Nanomaterials for Medical Implants
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1.3.3 Ion Implantation
The ion implantation process involves the arrangement of atoms that enable injecting
the element to the near-surface region, which results in hydroxyapatite layer formation over the metal surfaces. It has been synthesized by the implantation of calcium
and phosphate ions. This method mainly uses a high energy beam (10 keV) ions over
the metal surface, which falls over the vacuum chamber. The incident ions come
to rest due to their energy loss in the near-surface region because of the collision
between substrate and incident ions [6–11]. The major advantages of this method
are as follows:
a. High purity layers with ultra-clean process
b. Easy control and determination with concentration and depth of impurities
c. Excellent adhesion of the coating to an implanted surface
d. Effect free properties (bulk) of the substrate because of its low substrate level
e. Easily controllable and reproducible
Chemical methods are used to modify the surface of implant material in the
nanoscale range. Anodic oxidation, combined anodization with chemical etching,
etching, acid treatment, alkali treatment, hydrogen peroxide treatment, nanoparticle
deposition methods (sol-gel process), chemical deposition, combined chemical vapor
deposition are the common chemical methods widely used to fabricate the micro/nano
surfaces [6].
1.3.4 Anodic Oxidation
The anodic oxidation process is generally carried out on smooth Ti or Mg implant
surfaces to fabricate nanotubular structures (< 100 nm in diameter). Physicochemical
surface properties, spacing, and diameter of nanotubes can be controlled with varying
current density, voltage, electrolyte composition, and temperature. The anodization
process leads to the formation of nanostructures with a pillar form of large nanotube
arrays of tunable size with 10 µm on multi-walled nanotubes, nano HAp coatings
(15–25 nm) are deposited on Ti or Mg surfaces to improve bioactivity, which is
essential for implant materials [6].
1.3.5 Combined Anodization with Chemical Etching
This method is a combination of both anodization and chemical etching combined to
form the reaction with metal or polymers. Anodized nanotubular Ti or Mg surfaces
are coated by treating with sodium hydroxide (NaOH) with nanoporous poly (lacticco-glycolic acid) to stimulate cell activity. However, it can be seen that there is no
301
1.3.3 Ion Implantation
The ion implantation process involves the arrangement of atoms that enable injecting
the element to the near-surface region, which results in hydroxyapatite layer formation over the metal surfaces. It has been synthesized by the implantation of calcium
and phosphate ions. This method mainly uses a high energy beam (10 keV) ions over
the metal surface, which falls over the vacuum chamber. The incident ions come
to rest due to their energy loss in the near-surface region because of the collision
between substrate and incident ions [6–11]. The major advantages of this method
are as follows:
a. High purity layers with ultra-clean process
b. Easy control and determination with concentration and depth of impurities
c. Excellent adhesion of the coating to an implanted surface
d. Effect free properties (bulk) of the substrate because of its low substrate level
e. Easily controllable and reproducible
Chemical methods are used to modify the surface of implant material in the
nanoscale range. Anodic oxidation, combined anodization with chemical etching,
etching, acid treatment, alkali treatment, hydrogen peroxide treatment, nanoparticle
deposition methods (sol-gel process), chemical deposition, combined chemical vapor
deposition are the common chemical methods widely used to fabricate the micro/nano
surfaces [6].
1.3.4 Anodic Oxidation
The anodic oxidation process is generally carried out on smooth Ti or Mg implant
surfaces to fabricate nanotubular structures (< 100 nm in diameter). Physicochemical
surface properties, spacing, and diameter of nanotubes can be controlled with varying
current density, voltage, electrolyte composition, and temperature. The anodization
process leads to the formation of nanostructures with a pillar form of large nanotube
arrays of tunable size with 10 µm on multi-walled nanotubes, nano HAp coatings
(15–25 nm) are deposited on Ti or Mg surfaces to improve bioactivity, which is
essential for implant materials [6].
1.3.5 Combined Anodization with Chemical Etching
This method is a combination of both anodization and chemical etching combined to
form the reaction with metal or polymers. Anodized nanotubular Ti or Mg surfaces
are coated by treating with sodium hydroxide (NaOH) with nanoporous poly (lacticco-glycolic acid) to stimulate cell activity. However, it can be seen that there is no