ABSTRACT
Calcium phosphate cement (CPC) is well known for the excellent bioactivity and biocompatibility, however, CPC has been used only for the repair of non-load bearing bone defects due to its brittle nature and low flexural strength. Polymer reinforced CPC has been considered as one of the most effective strategies for mechanical reinforcement. This paper summarizes various kinds of polymers loaded CPC:fiber reinforcement, microsphere reinforcement and dual setting cements. It is aimed to analyze the advantages, disadvantages and principles of the polymers reinforced CPC, and so as to lay a foundation for the further research of improving and manufacturing the CPC with ideal mechanical properties.
Subject(s)
Biocompatible Materials , Bone Cements , Calcium Phosphates , Materials Testing , PolymersABSTRACT
Subject(s)
Animals , Mice , Biomimetics , Calcium , Calcium Phosphates , Chromosome Aberrations , Dentin , Dinucleoside Phosphates , Micronucleus Tests , Odontoblasts , Regeneration , RNA , ToothABSTRACT
Objective To compare the osseo-induction and biodegradation performances of three types of injectable and degradable calcium phosphate cement (CPC) so as to find out a better bone substitute. Methods Three types of injectable and degradable CPC were respectively implanted into the bilateral tibias of 24 New Zealand rabbits: pure CPC (Group A), CPC added with Zinc and Strontiumions (Group B), and CPC with composite rhBMP-2 (Group C) . Their systematic and local reactions in implanted region were closely observed. The degra- dation and osseo-induction performances were compared macroscopically, microscopically and by CT scan to find out the one that could best meet clinical needs. Tissue slices were sampled and photographed four, eight and 16 weeks after operation. Five photographs were selected in each group and at each time points for computer software (Image Pro Plus 5.1) processing to calculate the percentages of bone in the images of postoperative slices. Results In Groups A and B, new bone was found to form slowly and little by little, and the ossification was not synchronous with the material degradation. In Group C, however, new bone was observed to form early and massively, and the os- sification was almost synchronous with the material degradation. In Groups A, B and C, the percentage of bone in the images of postoperative slices was (41.7?16.6)%, (31. 2?12.2)% and (71.7?21.0)% respectively. The bone percentage in CPC with composite rhBMP-2 was significantly higher than that in the other two types of CPC (P＜0.01 ). Conclusion The injectable and degradable CPC with composite rhBMP-2 is more suitable for clinical use, because it can induce early new bone formation and synchronous biodegradation.
ABSTRACT
Objective To explore the clinical effect of the percutaneous vertebroplasty(PVP) and filling auto-solidification calcium phosphate cement(CPC) in treatment of osteoporotic thoracolumbar vertebral fractures. Methods From January, 2004, 26 patients with osteoporotic thoracolumbar vertebral compression fracture (29 vertebral bodies) were treated with intraoperative manipulative reduction, PVP and filling auto-solidification CPC. Results PVP were successfully performed with unilateral or bilateral vertebral pedicles for the 29 vertebrae. The average injection dose of CPC was 4.6 mL. CPC leakage occurred during the procedure in 5 vertebrae of 5 cases. All the patients were followed up for 3 to 8 months (averaging 4.6 months) and experienced complete pain relief. There was no severe complication related to the treatment. Except in 3 patients who lost 15%of the vertebral body height, the anterior height of the injured vertebral body in the other 23 patients recovered averagely to 80%of the normal one. Conclusion PVP with filling auto-solidification CPC is safe and effective in the treatment of osteoporotic thoracolumbar vertebral compression fractures.