Preparation of α-Tricalcium Phosphate Bone Cement: Effect of Citric Acid

alpha-Tricalcium phosphate (alpha-TCP) is one of the main reactants of the powder phase of several bioactive calcium phosphate bone cements. After preparing TCP, the TCP was determined by the measurement of X-ray diffraction, particle size, and scanning election microscopy. Cements were characterized using viscosity measurements, X-ray diffraction, scanning electron microscopy, and compressive and tensile strengths etc. When citric acid was added is dispersant at different concentration to alpha-tricalcium phosphate bone cements. it was found to act as a fluidizing agent during the first stages of cement mixing. The setting time for cement without citric acid was 300 min, while setting times for cements prepared with 0.5-2.5 M citric acid were at a minimum of 4 min and a maximum of 35 min, respectively. The dissolution-precipitation reaction of alpha-tricalcium phosphate was accelerated by adding citric acid and compressive and diametral tensile strength increased.