In this paper,a silvered gradient nanostructured(GNS)layer was successfully fabricated on Ti6Al4V surface by means of surface ultrasonic rolling treatment(SURT)combined with silvering process.Surface characteristics,m...In this paper,a silvered gradient nanostructured(GNS)layer was successfully fabricated on Ti6Al4V surface by means of surface ultrasonic rolling treatment(SURT)combined with silvering process.Surface characteristics,mechanical properties,corrosion resistance,antibacterial ability and cytotoxicity of GNS Ag/Ti6Al4V were investigated in comparison with those of coarse-grained(CG)and GNS Ti6Al4V samples.Owing to the greatly enhanced diffusion kinetics of Ag in the GNS layer,surface silvering on GNS Ti6Al4V was achieved at a relatively low temperature(500℃),and the release rate of Ag^(+)was substantially accelerated,which endowed GNS Ag/Ti6Al4V with excellent antibacterial property.Moreover,improved wear and corrosion resistance of GNS Ag/Ti6Al4V can be achieved without cytotoxicity,indicating excellent bioadaptability.展开更多
Biocompatibility is the basic requirement of biomaterials for tissue repair. However, the present concept of biocompatibility has a certain limitation in explaining the phenomena involved in biomaterial-based tissue r...Biocompatibility is the basic requirement of biomaterials for tissue repair. However, the present concept of biocompatibility has a certain limitation in explaining the phenomena involved in biomaterial-based tissue repair. New materials, in particular those for tissue engineering and regeneration, have been developed with common characteristics, i.e. they participate deeply into important chemical and biological processes in the human body and the interaction between the biomaterials and tissues is far more complex. Understanding the interplay between these biomaterials and tissues is vital for their development and functionalization. Herein, we suggest the concept of bioadaptability of biomaterials. This concept describes the three most important aspects that can determine the performance of biomaterials in tissue repair： 1） the adaptability of the micro-environment created by biomaterials to the native microenvironment in situ; 2） the adaptability of the mechanical properties of biomaterials to the native tissue; 3） the adaptability of the degradation properties of biomaterials to the new tissue formation. The concept of bioadaptability emphasizes both the material＇s characteristics and biological aspects within a certain micro-environment and molecular mechanism. It may provide new inspiration to uncover the interaction mechanism of biomaterials and tissues, to foster the new ideas of functionalization of biomaterials and to investigate the fundamental issues during the tissue repair process by biomaterials. Furthermore, designing biomaterials with such bioadaptability would open a new door for repairing and regenerating organs or tissues. In this review, we summarized the works in recent years on the bioadaptability of biomaterials for tissue repair applications.展开更多
The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recap...The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recapitulate the targeted tissue with spatiotemporal precision and hierarchical accuracy,ranging from atoms and molecules(genes,proteins,etc.)to cells(including organelles)and to tissues and organs.In comparison to traditional bio-inert metallic bone implants such as Co-based alloys and Ti alloys,biodegradable metal(Mg and Zn alloys)bone implants had been developed and might arise many unexpected variables in the bone repair,due to their bioactive nature.In this paper,the bone repair without and with the presence of metallic implants is compared.Thereafter,the perspectives concerning the interactions between the bone tissues and biodegradable metal implants are put forward,and how to better mimic in vivo biodegradation by in vitro experiments is proposed for further research and development of biodegradable metals.展开更多
A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularizat...A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularization and bone regeneration.The angio-conductive properties and concurrent osteogenesis of the highly interconnected porousβ-TCP scaffold were revealed and quantified through an in vivo model that simulated the ischemic environment of ANFH.Mechanical test and finite element analysis showed that the mechanical loss caused by tissue necrosis and surgery was immediately partially compensated after implantation,and the strength of the operated femoral head was adaptively increased and eventually returned to normal bone,along with continuous material degradation and bone regeneration.For translational application,we further conducted a multi-center open-label clinical trial to assess the efficacy of theβ-TCP system in treating ANFH.Two hundred fourteen patients with 246 hips were enrolled for evaluation,and 82.1%of the operated hips survived at a 42.79-month median follow-up.The imaging results,hip function,and pain scores were dramatically improved compared to preoperative levels.ARCO stage II disease outperformed stage III in terms of clinical effectiveness.Thus,bio-adaptive reconstruction using theβ-TCP system is a promising hip-preserving strategy for the treatment of ANFH.展开更多
