Introduction Osteoarthritis （OA） is a degenerative joint disease, characterized by cartilage loss and changes in bone at the interface of a joint resulting in pain, stiffness and reduced mobility. OA is one of the m...Introduction Osteoarthritis （OA） is a degenerative joint disease, characterized by cartilage loss and changes in bone at the interface of a joint resulting in pain, stiffness and reduced mobility. OA is one of the most prevalent chronic conditions as identified in Bone and Joint Decade. According to the World Health Organization, 40% of people over the age of 70 have OA. This joint disease affects around 0.4 billion people with patients in Europe accounting for up to 30%. The figure is set to increase with the ageing problem.展开更多
The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NC...The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NCs)with improved mechanical properties are appealing materials for lightweight structural applications.In contrast to conventional Mg-based composites,the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability.The present article reviews Mg-based metal matrix nanocomposites(MMNCs)with metallic and ceramic additions,fabricated via both solid-based(sintering and powder metallurgy)and liquid-based(disintegrated melt deposition)technologies.It also reviews strengthening models and mechanisms that have been proposed to explain the improved mechanical characteristics of Mg-based alloys and nanocomposites.Further,synergistic strengthening mecha-nisms in Mg matrix nanocomposites and the dominant equations for quantitatively predicting mechanical properties are provided.Furthermore,this study offers an overview of the creep and fatigue behavior of Mg-based alloys and nanocomposites using both traditional(uniaxial)and depth-sensing indentation techniques.The potential applications of magnesium-based alloys and nanocomposites are also surveyed.展开更多
Magnesium(Mg)and its alloys are revolutionizing the field of interventional surgeries in the medical industry.Their high biocompatibility,biodegradability,and a similar elastic modulus to natural bone make porous Mg-b...Magnesium(Mg)and its alloys are revolutionizing the field of interventional surgeries in the medical industry.Their high biocompatibility,biodegradability,and a similar elastic modulus to natural bone make porous Mg-based structures potential candidates for orthopedic implants and tissue engineering scaffolding.However,fabricating and machining porous Mg-based structures is challenging due to their complexity and difficulties in achieving uniform or gradient porosity.This review aims to thoroughly explore various fabrication procedures used to create metallic scaffolds,with a specific focus on those made from Mg-based alloys.Both traditional manufacturing techniques,including the directional solidification of metal-gas eutectic technique,pattern casting,methods using space holders,and modern fabrication methods,which are based on additive manufacturing,are covered in this review article.Furthermore,the paper highlights the most important findings of recent studies on Mg-based scaffolds in terms of their microstructure specifications,mechanical properties,degradation and corrosion behavior,antibacterial activity,and biocompatibility(both in vivo and in vitro).While extensive research has been conducted to optimize manufacturing parameters and qualities of Mg-based scaffolds for use in biomedical applications,specifically for bone tissue engineering applications,further investigation is needed to fabricate these scaffolds with specific properties,such as high resistance to corrosion,good antibacterial properties,osteoconductivity,osteoinductivity,and the ability to elicit a favorable response from osteoblast-like cell lines.The review concludes with recommendations for future research in the field of medical applications.展开更多
Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries ...Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries that were not feasible with traditional manufacturing processes. Researchers can control the structural geometry through a wide range of customisable printing parameters and design choices including material, print path, temperature, and many other process parameters. Currently, the impact of these choices is not fully understood. This review focuses on how the position and orientation of extruded filaments, which sometimes referred to as the print path, lay-down pattern, or simply'scaffold design', affect scaffold properties and biological performance. By analysing trends across multiple studies, new understanding was developed on how filament position affects mechanical properties. Biological performance was also found to be affected by filament position, but a lack of consensus between studies indicates a need for further research and understanding. In most research studies, scaffold design was dictated by capabilities of additive manufacturing software rather than free-form design of structural geometry optimised for biological requirements. There is scope for much greater application of engineering innovation to additive manufacture novel geometries. To achieve this, better understanding of biological requirements is needed to enable the effective specification of ideal scaffold geometries.展开更多
文摘Introduction Osteoarthritis （OA） is a degenerative joint disease, characterized by cartilage loss and changes in bone at the interface of a joint resulting in pain, stiffness and reduced mobility. OA is one of the most prevalent chronic conditions as identified in Bone and Joint Decade. According to the World Health Organization, 40% of people over the age of 70 have OA. This joint disease affects around 0.4 billion people with patients in Europe accounting for up to 30%. The figure is set to increase with the ageing problem.
