Evaluation of setting time and compressive strength of a new bone cement precursor powder containing Mg-Na-Ca

Taking the advantage of a novel magnesium phosphate precursor containing Na and Ca, the cementation rate of the cement, including only Mg/Mg-Na-Ca, was studied. Besides, two effective parameters, that is, calcination temperature, 650 degrees C and 800 degrees C, and powder-to-cement liquid ratio, 1 and 1.5g/mL, were assessed. X-ray diffraction, scanning electron microscopy, ion chromatography, particle size analyser, Vicat needle and compression test were used to characterize the powders and obtained cements. The sample containing Mg-Na-Ca, calcined at 800 degrees C with powder-to-cement liquid ratio of 1.5, obtained the highest compressive strength, 20MPa, but set fast. To control the kinetics of cementation, the powder containing Mg-Na-Ca calcined at 950 degrees C with powder-to-cement liquid ratio of 1.5 and 2g/mL was assessed and the one with 2g/mL set in 9min possessing 22MPa compressive strength was selected as optimal condition to be used as a candidate, injectable bone cement.