IN-VIVO SETTING BEHAVIOR OF FAST-SETTING CALCIUM-PHOSPHATE CEMENT

The in vivo setting behaviour of fast-setting calcium phosphate cement (FSCPC) between femoral muscles of the rat was investigated to evalua te the possible value of FSCPC for medical and dental application. Con ventional CPC (c-CPC) and FSCPC were implanted between femoral muscles , and various aspects of the setting behaviour such as setting time, m echanical strength and conversion ratio of cement into hydroxyapatite (HAP: Ca-10(PO4)(6)(OH)(2)) were measured by the Vicat needle method, diametral tensile strength (DTS) measurement, and quantitative powder X-ray diffraction (XRD) analysis, respectively. The setting time of FS CPC in vivo was 5-7 min, in contrast to 48 min for c-CPC. As a result of its fast setting, set specimens of FSCPC showed higher mechanical s trength from the initial stage than c-GPC. Higher DTS values were obse rved in FSCPC than c-CPC implanted after 24 h. Powder XRD analysis rev ealed faster conversion of FSCPC than c-CPC into HAP, which was respon sible both for the faster setting and higher mechanical strength from the initial stage. We concluded, therefore, that FSCPC may be used for a wide range of clinical applications, i.e. fields where fast setting is required such as orthopaedic, plastic and reconstructive, and oral and maxillofacial surgery.