Formation and properties of magnesium–ammonium–phosphate hexahydrate biocements in the Ca–Mg–PO4 system
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Calcium substituted trimagnesium phosphate with the general formula CaxMg(3−x)(PO4)2 (0 < x < 1.5) was synthesized by calcination of powder mixtures with the appropriate stoichiometry and reacted with 3.5 M diammonium hydrogenphosphate solution to form a cementitious matrix of magnesium ammonium phosphate hexahydrate (struvite). The degree of ionic substitution was shown to influence physical cement properties; clinically suitable cement formulations with setting times in the range 5–15 min and compressive strengths of >50 MPa were obtained for x ≤ 0.75 together with a grinding time ≥1 h and a powder to liquid ratio ≥2.5 g/ml. The cement cytocompatibility was investigated by culturing human osteoblast cell line MG63 on cement surfaces demonstrating pronounced cell growth during 13 days cultivation.
The authors would like to acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG Gb1/11-1 and DFG Mu1803/7-1).
- 1.Frayssinet P, Rouquet N, Tourenne F, Fages J, Hardy D, Bonel G. Cell-degradation of calcium–phosphate ceramics. Cells Mater. 1993;3(4):383–94.Google Scholar
- 11.Bohner M. pH variations of a solution after injecting brushite cements. Key Eng Mater. 2000;192–1:813–6.Google Scholar
- 17.ASTM-Standard C266-99. Standard test method for time of setting of hydraulic cement paste by Gilmore needles. West Conshohocken: ASTM International; 2002.Google Scholar
- 21.Clarke SA, Hoskins NL, Jordan GR, Henderson SA, Marsh DR. In vitro testing of advanced JAXTM bone void filler system: species differences in the response of bone marrow stromal cells to β-tricalcium phosphate and carboxymethylcellulose gel. J Mater Sci Mater Med. 2007;18:2283–90.CrossRefGoogle Scholar
- 28.Takahashi T, Yamamoto M, Ioku K, Goto S. Relationship between compressive strength and pore structure of hardened cement pastes. Adv Cem Res. 1997;9:25–30.Google Scholar