Abstract:

BACKGROUND: Treatment for osteoporosis and bone defects needs a lot of bone repair materials. Calcium phosphate bone cement, as one of commonly used materials for bone repair, has great brittleness, so clinicians have been looking forward to develop a bone repair material with better biocompatibility and biomechanics.
OBJECTIVE: To evaluate the biocompatibility and in vitro biomechanical properties of a new calcium phosphate bone cement treated by carbon nanotube.
METHODS: In vitro hemolyxzation, cytotoxicity, acute systemic toxicity and hypersensitivity tests were performed on a new calcium phosphate cement according to the requirements given in Biological Standards for Implanted Biomaterials ISO 10993 by International Organization for Standardization. Thoracolumbar vertebral bodies (T12-L4) were harvested from six embalmed cadavers. The flexional compression fractures were experimented. After restoring the height of the vertebral bodies by the percutaneous kyphoplasty, the cement was respectively injected with calcium phosphate cement treated by carbon nanotube and common calcium phosphate cement. The extreme load, compressive strength, stiffness were obtained.
RESULTS AND CONCLUSION: ① The hemolysis rate of the new cement-extracted solution in human was 1.81%, without hemolytic crisis. The cytotoxicity index of the 929 cell was graded as zero. The mouse acute systemic toxicity, mouse inherent toxicity and guinea-pig hypersensitivity were negative in extracting stock solution. ② After vertebroplasty, the extreme load, compressive strength and stiffness of calcium phosphate cement treated by carbon nanotube were significantly higher than those of common calcium phosphate cement. The biocompatibility of the new calcium phosphate cement treated by carbon nanotube is good enough to meet the requirements given in Biological Standards for Implanted Biomaterials by International Organization for Standardization, and the strength and stiffness of the new cement are better than common calcium phosphate cement.