Effects of Setting Liquid on a-calcium Phosphate-Tetracalcium Phosphate Bone Cement

Calcium phosphate cement (CPC) is a kind of promising materials used in dental and orthopeadic restoration. Nowadays, CPC is of special interest due to its self-setting behavior when mixed with an aqueous liquid phase. In this study, alpha-tricalcium phosphate (alpha-TCP) and tetracalcium phosphate (TeCP) were served as the solid component of the cement, and the liquid component was consisted of sodium phosphate dibasic dedocahydrate (SPDD, Na2HPO4 *12H2O), and/or citric acid. The cement's properties as compressive strength and porosity were measured. The effects of preparing conditions, such as liquid-to-powder ratio (L/P) and liquid composition, on compressive strength of calcium phosphate were investigated. The results show that the compressive strength increases with the decreasing of pH value. There is a premium L/P in which the compressive strength gains its maxim. The compressive strength reached 21.69 MPa at the condition of L/P = 0.30mL/g and pH =5.