Influence of heat treatments upon the mechanical properties and in vitro bioactivity of ZrO2-toughened MgO-CaO-SiO2-P2O5-CaF2 glass-ceramics

• Published in: Biointerphases Vol. 9; no. 3; p. 031014
• Main Authors: Li, Huan-Cai, Wang, Dian-Gang, Meng, Xiang-Guo, Chen, Chuan-Zhong
• Format: Journal Article
• Language: English
• Published: United States 01.09.2014
• Subjects: Apatites - metabolism; Body Fluids - metabolism; Ceramics - radiation effects; Chemical Phenomena; Hot Temperature; Magnesium Oxide - radiation effects; Resin Cements - radiation effects; Zirconium - radiation effects
• ISSN: 1934-8630; 1559-4106
• DOI: 10.1116/1.4892595

Zirconia-toughened MgO-CaO-SiO2-P2O5-CaF2 glass-ceramics are prepared using sintering techniques, and a series of heat treatment procedures are designed to obtain a glass-ceramic with improved properties. The crystallization behavior, phase composition, and morphology of the glass-ceramics are characterized. The bending strength, elastic modulus, fracture toughness, and microhardness of the glass-ceramics are investigated, and the effect mechanism of heat treatments upon the mechanical properties is discussed. The bioactivity of glass-ceramics is then evaluated using the in vitro simulated body fluid (SBF) soaking test, and the mechanism whereby apatite forms on the glass-ceramic surfaces in the SBF solution is discussed. The results indicate that the main crystal phase of the G-24 sample undergoing two heat treatment procedures is Ca5(PO4)3F (fluorapatite), and those of the G-2444 sample undergoing four heat treatment procedures are Ca5(PO4)3F and β-CaSiO3 (β-wollastonite). The heat treatment procedures are found to greatly influence the mechanical properties of the glass-ceramic, and an apatite layer is induced on the glass-ceramic surface after soaking in the SBF solution.