Experiment On Fractures Of Tibia Plateau Of Dog Agglutinated With Magnesium Phosphate Cement

Objectives: To investigate the adhesive capacity and adhesive strength , the degradation and the absorption rate ,to study the mechanism of agglutination and absorption and to observe the effect on the fracture healing process, of Magnesium phosphate cement(MPC) in tibial plateau fracture model of dogs in vivo.Methods: There were 38 healthy dogs. The one side tibial plateau fracture model of each dog was made by open osteotomy, fractures agglutinated with MPC. After operation,the effect of fractures agglutination and the degradation of absorption was investigated by general observation, pathology, radiography,and adhersive strength of bone-MPC agglutinated body was examed at different times.Results: 3 days, 3 weeks, 6 weeks and 9 weeks postoperatively,the results of general observation and histological examination showed that bone fractures can be adhesived tightly by MPC, with rarely fixed bone displacement and separation, and the close speed of the fracture healing with the degradation of absorption. 3,6,9,12 weeks postoperatively,fractures were fixed tightly in X-ray so that there were no displacement and separation. We observed the fracture line, through the trabecular bone, the fuzzy fracture line and complete healing gradually. Examination of biomechanical strength of tension 3 days and 3 weeks, 6 weeks postoperatively in vitro, show that the strength of tension of 3 days was lowest. The strength of tension was increasing gradually with the running time, 6 weeks postoperatively achieving the highest value, and 9 weeks, 12 weeks postoperatively were at the same level.Conclusion: 1. MPC can be used to agglutinate the tibial plateau fractures of dogs.2. MPC has some bone agglutination strength to be a material adhesiving fractures. 3. MPC can be biodegradable ,absorped, safe, non-toxic, and biocompatible.