基金H.R.Bakhsheshi-Rad and S.Sharif would like to acknowledge UTM Research Management for the financial support through the funding(Q.J130000.2409.08G37).
文摘The addition of nanoscale additions to magnesium(Mg)based alloys can boost mechanical characteristics without noticeably decreasing ductility.Since Mg is the lightest structural material,the Mg-based nanocomposites(NCs)with improved mechanical properties are appealing materials for lightweight structural applications.In contrast to conventional Mg-based composites,the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability.The present article reviews Mg-based metal matrix nanocomposites(MMNCs)with metallic and ceramic additions,fabricated via both solid-based(sintering and powder metallurgy)and liquid-based(disintegrated melt deposition)technologies.It also reviews strengthening models and mechanisms that have been proposed to explain the improved mechanical characteristics of Mg-based alloys and nanocomposites.Further,synergistic strengthening mecha-nisms in Mg matrix nanocomposites and the dominant equations for quantitatively predicting mechanical properties are provided.Furthermore,this study offers an overview of the creep and fatigue behavior of Mg-based alloys and nanocomposites using both traditional(uniaxial)and depth-sensing indentation techniques.The potential applications of magnesium-based alloys and nanocomposites are also surveyed.
基金U.S.National Institute of Health-National Heart,Lung,and Blood Institute Grants R56HL163552 and R01HL168696 are acknowledged by J W D for funding work on biodegradable metals.
文摘Magnesium(Mg)and its alloys are revolutionizing the field of interventional surgeries in the medical industry.Their high biocompatibility,biodegradability,and a similar elastic modulus to natural bone make porous Mg-based structures potential candidates for orthopedic implants and tissue engineering scaffolding.However,fabricating and machining porous Mg-based structures is challenging due to their complexity and difficulties in achieving uniform or gradient porosity.This review aims to thoroughly explore various fabrication procedures used to create metallic scaffolds,with a specific focus on those made from Mg-based alloys.Both traditional manufacturing techniques,including the directional solidification of metal-gas eutectic technique,pattern casting,methods using space holders,and modern fabrication methods,which are based on additive manufacturing,are covered in this review article.Furthermore,the paper highlights the most important findings of recent studies on Mg-based scaffolds in terms of their microstructure specifications,mechanical properties,degradation and corrosion behavior,antibacterial activity,and biocompatibility(both in vivo and in vitro).While extensive research has been conducted to optimize manufacturing parameters and qualities of Mg-based scaffolds for use in biomedical applications,specifically for bone tissue engineering applications,further investigation is needed to fabricate these scaffolds with specific properties,such as high resistance to corrosion,good antibacterial properties,osteoconductivity,osteoinductivity,and the ability to elicit a favorable response from osteoblast-like cell lines.The review concludes with recommendations for future research in the field of medical applications.
文摘Material extrusion additive manufacturing has rapidly grown in use for tissue engineering research since its adoption in the year 2000. It has enabled researchers to produce scaffolds with intricate porous geometries that were not feasible with traditional manufacturing processes. Researchers can control the structural geometry through a wide range of customisable printing parameters and design choices including material, print path, temperature, and many other process parameters. Currently, the impact of these choices is not fully understood. This review focuses on how the position and orientation of extruded filaments, which sometimes referred to as the print path, lay-down pattern, or simply'scaffold design', affect scaffold properties and biological performance. By analysing trends across multiple studies, new understanding was developed on how filament position affects mechanical properties. Biological performance was also found to be affected by filament position, but a lack of consensus between studies indicates a need for further research and understanding. In most research studies, scaffold design was dictated by capabilities of additive manufacturing software rather than free-form design of structural geometry optimised for biological requirements. There is scope for much greater application of engineering innovation to additive manufacture novel geometries. To achieve this, better understanding of biological requirements is needed to enable the effective specification of ideal scaffold geometries.
