Papers by Author: Qiang Cheng

Abstract: Calcium polyphosphate (CPP) bioceramics with different Ca/P ratios were fabricated. It was shown that the contents of CPP in the sintered ceramics decrease with the increasing Ca/P ratios (0.5-1.0) of the precursors. The higher the Ca/P ratios of precursors were, the more complex the phases of polymerization were. The compressive strengths of ceramics sintered at the same temperature showed a linear decreasing tendency with the increasing Ca/P ratio.

Abstract: Calcium sulphate hemihydrate/α-tricalcium phosphate (CSH-TCP) cement are promising bone replacement materials with controllable-degradation rate and setting time and excellent delivery matrix for sustained release. In the present study, setting behaviors of binary bone cement composed of α-TCP and CSH and release of ciprofloxacin from this cement were investigated in vitro. XRD and SEM results demonstrated that the setting products of CSH-TCP cement were calcium sulphate dihydrate with pillar morphology and hydroxyapatite with needle morphology. Only 20% ciprofloxacin was released from CSH-TCP cement in 7 days in vitro. Fibers of hydroxyapatite enhanced strength of binary cement through fiber-reinforce mechanism. At initial stage (less than 100 hours), the release of ciprofloxacin from CSH-TCP cement was diffusion control, and at subsequent stage the release was matrix dissolution & diffusion control.