AIM: To compare seven commercially available bone graft substitutes(BGS) in terms of these properties and without using any additional biological growth factors.METHODS: Porcine osteoprogenitor cells were loaded on se...AIM: To compare seven commercially available bone graft substitutes(BGS) in terms of these properties and without using any additional biological growth factors.METHODS: Porcine osteoprogenitor cells were loaded on seven commercially available BGS and allowed to proliferate for one week followed by osteogenic induction. Staining for live/dead cells as well as scanning electron microscopy(SEM) was carried out to determine viability and cellular binding. Further outcome measures included alkaline phosphatase(ALP) assays with normalisation for DNA content to quantify osteogenic potential. Negative and positive control experiments were carried out in parallel to validate the results.RESULTS: Live/dead and SEM imaging showed higher viability and attachment with β-tricalcium phosphate(β-TCP) than with other BGS(P < 0.05). The average ALP activity in nmol/mL(normalised value for DNA content in nmol/μg DNA) per sample was 657.58(132.03) for β-TCP, 36.22(unable to normalise) for calcium sulphate, 19.93(11.39) for the Hydroxyapatite/Tricalcium Phosphate composite, 14.79(18.53) for polygraft, 13.98(8.15) for the highly porous β-Tricalcium Phosphate, 5.56(10.0) for polymers, and 3.82(3.8) for Hydroxyapatite.CONCLUSION: Under the above experimental conditions, β-TCP was able to maintain better the viability of osteoprogenitor cells and allow proliferation and differentiation(P < 0.05).展开更多
This manuscript focuses on bone repair/regeneration using tissue engineering strategies, and highlights nanobiotechnology developments leading to novel nanocomposite systems. About 6.5 million fractures occur annually...This manuscript focuses on bone repair/regeneration using tissue engineering strategies, and highlights nanobiotechnology developments leading to novel nanocomposite systems. About 6.5 million fractures occur annually in USA, and about 550,000 of these individual cases required the application of a bone graft. Autogenous and allogenous bone have been most widely used for bone graft based therapies; however, there are significant problems such as donor shortage and risk of infection. Alternatives using synthetic and natural biomaterials have been developed, and some are commercially available for clinical applications requiring bone grafts. However, it remains a great challenge to design an ideal synthetic graft that very closely mimics the bone tissue structurally, and can modulate the desired function in osteoblast and progenitor cell populations. Nanobiomaterials, specifically nanocomposites composed of hydroxyapatite （HA） and/or collagen are extremely promising graft substitutes. The biocomposites can be fabricated to mimic the material composition of native bone tissue, and additionally, when using nano-HA （reduced grain size）, one mimics the structural arrangement of native bone. A good understanding of bone biology and structure is critical to development of bone mimicking graft substitutes. HA and collagen exhibit excellent osteoconductive properties which can further modulate the regenerative/ healing process following fracture injury. Combining with other polymeric biomaterials will reinforce the mechanical properties thus making the novel nano-HA based composites comparable to human bone. We report on recent studies using nanocomposites that have been fabricated as particles and nanofibers for regeneration of segmental bone defects. The research in nanocomposites, highlight a pivotal role in the future development of an ideal orthopaedic implant device, however further significant advancements are necessary to achieve clinical use.展开更多
Bone graft substitutes are widely-studied as alternatives to bone grafts in the clinic. The currently available products are mostly ceramics and polymers. Considerable progress has been made in the study of the biodeg...Bone graft substitutes are widely-studied as alternatives to bone grafts in the clinic. The currently available products are mostly ceramics and polymers. Considerable progress has been made in the study of the biodegradable magnesium alloys, which possess the necessary attributions of a suitable substitute, including an excellent mechanical property. In the present study, a minipig model of a lateral tibial plateau defect was used to evaluate the effectiveness of a magnesium alloy in the repair of a critical-sized defect. The micro-arc oxidation （MAO）-coated ZK60 alloy tablets and medical-grade calcium sulfate pellets were used as the test and control materials, respectively. Bone morphology was monitored by computed tomography after the implantation for 2 and 4 months. It was found that the bone morphology in minipigs following magnesium treatment was similar to that of the normal bone, whereas an abnormal and concave morphology was displayed following the calcium sulfate treatment. The average bone healing rate for the magnesium-treated defects was higher than that of the calcium sulfate-treated defects at the first 4 months following the implantation. Overall, magnesium treatment appeared to calcium sulfate treatment. Thus, the MAO-coated ZK60 al substitute, and further research on its biological activity in improve the defect repair as compared with the oy appears to be a useful biocompatible bone graft vivo is needed.展开更多
