Limited compliance of some apatitic calcium phosphate bone cements with clinical requirements

Clinical requirements for calcium phosphate bone cements were formulated in terms of the initial setting time, the final setting time, the cohesion ti me and the ultimate compressive strength. Two cements were tested. Biocemen t H was made of a powder containing alpha-tertiary calcium phosphate and pr ecipitated hydroxyapatite. Biocement F was made of a powder containing, in addition, some monetite. The liquid/powder (L/P) ratio was varied over the range 0.30-0.40 ml g(-1), whereas the accelerator concentration in the liqu id was varied from 0%-4% Na2HPO4 in water. For Biocement H there was no com bination L/P ratio and % Na2HPO4 for which all clincal requirements were sa tisfied. However, Biocement F had a certain area where this was the case. T herefore, it is expected that Biocement F can be applied in clinical situat ions such as orthopaedics, plastic and reconstructive surgery and oral and maxillofacial surgery, even when early contact with blood is inevitable. (C ) 1998 Kluwer Academic Publishers.