Magnesium （Mg） has been widely accepted as osteoconductive biomaterial, but osseointegration of Mg device at different implantation sites is still unclear. In the present study, high-purity magnesium （HP Mg） pins ...Magnesium （Mg） has been widely accepted as osteoconductive biomaterial, but osseointegration of Mg device at different implantation sites is still unclear. In the present study, high-purity magnesium （HP Mg） pins were implanted into femoral shaft and condyle of New Zealand rabbits concurrently. 2, 8, 12 and 16 weeks after surgery, rabbit femurs were harvested for micro-computed tomography （micro-CT） scanning and subsequent histological examinations. HP Mg pins were retrieved for scanning electron microscope and energy dispersive spectrum （SEM/EDS） analyses. HP Mg pins at both implantation sites performed stable corrosion with mineral deposition and bone incorporation on surface. However, difference in distribution of contact osteogenesis centers and biological properties of peri-implant bone tissues was detected between femoral shaft and femoral condyle. In femoral condyle, contact osteogenesis centers originated from both periosteum and cancellous bones and the whole HP Mg pin was encapsuled in trabecular bone at 16 weeks. Meanwhile, bone volume to total bone volume （BV/TV） and bone mineral density （BMD） of peri-implant bone tissues were above those of normal bone tissues. In femoral shaft, contact osteogenesis centers were only from periosteum and direct bone contact was confined in cortical bone, while BV/TV and BMD kept lower than normal. Furthermore, new formation of peri-implant bone tissues was more active in femoral condyle than in femoral shaft at 16 weeks. Therefore, although HP Mg performed good biocompatibility and corrosion behavior in vivo, its bioadaption of osseointegration at different implantations sites should be taken into consideration. Bone metaphysic was suitable for Mg devices where peri-implant bone tissues regenerated rapidly and the biological properties were close to normal bone tissues.展开更多
In this work, porous Ti6Al4V alloys with 30%-70% porosity for biomedical applications were fabricated by diffusion bonding of alloy meshes. Pore structure was characterized by Micro-CT and SEM. Compressive behavior in...In this work, porous Ti6Al4V alloys with 30%-70% porosity for biomedical applications were fabricated by diffusion bonding of alloy meshes. Pore structure was characterized by Micro-CT and SEM. Compressive behavior in the out-of-plane direction and biocompatibility with cortical bone were studied. The results reveal that the fabricated porous Ti6Al4V alloys possess anisotropic structure with square pores in the in-plane direction and elongated pores in the out-of-plane direction. The average pore size of porous Ti6Al4V alloys with 30%-70% porosity is in the range of 240-360 Bin. By tailoring diffusion bonding temperature, aspect ratio of alloy meshes and porosity, porous Ti6Al4V alloys with different compressive properties can be obtained, for instance, Young＇s modulus and yield stress in the ranges of 4-40 GPa and 70-500 MPa, respectively. Yield stress of porous Ti6Al4V alloys fabricated by diffusion bonding is close to that of alloys fabricated by rapid prototyping, hut higher than that of fabricated by powder sintering and space-holder method. Diffusion bonding temperature has some effects on the yield stress of porous Ti6Al4V alloys, but has a minor effect on the Young＇s modulus. The relationship between compressive properties and relative density conforms well to the Gibson-Ashby model. The Young＇s modulus is linear with the aspect ratio, while the yield stress is linear with the square of aspect ratio of alloy meshes. Porous Ti6Al4V alloys with 60%-70% porosity have potential for cortical bone implant applications.展开更多
Tissue repair is always a complex process and artificial biomaterials have never been perfect. For example, the mismatch of mechanical property between biomaterials and the host can result in stress shielding; the asy...Tissue repair is always a complex process and artificial biomaterials have never been perfect. For example, the mismatch of mechanical property between biomaterials and the host can result in stress shielding; the asynchronous biodegradation rate of biomaterials and tissue regeneration may extend the repair time.展开更多
Biomaterials are increasingly being evolved to actively adapt to the desired microenvironments so as to introduce tissue integration, reconstruct stability, promote regeneration, and avoid immune rejection. The comple...Biomaterials are increasingly being evolved to actively adapt to the desired microenvironments so as to introduce tissue integration, reconstruct stability, promote regeneration, and avoid immune rejection. The complexity of its mechanisms poses great challenge to current biomimetic synthetic materials. Although still at initial stage, harnessing cells, tissues, or even entire body to synthesize bioadaptive materials is introducing a promising future.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51801064,51961012 and 52001122)Jiangxi Outstanding Young Talents Program(No.20192BCB23014)Jiangxi Key Research and Development Program(No.20203BBE53050).
