Nanomaterials for Medical Implants
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where the metal coating is held outside the cup. On the other hand, modular cups
are usually made up of two cups, a liner, and a shell. The liner is designed inside
with a locking mechanism, while the shell is made up of metal with a porous coating
outside. Also, a fixation is achieved for bone growth over the porous coating. Further,
the screws are used for the lag of the shell to the bone for providing more fixation.
Hence, Cp-Ti and its alloys can be used for hard tissue replacements, artificial bones,
and hip joints.
2.4 Cardiovascular Implants
Cardiovascular implants are stents that are mostly used for the treatment of cardiovascular diseases for most of the frequent cases. Stents used for cardiovascular applications consist of several metallic materials like stainless steel, Ti, Co-Cr, Au alloys, etc.
for the permanent implants and Mg-Zn alloys are widely used as degradable implants.
It has recently received considerable attention on shape memory alloy (NITINOL and
Co-Cr alloys) as intravascular devices mainly used for stents and occlusion coils. Ti
alloys possess a strong, inert, non-magnetic nature, which has got the main advantage
for cardiovascular applications. A powerful diagnostic tool like MRI (magnetic resonance imaging) has produced a few artifacts was not sufficient due to radio-opaque
in finer structures. The materials used for both the blood-contacting surface and the
mechanical pump components are the artificial heart and cardiovascular circulatory
assist devices. Generally, the metallic stents are coated with drug-loaded polymers
as a local drug reservoir to fabricate the drug-eluting stents (DES). The usage of
DES reduces the rate of in-stent restenosis by introducing local anti-inflammatory
and anti-proliferative therapeutics [31–37].
A versatile top-down approach develops biodegradable fibrous nanoplatforms as
a coating formation through DES through electrospinning deposition method, which
is very cost-effective. As a biodegradable material, it has been proven that polylactic
acid (PLA) is a good potential stent material for the systems with drug loading.
To combat this DES late thrombosis, a mechanism was suggested for this polymer
coating, which can act as a storage release after the implantation with inflammation by
a controlled manner are well associated with DES [38, 39]. Due to its anti-thrombotic
effect, the pharmaceutical agent, like dipyridamole (DPM) is frequently used along
with the combination of salicylic acid repeatedly for the patients who are in the
dangerous condition (secondary stroke). It can be seen that the results of DPM exhibit
the formation of a thrombus and platelet segregation in humans. The major role of
DPM is the resultant inhibition along with vascular cells of equilibrative nucleotide
transporters, which uptake the extracellular adenosine into platelets. Therefore, it can
inhibit the proliferation of vascular cells with smooth muscle cells from preventing
the restenosis of vascular grafts. It activates the surface of the cell with the adenosine receptors, which will increase the intracellular concentration (cyclic adenosine
monophosphate) with anti-inflammatory properties [40]. Electrospinning deposition
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where the metal coating is held outside the cup. On the other hand, modular cups
are usually made up of two cups, a liner, and a shell. The liner is designed inside
with a locking mechanism, while the shell is made up of metal with a porous coating
outside. Also, a fixation is achieved for bone growth over the porous coating. Further,
the screws are used for the lag of the shell to the bone for providing more fixation.
Hence, Cp-Ti and its alloys can be used for hard tissue replacements, artificial bones,
and hip joints.
2.4 Cardiovascular Implants
Cardiovascular implants are stents that are mostly used for the treatment of cardiovascular diseases for most of the frequent cases. Stents used for cardiovascular applications consist of several metallic materials like stainless steel, Ti, Co-Cr, Au alloys, etc.
for the permanent implants and Mg-Zn alloys are widely used as degradable implants.
It has recently received considerable attention on shape memory alloy (NITINOL and
Co-Cr alloys) as intravascular devices mainly used for stents and occlusion coils. Ti
alloys possess a strong, inert, non-magnetic nature, which has got the main advantage
for cardiovascular applications. A powerful diagnostic tool like MRI (magnetic resonance imaging) has produced a few artifacts was not sufficient due to radio-opaque
in finer structures. The materials used for both the blood-contacting surface and the
mechanical pump components are the artificial heart and cardiovascular circulatory
assist devices. Generally, the metallic stents are coated with drug-loaded polymers
as a local drug reservoir to fabricate the drug-eluting stents (DES). The usage of
DES reduces the rate of in-stent restenosis by introducing local anti-inflammatory
and anti-proliferative therapeutics [31–37].
A versatile top-down approach develops biodegradable fibrous nanoplatforms as
a coating formation through DES through electrospinning deposition method, which
is very cost-effective. As a biodegradable material, it has been proven that polylactic
acid (PLA) is a good potential stent material for the systems with drug loading.
To combat this DES late thrombosis, a mechanism was suggested for this polymer
coating, which can act as a storage release after the implantation with inflammation by
a controlled manner are well associated with DES [38, 39]. Due to its anti-thrombotic
effect, the pharmaceutical agent, like dipyridamole (DPM) is frequently used along
with the combination of salicylic acid repeatedly for the patients who are in the
dangerous condition (secondary stroke). It can be seen that the results of DPM exhibit
the formation of a thrombus and platelet segregation in humans. The major role of
DPM is the resultant inhibition along with vascular cells of equilibrative nucleotide
transporters, which uptake the extracellular adenosine into platelets. Therefore, it can
inhibit the proliferation of vascular cells with smooth muscle cells from preventing
the restenosis of vascular grafts. It activates the surface of the cell with the adenosine receptors, which will increase the intracellular concentration (cyclic adenosine
monophosphate) with anti-inflammatory properties [40]. Electrospinning deposition