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 time and the ultimate compressive strength. Two cements were tested. Biocement H was made of a powder containing alpha-tertiary calcium phosphate and precipitated 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 liquid was varied from 0%-4% Na2HPO4 in water. For Biocement H there was no combination L/P ratio and % Na2HPO4 for which all clinical requirements were satisfied. However, Biocement F had a certain area where this was the case. Therefore, it is expected that Biocement F can be applied in clinical situations such as orthopaedics, plastic and reconstructive surgery and oral and maxillofacial surgery, even when early contact with blood is inevitable. Copyright 1998 Kluwer Academic Publishers