Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15...Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15 implants of each group of the titanium test buplants were coated with 230 μg porcine, high-purified BMP- 3-precipitute per implant. In each case a BMP- 3-couted and an uncoated control-device were implanted into the femoral part of the putellofemoral joint of the right and left leg of 30 adult giant rabbits. Histomorphological and histomorphometrical we found in both groups with BMP- 3-coated test devices an improved osteointegrution. Stutistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of tony formed bone of the BMP- 3-coated corundum- blasted or hydroxyapathe- coated Ti- 6Al- 4 V test devices compared to the non-couted controls of the same t）pe （p 〈 0.01, t-test for matched samples）. In both implant groups with BMP-couting a synergetic effect was verifiable although the bone ongrowth in the hydroxyaputite coated implants was more extensive than in the corundum blasted implants. Light microscopy demonstrated osteointegrution without connective tissue membrane around the surface of the implants. Our results indicate that composite metal implants,as used in endoprosthetics and implantology , are suitable carriers for BMP- 3 and im proved fixation of the implants can be achieved. The hydroxyapatite surface is superior to the corundum-blasted surface with regards to the observed parameters because of its pronounced bioactivity and its osteoconductive characteristics.展开更多
In the field of tissue engineering,there is significant subsidence of the porous design scaffold several months after implantation.To avoid stress shielding and stimulate bone and cartilage ingrowth,high scaffold poro...In the field of tissue engineering,there is significant subsidence of the porous design scaffold several months after implantation.To avoid stress shielding and stimulate bone and cartilage ingrowth,high scaffold porosity is needed to diminish the mechanical properties of the scaffold.The closer the mechanical properties of the scaffold are to those of surrounding tissues,the better biological properties it will get.Besides,adequate mechanical stability is needed as the scaffold needs to be well fixed in the target area and it will endure load after surgery.Evaluating the mechanical fixation of the scaffold at the initial stage and the long-term performance of a scaffold for in vivo study is hard,as no facility can be put into the target area for the friction test.This study investigated the mechanical stability of the biomimetic scaffold at the initial stage of implantation by finite element analysis(FEA).According to in vivo study,scaffold could not maintain its original position and would sink 1-2 mm in the target area.The simulation results suggested that mechanical loading is not the main reason for scaffold subsidence.展开更多
文摘Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15 implants of each group of the titanium test buplants were coated with 230 μg porcine, high-purified BMP- 3-precipitute per implant. In each case a BMP- 3-couted and an uncoated control-device were implanted into the femoral part of the putellofemoral joint of the right and left leg of 30 adult giant rabbits. Histomorphological and histomorphometrical we found in both groups with BMP- 3-coated test devices an improved osteointegrution. Stutistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of tony formed bone of the BMP- 3-coated corundum- blasted or hydroxyapathe- coated Ti- 6Al- 4 V test devices compared to the non-couted controls of the same t）pe （p 〈 0.01, t-test for matched samples）. In both implant groups with BMP-couting a synergetic effect was verifiable although the bone ongrowth in the hydroxyaputite coated implants was more extensive than in the corundum blasted implants. Light microscopy demonstrated osteointegrution without connective tissue membrane around the surface of the implants. Our results indicate that composite metal implants,as used in endoprosthetics and implantology , are suitable carriers for BMP- 3 and im proved fixation of the implants can be achieved. The hydroxyapatite surface is superior to the corundum-blasted surface with regards to the observed parameters because of its pronounced bioactivity and its osteoconductive characteristics.
基金financially supported by Versus Arthritis Research UK (No.21977)European Commission via a H2020-MSCA-RISE Programme (BAMOS,No.734156)+2 种基金Innovative UK via Newton Fund (No.102872)Engineering and Physical Science Research Council (EPSRC) via DTP CASE Programme (No.EP/T517793/1)the Intergovernmental Cooperation in Science and Technology of China (No.2016YFE0125300)
文摘In the field of tissue engineering,there is significant subsidence of the porous design scaffold several months after implantation.To avoid stress shielding and stimulate bone and cartilage ingrowth,high scaffold porosity is needed to diminish the mechanical properties of the scaffold.The closer the mechanical properties of the scaffold are to those of surrounding tissues,the better biological properties it will get.Besides,adequate mechanical stability is needed as the scaffold needs to be well fixed in the target area and it will endure load after surgery.Evaluating the mechanical fixation of the scaffold at the initial stage and the long-term performance of a scaffold for in vivo study is hard,as no facility can be put into the target area for the friction test.This study investigated the mechanical stability of the biomimetic scaffold at the initial stage of implantation by finite element analysis(FEA).According to in vivo study,scaffold could not maintain its original position and would sink 1-2 mm in the target area.The simulation results suggested that mechanical loading is not the main reason for scaffold subsidence.
