Functional gradient hydroxyapatite reinforced polyetheretherketone is one of the most promising or- thopedic implant biomaterials. In this study, functional gradient hydroxyapatite reinforced polyetheretherketone bioc...Functional gradient hydroxyapatite reinforced polyetheretherketone is one of the most promising or- thopedic implant biomaterials. In this study, functional gradient hydroxyapatite reinforced polyetheretherketone biocomposites were prepared by layer-by-layer method with the incorporation of hot press molding technology. Studies on the flexural mechanical properties of the functional gradient biocomposites revealed that the flexural stress-stain behavior of the biocomposites presented linear elastic characteristics. The fracture mechanism of the functional gradient biocomposites was predominated by brittle rupture. Furthermore, both flexural strength and break strain of the functional gradient HA/PEEK biocomposites obviously decreased with the rise of the total HA content. The effect of hydroxyapatite concentration difference between adjacent layers （HCDBAL） on the flexural strength obviously relied on the level of HCDBAL and total HA content in the functional gradient HA/PEEK biocomposites. The higher the total HA content in the functional gradient biocomposites is, the less the influence degree of HCDBAL on the flexural strength is. Moreover, total HA content and HCDBAL played synergistic influence on the flexural modulus of the functional gradient HA/PEEK biocomposites.展开更多
FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test ...FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test machine were utilized to characterize the microstructure,component,mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials.The results indicate that an asymmetrical FeCrAl(f)/HA FGM,consolidating powders prepared by mixing HA with 3%–15%(volume fraction) is successfully prepared.Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply.And counter diffusion takes place to some extent in two phase interfaces.The elemental compositions of the FeCrAl(f)/HA FGM change progressively.Ca and P contents increase gradually with immersion time increasing,and thereafter approach equilibrium.The bone-like apatite layer forms on the materials surface,which possesses benign bioactivity,and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone.展开更多
3D printed polyether-ether-ketone(PEEK)implant has become a popular clinical alternative to implants made of titanium alloy for cranial bone substitutes due to its bone-match properties,however its biological inert hi...3D printed polyether-ether-ketone(PEEK)implant has become a popular clinical alternative to implants made of titanium alloy for cranial bone substitutes due to its bone-match properties,however its biological inert hin-dered the progress of clinical applications of such material.To enhance the tissue integration capability of PEEK implants and promote their long-term stability,cranial implants of gradient porous structures were designed and manufactured via fused filament fabrication(FFF)3D printing technology in both PEEK and PEEK/HA com-posites materials,then functionally evaluation of the implants on the tissue in-growth and the osteointegration mechanisms was conducted via animal tests.The 3D printed PEEK scaffold was found to have 2-5 folds of the compressive strength to those of the natural cranial bone.The in vivo studies verified that the porous PEEK/HA scaffold could effectively induce the bone ingrowth to form a stable biointegration boundary surrounding the host bone tissue after 4 weeks of implantation.Moreover,the PEEK/HA scaffold showed no significant advantages in improving the soft tissue in-growth,only making its distribution more evenly.It is also interestingly to find out that the vertically connective pores throughout the implant did not enhance the tissue binding force even though it did promote the nutrient transportation.In conclusion,the use of PEEK/HA composite material and a well-designed porous structure was proved to be an effective approach to improve the biointegration between the implant and host tissues.展开更多
基金financial support by the National Natural Science Foundation of China(No.51175004)
文摘Functional gradient hydroxyapatite reinforced polyetheretherketone is one of the most promising or- thopedic implant biomaterials. In this study, functional gradient hydroxyapatite reinforced polyetheretherketone biocomposites were prepared by layer-by-layer method with the incorporation of hot press molding technology. Studies on the flexural mechanical properties of the functional gradient biocomposites revealed that the flexural stress-stain behavior of the biocomposites presented linear elastic characteristics. The fracture mechanism of the functional gradient biocomposites was predominated by brittle rupture. Furthermore, both flexural strength and break strain of the functional gradient HA/PEEK biocomposites obviously decreased with the rise of the total HA content. The effect of hydroxyapatite concentration difference between adjacent layers （HCDBAL） on the flexural strength obviously relied on the level of HCDBAL and total HA content in the functional gradient HA/PEEK biocomposites. The higher the total HA content in the functional gradient biocomposites is, the less the influence degree of HCDBAL on the flexural strength is. Moreover, total HA content and HCDBAL played synergistic influence on the flexural modulus of the functional gradient HA/PEEK biocomposites.
基金Project(51274247)supported by the National Natural Science Foundation of ChinaProject(2012BAE06B00)supported by the National High Technology Research and Development Program to China+1 种基金Project(2011QNZT046)supported by the Fundamental Research Funds of Central South Universities of ChinaProject supported by Hunan Postdoctoral Scientific Program,China
文摘FeCrAl(f)/HA biological functionally gradient materials(FGMs) were successfully fabricated by the hot pressing technique.Scanning electron microscope(SEM),energy dispersive spectrometer(EDS) and bending strength test machine were utilized to characterize the microstructure,component,mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials.The results indicate that an asymmetrical FeCrAl(f)/HA FGM,consolidating powders prepared by mixing HA with 3%–15%(volume fraction) is successfully prepared.Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply.And counter diffusion takes place to some extent in two phase interfaces.The elemental compositions of the FeCrAl(f)/HA FGM change progressively.Ca and P contents increase gradually with immersion time increasing,and thereafter approach equilibrium.The bone-like apatite layer forms on the materials surface,which possesses benign bioactivity,and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone.
基金supported by National Natural Science Foundation of China(Grant.Nos.51835010,12202347)Natural Science Basic Research Program of Shaanxi Province of China(Grant.No.2022JQ-378)+1 种基金Fundamental Research Funds for the Central Universities and the Program for Innovation Team of Shaanxi Province of China(Grant.No.2023-CX-TD-17)Natural Science Foundation of Guangdong Province of China(Grant.No.2022A1515012552).
文摘3D printed polyether-ether-ketone(PEEK)implant has become a popular clinical alternative to implants made of titanium alloy for cranial bone substitutes due to its bone-match properties,however its biological inert hin-dered the progress of clinical applications of such material.To enhance the tissue integration capability of PEEK implants and promote their long-term stability,cranial implants of gradient porous structures were designed and manufactured via fused filament fabrication(FFF)3D printing technology in both PEEK and PEEK/HA com-posites materials,then functionally evaluation of the implants on the tissue in-growth and the osteointegration mechanisms was conducted via animal tests.The 3D printed PEEK scaffold was found to have 2-5 folds of the compressive strength to those of the natural cranial bone.The in vivo studies verified that the porous PEEK/HA scaffold could effectively induce the bone ingrowth to form a stable biointegration boundary surrounding the host bone tissue after 4 weeks of implantation.Moreover,the PEEK/HA scaffold showed no significant advantages in improving the soft tissue in-growth,only making its distribution more evenly.It is also interestingly to find out that the vertically connective pores throughout the implant did not enhance the tissue binding force even though it did promote the nutrient transportation.In conclusion,the use of PEEK/HA composite material and a well-designed porous structure was proved to be an effective approach to improve the biointegration between the implant and host tissues.
