Effect of the Calcium to Phosphate Ratio of TTCP on the Properties of a TTCP-DCPD Bone Cement
Elena F. Burguera, F Guitian, Laurence C. Chow
Six different tetracalcium phosphate products were synthesized by solid state reaction at high temperature by varying the overall calcium to phosphate ratio of the synthesis mixture. The objective was to evaluate the effect of the calcium to phosphate ratio on a TTCP-DCPD cement. The resulting six TTCP-DCPD cement mixtures were characterized using X-ray diffraction analysis, scanning electron microscopy and pH measurements. Setting times and compressive strength were also measured. It was found that CaO formed in the TTCP product with a Ca/P ratio of 2.0, which resulted in low strength values (25.61 MPa) when distilled water was used as the setting liquid, even though conversion to hydroxyapatite was not prevented. It was concluded that CaO presence affected the wettability of the cement mixture but not the cement setting reaction. Lower Ca/P ratio products yielded cements with compressive strength values ranging from 46.7 MPa for Ca/P=1.90 to 38.32 MPa for Ca/P=1.85. When a dilute sodium phosphate solution was used as the setting liquid, compressive strength values were 15.3 % lower than those obtained with water as the setting liquid. Setting times ranged from 18 min to 22 min when water was the cement liquid and from 7 min to 8 min when sodium phosphate solution was used, and the calcium to phosphate ratio did not have a marked effect on this property.
, Guitian, F.
and Chow, L.
Effect of the Calcium to Phosphate Ratio of TTCP on the Properties of a TTCP-DCPD Bone Cement, Journal of Biomedical Materials Research Part A, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852684
(Accessed December 4, 2023)