity of glass in the system SiO2-CaO-Al2O3-P2O5-Na2O-MgO-CaF2 was investigated. For this purpose, a glass sample was prepared by the traditional melting method. Crystallization behavior of bioactive glass was also investigated using differential thermal analyses. The Avrami constant of bioactive glass sample calculated according to the Ozawa equation was 3.72 ± 0.4, which indicates bulk crystallization. Using the Matusita-Sakka and the Kissinger equations, activation energy of crystal growth was determined as (394 ± 17) kJ mol−1 and (373 ± 12) kJ mol−1, respectively. These results indicate that the crystallization activation energy data of bioactive glass obtained in this study are accurate and reliable. Bioactivity of the resultant glass sample was analyzed by immersion in simulated body fluid. Scanning electron microscopy, thin film X-ray diffraction, ultraviolet spectroscopy and inductively coupled plasma techniques were used to monitor changes in the glass surface and the simulated body fluid composition. The results revealed that a hydroxyapatite layer was formed on the glass surface after 21 days of immersion in SBF. Formation of the hydroxyapatite layer confirmed the bioactivity of the glass in the system SiO2-CaO-Al2O3-P2O5-Na2O-MgO-CaF2. In addition, physical and mechanical properties of the sample were measured to determine changes in the properties with the immersion time. The results show that bioactive glass maintained its strength during the immersion in a simulated body fluid solution.
Keywordsbioactive glass crystallization kinetics bioactivity hardness porosity
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- Agathopoulos, S., Tulyaganov, D. U., Ventura, J. M. G., Kannan, S., Karakassides, M. A., & Ferreira, J. M. F. (2006) Formation of hydroxyapatite onto glasses of the CaO-MgO-SiO2 system with B2O3, Na2O, CaF2 and P2O5 additives. Biomaterials, 27, 1832–1840. DOI: 10.1016/j.biomaterials.2005.10.033.CrossRefGoogle Scholar
- Hench, L. L., & Andersson, Ö. (1993) Bioactive glasses. n: L. L. Hench & J. Wilson (Eds.), An introduction to bioceramics (Advanced Series in Ceramics, Vol. 1, pp. 41–62). Singapore. Malaysia: World Scientific Publishing Co.Google Scholar
- Kingery, W. D., Bowen, H. K., & Uhlmann, D. R. (1976) Introduction to ceramics (2nd Ed.). New York, NY, USA: Wiley.Google Scholar
- Kissinger, H. E. (1956) Variation of peak temperature with heating rate in differential thermal analysis. Journal of Research of the National Bureau of Standards, 57, 217–221.Google Scholar
- Kokubo, T., Shigematsu, M., Nagashima, Y., Tashiro, M., Nakamura, T., Yamamuro, T., & Higashi, S. (1982) Apatite- and wollastonite-containing glass-ceramics for prosthetic application. Bulletin of the Institute for Chemical Research, 60, 260–268.Google Scholar
- O’Donnell, M. D., Watts, S. J., Law, R. V., & Hill, R. G. (2008) Effect of P2O5 content in two series of soda lime phosphosilicate glasses on structure and properties - Part II: Physical properties. Journal of Non-Crystalline Solids, 354, 3561–3566. DOI: 10.1016/j.jnoncrysol.2008.03.035.CrossRefGoogle Scholar
- Yamamuro, T. (1995). Bioceramics. New York, NY, USA: Elsevier.Google Scholar
- Yilmaz, S., & Gunay, V. (2007) Crystallization kinetics of SiO2-MgO-3CaO-P2O5-Al2O3-ZrO2 glass. Materials Science-Poland, 25, 609–617.Google Scholar