Thin film of biodegradable calcium phosphate coated on threaded commercially pure titanium （ cp- Ti ） dental implants has been investigated as one of alternatives to eliminate the problem of the long- term instabil...Thin film of biodegradable calcium phosphate coated on threaded commercially pure titanium （ cp- Ti ） dental implants has been investigated as one of alternatives to eliminate the problem of the long- term instability of plasma sprayed HA coated implants. In order to compare in-vivo bone-to-implant response behavior among as-machined, HA coated and CMP coated groups, each group was implanted into New Zealand white mature male rabbits for 2 and 6 weeks, and then in-vivo biological behavior was examined in terms of H＆E staining. Initial stability and removable torques of implants were compared among three groups. Measured removable torque of CMP coated specimen at 6 weeks after inplantation was significantly higher than that of non-coated group, but slightly lower than that of HA coated group, without any inflammatory response at the surrounding of the implants. The initial stability （ ISQ value ; implant stability quotient ） of CMP coated specimen at 2 weeks after implantation was slightly lower than that of HA coated group and significantly higher than that of non-coated group. However, after 6 weeks, ISQ value of CMP coated group was slightly higher than that of HA coated group and significantly higher than that of non-coated group.展开更多
Porous hydroxyapatite （HA）-tricalcium phosphate （TCP） ceramic scaffolds were prepared using a screw-type extrusion method with polymer beads. HA and dicalcium phosphate dehydrates （DCPD） were added at various ra...Porous hydroxyapatite （HA）-tricalcium phosphate （TCP） ceramic scaffolds were prepared using a screw-type extrusion method with polymer beads. HA and dicalcium phosphate dehydrates （DCPD） were added at various ratios to obtain different HA/TCP ratios in sintered ceramic scaffolds. To further enhance the pore interconnectivity and porosity, the developed porous ceramic scaffolds were etched with acid solutions. The maximum porosity （- 85%） was observed in the Ca-P scaffold with the lowest HA （-7%） content. On the other hand, the maximum compressive strength was noted in the scaffolds with the highest HA content （ - 85%）. X-ray diffraction showed that the extent of the fl-TCP to a-TCP phase transformation increased with decreasing HA/DCPD ratio. All HCl-etched scaffolds were observed to generate micropores, which improved the interconnectivity, while biomineralization was found to be the same for both the HCl-etched and non- etched scaffolds. In particular, hydrochloric acid etching is a promising method for improving the interconnectivity and porosity of the ceramic scaffolds.展开更多
文摘Thin film of biodegradable calcium phosphate coated on threaded commercially pure titanium （ cp- Ti ） dental implants has been investigated as one of alternatives to eliminate the problem of the long- term instability of plasma sprayed HA coated implants. In order to compare in-vivo bone-to-implant response behavior among as-machined, HA coated and CMP coated groups, each group was implanted into New Zealand white mature male rabbits for 2 and 6 weeks, and then in-vivo biological behavior was examined in terms of H＆E staining. Initial stability and removable torques of implants were compared among three groups. Measured removable torque of CMP coated specimen at 6 weeks after inplantation was significantly higher than that of non-coated group, but slightly lower than that of HA coated group, without any inflammatory response at the surrounding of the implants. The initial stability （ ISQ value ; implant stability quotient ） of CMP coated specimen at 2 weeks after implantation was slightly lower than that of HA coated group and significantly higher than that of non-coated group. However, after 6 weeks, ISQ value of CMP coated group was slightly higher than that of HA coated group and significantly higher than that of non-coated group.
基金supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2012R1A1A4A01014136)
文摘Porous hydroxyapatite （HA）-tricalcium phosphate （TCP） ceramic scaffolds were prepared using a screw-type extrusion method with polymer beads. HA and dicalcium phosphate dehydrates （DCPD） were added at various ratios to obtain different HA/TCP ratios in sintered ceramic scaffolds. To further enhance the pore interconnectivity and porosity, the developed porous ceramic scaffolds were etched with acid solutions. The maximum porosity （- 85%） was observed in the Ca-P scaffold with the lowest HA （-7%） content. On the other hand, the maximum compressive strength was noted in the scaffolds with the highest HA content （ - 85%）. X-ray diffraction showed that the extent of the fl-TCP to a-TCP phase transformation increased with decreasing HA/DCPD ratio. All HCl-etched scaffolds were observed to generate micropores, which improved the interconnectivity, while biomineralization was found to be the same for both the HCl-etched and non- etched scaffolds. In particular, hydrochloric acid etching is a promising method for improving the interconnectivity and porosity of the ceramic scaffolds.