基金Supported by Educational grant by Smith and Nephew
文摘AIM: To compare seven commercially available bone graft substitutes(BGS) in terms of these properties and without using any additional biological growth factors.METHODS: Porcine osteoprogenitor cells were loaded on seven commercially available BGS and allowed to proliferate for one week followed by osteogenic induction. Staining for live/dead cells as well as scanning electron microscopy(SEM) was carried out to determine viability and cellular binding. Further outcome measures included alkaline phosphatase(ALP) assays with normalisation for DNA content to quantify osteogenic potential. Negative and positive control experiments were carried out in parallel to validate the results.RESULTS: Live/dead and SEM imaging showed higher viability and attachment with β-tricalcium phosphate(β-TCP) than with other BGS(P < 0.05). The average ALP activity in nmol/mL(normalised value for DNA content in nmol/μg DNA) per sample was 657.58(132.03) for β-TCP, 36.22(unable to normalise) for calcium sulphate, 19.93(11.39) for the Hydroxyapatite/Tricalcium Phosphate composite, 14.79(18.53) for polygraft, 13.98(8.15) for the highly porous β-Tricalcium Phosphate, 5.56(10.0) for polymers, and 3.82(3.8) for Hydroxyapatite.CONCLUSION: Under the above experimental conditions, β-TCP was able to maintain better the viability of osteoprogenitor cells and allow proliferation and differentiation(P < 0.05).
文摘This manuscript focuses on bone repair/regeneration using tissue engineering strategies, and highlights nanobiotechnology developments leading to novel nanocomposite systems. About 6.5 million fractures occur annually in USA, and about 550,000 of these individual cases required the application of a bone graft. Autogenous and allogenous bone have been most widely used for bone graft based therapies; however, there are significant problems such as donor shortage and risk of infection. Alternatives using synthetic and natural biomaterials have been developed, and some are commercially available for clinical applications requiring bone grafts. However, it remains a great challenge to design an ideal synthetic graft that very closely mimics the bone tissue structurally, and can modulate the desired function in osteoblast and progenitor cell populations. Nanobiomaterials, specifically nanocomposites composed of hydroxyapatite （HA） and/or collagen are extremely promising graft substitutes. The biocomposites can be fabricated to mimic the material composition of native bone tissue, and additionally, when using nano-HA （reduced grain size）, one mimics the structural arrangement of native bone. A good understanding of bone biology and structure is critical to development of bone mimicking graft substitutes. HA and collagen exhibit excellent osteoconductive properties which can further modulate the regenerative/ healing process following fracture injury. Combining with other polymeric biomaterials will reinforce the mechanical properties thus making the novel nano-HA based composites comparable to human bone. We report on recent studies using nanocomposites that have been fabricated as particles and nanofibers for regeneration of segmental bone defects. The research in nanocomposites, highlight a pivotal role in the future development of an ideal orthopaedic implant device, however further significant advancements are necessary to achieve clinical use.
基金the financial support of National Basic Research Program of China(973 Program,No.2012CB 619101)the National Natural Science Foundation of China (Nos.30970715 and 81101387)
文摘Bone graft substitutes are widely-studied as alternatives to bone grafts in the clinic. The currently available products are mostly ceramics and polymers. Considerable progress has been made in the study of the biodegradable magnesium alloys, which possess the necessary attributions of a suitable substitute, including an excellent mechanical property. In the present study, a minipig model of a lateral tibial plateau defect was used to evaluate the effectiveness of a magnesium alloy in the repair of a critical-sized defect. The micro-arc oxidation （MAO）-coated ZK60 alloy tablets and medical-grade calcium sulfate pellets were used as the test and control materials, respectively. Bone morphology was monitored by computed tomography after the implantation for 2 and 4 months. It was found that the bone morphology in minipigs following magnesium treatment was similar to that of the normal bone, whereas an abnormal and concave morphology was displayed following the calcium sulfate treatment. The average bone healing rate for the magnesium-treated defects was higher than that of the calcium sulfate-treated defects at the first 4 months following the implantation. Overall, magnesium treatment appeared to calcium sulfate treatment. Thus, the MAO-coated ZK60 al substitute, and further research on its biological activity in improve the defect repair as compared with the oy appears to be a useful biocompatible bone graft vivo is needed.