文摘In this paper,a silvered gradient nanostructured(GNS)layer was successfully fabricated on Ti6Al4V surface by means of surface ultrasonic rolling treatment(SURT)combined with silvering process.Surface characteristics,mechanical properties,corrosion resistance,antibacterial ability and cytotoxicity of GNS Ag/Ti6Al4V were investigated in comparison with those of coarse-grained(CG)and GNS Ti6Al4V samples.Owing to the greatly enhanced diffusion kinetics of Ag in the GNS layer,surface silvering on GNS Ti6Al4V was achieved at a relatively low temperature(500℃),and the release rate of Ag^(+)was substantially accelerated,which endowed GNS Ag/Ti6Al4V with excellent antibacterial property.Moreover,improved wear and corrosion resistance of GNS Ag/Ti6Al4V can be achieved without cytotoxicity,indicating excellent bioadaptability.
基金supported by the National Basic Research Program of China(No.2012CB619100)
文摘Biocompatibility is the basic requirement of biomaterials for tissue repair. However, the present concept of biocompatibility has a certain limitation in explaining the phenomena involved in biomaterial-based tissue repair. New materials, in particular those for tissue engineering and regeneration, have been developed with common characteristics, i.e. they participate deeply into important chemical and biological processes in the human body and the interaction between the biomaterials and tissues is far more complex. Understanding the interplay between these biomaterials and tissues is vital for their development and functionalization. Herein, we suggest the concept of bioadaptability of biomaterials. This concept describes the three most important aspects that can determine the performance of biomaterials in tissue repair： 1） the adaptability of the micro-environment created by biomaterials to the native microenvironment in situ; 2） the adaptability of the mechanical properties of biomaterials to the native tissue; 3） the adaptability of the degradation properties of biomaterials to the new tissue formation. The concept of bioadaptability emphasizes both the material＇s characteristics and biological aspects within a certain micro-environment and molecular mechanism. It may provide new inspiration to uncover the interaction mechanism of biomaterials and tissues, to foster the new ideas of functionalization of biomaterials and to investigate the fundamental issues during the tissue repair process by biomaterials. Furthermore, designing biomaterials with such bioadaptability would open a new door for repairing and regenerating organs or tissues. In this review, we summarized the works in recent years on the bioadaptability of biomaterials for tissue repair applications.
基金supported by the National Natural Science Foundation of China(Nos.51931001 and U22A20121)the Fund for International Cooperation and Exchange between NSFC(China)and CNR(Italy)(NSFC–CNR No.52011530392)the Fund for International Cooperation and Exchange between NSFC(China)and RFBR(Russia)(NSFC-RFBR No.52111530042).
文摘The implants made of metallic biomaterials help healing the bone fracture but also affect the bone repair process.As proposed in Matter 4(2021)2548–2650 by Wang et al.,a precisely adaptable biomaterial ought to recapitulate the targeted tissue with spatiotemporal precision and hierarchical accuracy,ranging from atoms and molecules(genes,proteins,etc.)to cells(including organelles)and to tissues and organs.In comparison to traditional bio-inert metallic bone implants such as Co-based alloys and Ti alloys,biodegradable metal(Mg and Zn alloys)bone implants had been developed and might arise many unexpected variables in the bone repair,due to their bioactive nature.In this paper,the bone repair without and with the presence of metallic implants is compared.Thereafter,the perspectives concerning the interactions between the bone tissues and biodegradable metal implants are put forward,and how to better mimic in vivo biodegradation by in vitro experiments is proposed for further research and development of biodegradable metals.
文摘A variety of techniques have been used for treating avascular necrosis of the femoral head(ANFH),but have frequently failed.In this study,we proposed aβ-TCP system for the treatment of ANFH by boosting revascularization and bone regeneration.The angio-conductive properties and concurrent osteogenesis of the highly interconnected porousβ-TCP scaffold were revealed and quantified through an in vivo model that simulated the ischemic environment of ANFH.Mechanical test and finite element analysis showed that the mechanical loss caused by tissue necrosis and surgery was immediately partially compensated after implantation,and the strength of the operated femoral head was adaptively increased and eventually returned to normal bone,along with continuous material degradation and bone regeneration.For translational application,we further conducted a multi-center open-label clinical trial to assess the efficacy of theβ-TCP system in treating ANFH.Two hundred fourteen patients with 246 hips were enrolled for evaluation,and 82.1%of the operated hips survived at a 42.79-month median follow-up.The imaging results,hip function,and pain scores were dramatically improved compared to preoperative levels.ARCO stage II disease outperformed stage III in terms of clinical effectiveness.Thus,bio-adaptive reconstruction using theβ-TCP system is a promising hip-preserving strategy for the treatment of ANFH.
