In vitro and in vivo study of calcium polyphosphate fiber/calcium phosphate cement/micromorselized bone composite for bone defect repair

The aim of this study was to develop a superior bone engineering material for repair of bone defects. A composite of calcium polyphosphate fiber (CPPF)/calcium phosphate cement (CPC)/micromorselized bone was prepared. A scanning electron microscope was used to observe the structure of the composite and measure its porosity. Seventy-two pieces of the material were placed in phosphate buffer solution and changes in pH were measured over time, and compressive strength was also measured. In vivo experiments were carried out on 72 rabbits divided into six groups: bone implantation with CPPF/CPC/micromorselized bone, CPC/micromorselized bone, micromorselized bone, CPPF/CPC, CPC, respectively; and no implantation (control). The implants were assessed with X-ray film and histologically, and bone density and biomechanical strength were measured. The study period was 12 weeks. The addition of CPPF increased apertures of the composite. The bone defects in the CPPF/CPC/micromorselized group compared with the other groups had significantly higher radiographic grading and significantly greater bone density (p < 0.05) and biomechanical strength (p < 0.05). The new composite improves the speed and quality of bone formation. The addition of CPPF improved the mechanical properties of the scaffold material and created higher porosity. (c) 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater: 100B:11901197 2012.