Compliance of an apatitic calcium phosphate cement with the short-term clinical requirements in bone surgery, orthopaedics and dentistry.

An apatitic calcium phosphate cement was developed containing a nucleator in its powder and an accelerator in the liquid and having an initial setting time of 7.5 min and a final setting time of 12.5 min according to testing with Gillmore needles at room temperature. At body temperature the initial setting time is 6 min, after which the wound can be closed. The dough time (during which it can be deformed without damaging its microstructure) is 4 min. Therefore, the time lost during an operation with this material is 2 min. The product does not shrink or expand during setting, neither is there a thermal effect; it does not swell or disintegrate upon exposure to aqueous fluids after initial setting. Upon soaking in Ringer's solution the product obtains a final compressive strength of 40 MPa and 65% of that strength is reached within 6 h at body temperature. Cytotoxicity is absent. Applications are envisaged in bone surgery, orthopaedics and dentistry, a.o. for acceleration of the osseointegration of metal endoprostheses.