Study On A Novel Injectable Vertebral Bone Cement Of Calcium Phosphate And Calcium Sulfate

Objective:To evaluate the characteristics of a novel injectable and degradable vertebral bone cement consisting of different content of calcium phosphate and calcium sulfate dihydrate powers ,and select one suitable mixture in order to satisfy the need of application in vertebra minimally invasive operation .Methods:1. The setting time(initial setting time TI and final setting time TF),setting temperature, compressive strength and injectability was detected by Gillmore bi-pins, infrared rays thermodetector , compressive strength tester, and the method of syringe bolus respectively of calcium phosphate cement (CPC) with varied content of calcium sulfate dihydrate (CSD) (0%, 5%, 10%, 20%, 30%,40%,100%). the degradation in vitro of the samples was investigated by immersing the samples in Tris–HCl solution and the degradation rate of the cement was characterized by its weight loss ratio.Results: In this study, the vertebral filler of CPC with 30%CSD may be satisfy the need of application in vertebra minimally invasive operation on account of the setting time (TI=10.0min,TF=15.3min) , the setting temperature(30.8℃) , the injectability (85.2%) , the compressive strength (20.5MPa). Furthermore, the mixture cement has an excellent degradability in the simulated body fluid in Tris–HCl solution and the degradation rate of the cement was 45.8% by its weight loss ratio at 12th weeks.Conclusion:The mixture of CSD /CPC could develop complementation of each other. The characteristics CPC with 30%CSD may be satisfy the need of application in vertebra minimally invasive operation. Furthermore, the mixture cement has an excellent degradability in the simulated body fluid.