On the development of an apatitic calcium phosphate bone cement

Development of an apatitic calcium phosphate bone cement is reported. 100 m u Particles of tetracalcium phosphate (TTCP) and dicalcium phosphate dihydr ate (DCPD) were mixed in equimolar ratio to form the cement powder. The wet ting medium used was distilled water with Na2HPO4 as accelerator to manipul ate the setting time. The cement powder, on wetting with the medium, formed a workable putty. The setting times of the putty were measured using a Vic at type apparatus and the compressive strength was determined with a Univer sal Testing Machine. The nature of the precipitated cement was analyzed thr ough X-ray diffraction (XRD), fourier transform infrared spectrometry (FTIR ) and energy dispersive electron microprobe (EDAX). The results shelved the phase to be apatitic with a calcium-to-phosphorous ratio close to that of hydroxyapatite. The microstructure analysis using scanning electron microsc opy (SEM) showed hydroxyapatite nanocrystallite growth over particulate mat rix surface. The structure has an apparent porosity of similar to 52%. Ther e were no appreciable dimensional or thermal changes during setting, The ce ment passed the ill vitro toxicological screening (cytotoxicity and haemoly sis) tests, Optimization of the cement was done by manipulating the acceler ator concentration so that the setting time, hardening time and the compres sive strength had clinically relevant values.