基金supported by the National Natural Science Foundation of China(Nos.51271117 and 81371935)the Biomedical Program of Science and Technology Innovation Project supported by Shanghai(Nos.14441901800 and 14441901802)
文摘Magnesium （Mg） has been widely accepted as osteoconductive biomaterial, but osseointegration of Mg device at different implantation sites is still unclear. In the present study, high-purity magnesium （HP Mg） pins were implanted into femoral shaft and condyle of New Zealand rabbits concurrently. 2, 8, 12 and 16 weeks after surgery, rabbit femurs were harvested for micro-computed tomography （micro-CT） scanning and subsequent histological examinations. HP Mg pins were retrieved for scanning electron microscope and energy dispersive spectrum （SEM/EDS） analyses. HP Mg pins at both implantation sites performed stable corrosion with mineral deposition and bone incorporation on surface. However, difference in distribution of contact osteogenesis centers and biological properties of peri-implant bone tissues was detected between femoral shaft and femoral condyle. In femoral condyle, contact osteogenesis centers originated from both periosteum and cancellous bones and the whole HP Mg pin was encapsuled in trabecular bone at 16 weeks. Meanwhile, bone volume to total bone volume （BV/TV） and bone mineral density （BMD） of peri-implant bone tissues were above those of normal bone tissues. In femoral shaft, contact osteogenesis centers were only from periosteum and direct bone contact was confined in cortical bone, while BV/TV and BMD kept lower than normal. Furthermore, new formation of peri-implant bone tissues was more active in femoral condyle than in femoral shaft at 16 weeks. Therefore, although HP Mg performed good biocompatibility and corrosion behavior in vivo, its bioadaption of osseointegration at different implantations sites should be taken into consideration. Bone metaphysic was suitable for Mg devices where peri-implant bone tissues regenerated rapidly and the biological properties were close to normal bone tissues.
基金supported by the National Basic Research Program of China (No. 2012CB619101)
文摘In this work, porous Ti6Al4V alloys with 30%-70% porosity for biomedical applications were fabricated by diffusion bonding of alloy meshes. Pore structure was characterized by Micro-CT and SEM. Compressive behavior in the out-of-plane direction and biocompatibility with cortical bone were studied. The results reveal that the fabricated porous Ti6Al4V alloys possess anisotropic structure with square pores in the in-plane direction and elongated pores in the out-of-plane direction. The average pore size of porous Ti6Al4V alloys with 30%-70% porosity is in the range of 240-360 Bin. By tailoring diffusion bonding temperature, aspect ratio of alloy meshes and porosity, porous Ti6Al4V alloys with different compressive properties can be obtained, for instance, Young＇s modulus and yield stress in the ranges of 4-40 GPa and 70-500 MPa, respectively. Yield stress of porous Ti6Al4V alloys fabricated by diffusion bonding is close to that of alloys fabricated by rapid prototyping, hut higher than that of fabricated by powder sintering and space-holder method. Diffusion bonding temperature has some effects on the yield stress of porous Ti6Al4V alloys, but has a minor effect on the Young＇s modulus. The relationship between compressive properties and relative density conforms well to the Gibson-Ashby model. The Young＇s modulus is linear with the aspect ratio, while the yield stress is linear with the square of aspect ratio of alloy meshes. Porous Ti6Al4V alloys with 60%-70% porosity have potential for cortical bone implant applications.
文摘Tissue repair is always a complex process and artificial biomaterials have never been perfect. For example, the mismatch of mechanical property between biomaterials and the host can result in stress shielding; the asynchronous biodegradation rate of biomaterials and tissue regeneration may extend the repair time.
基金supported by the National Basic Research Program of China(973 Program,No.2012CB619105)the China Postdoctoral Science Foundation(Nos.2013M531876 and 2014T70826)+4 种基金the National Natural Science Foundation of China(Nos.31430030,81272041,81071512 and 31170902)the Natural Science Foundation of Guangdong Province(Nos.2014A030310466 and 2013B060300007)the Foundation of Shenzhen Committee for Science and Technology Innovation(Nos.CXZZ20130516103023168 and 2015-336,2013-950)the Jiangxi Province Science and Technology Support Plan Project(No.2010BSA14800)the Guangdong Provincial Key Laboratory of Orthopaedics and Tranmstology
文摘Biomaterials are increasingly being evolved to actively adapt to the desired microenvironments so as to introduce tissue integration, reconstruct stability, promote regeneration, and avoid immune rejection. The complexity of its mechanisms poses great challenge to current biomimetic synthetic materials. Although still at initial stage, harnessing cells, tissues, or even entire body to synthesize bioadaptive materials is introducing a promising future.
