Nanomaterials for Medical Implants
305
defects with a huge number of dislocations occur during this process. Furthermore,
the collision of balls will cause the fracture and continuous cold welding of the
particles in the atomic scale range. The increase of milling time further leads to the
increase of the elementary components area’s particle size, which will decrease the
length from the micrometer to the sub-micrometer scale. The alloying process mainly
involves repeated continuous fracturing, welding of powder particles rewelding with
a high energy ball mill under or/not by the protective atmosphere. Process controlling agents like toluene, stearic acid, and methanol, etc. are usually employed for
excessive cold welding and rewelding during the milling process. This process is
widely used to control and achieve from alloy powders to nanocrystalline for various
materials with a wide range. [14, 15].
2 Various Applications of Nanostructured Biomedical
Implant Devices
2.1 Dental Implants /Prosthodontics
Dental implants are widely used to provide support as dental prostheses, crowns,
bridges, or dentures with a supported implant and an anchorage in orthodontic
tooth movement. These dental implants are frequently used as single implants in
any situation for the replacement of a missing tooth and all cases, including total
and partial edentulism. Metallic implants, in particular, Ti alloys, are used widely
in dental implants as they have higher mechanical strength and chemical stabilities.
However, bone-bonding abilities, antibacterial activity, and cell adhesion performances on polished Ti implants during service still lack. Acceleration of possible
ways is the osseointegration, i.e., the direct bone bonding of living tissues with
the surgical implants is to fabricate the surface with micro-nano surface roughness
called micro/nanotextured surfaces. The nano surfaces fabricated on the implant
could enlarge the contact area on the implant with living cells, thus enhancing the
osseointegration. Interestingly, the nano surface with enhanced wettability further
enhances the bone mineralization and osteoblast differentiation. Several surface
coating methodologies are reported to modify the metallic surfaces with micro/nano
morphologies, accelerating the osseointegration. Electrochemical oxidation is the
most commonly used technique which is widely applied for Ti alloys to fabricate the
nano surface with pores and tubes with different morphological features with varying
chemical composition. The MAO (micro-arc oxidation) process is used to fabricate
the nanoscale porous structure (F10–300 nm) and micro-sized slots (3–7 µm) with
nano-sized pores (F10–300 nm) with duty cycles and durations of 9%–2 min and
11%–13 min, respectively in 0.1 mol/l Li 2 B 4 O 7 [16].
The coatings are composed of rutile and anatase phases; further, the increase of
coating duration increased the rutile phase due to the higher voltage and the reaction
temperature. Further, the static CA (contact angle) value of the 13 min coated alloy
305
defects with a huge number of dislocations occur during this process. Furthermore,
the collision of balls will cause the fracture and continuous cold welding of the
particles in the atomic scale range. The increase of milling time further leads to the
increase of the elementary components area’s particle size, which will decrease the
length from the micrometer to the sub-micrometer scale. The alloying process mainly
involves repeated continuous fracturing, welding of powder particles rewelding with
a high energy ball mill under or/not by the protective atmosphere. Process controlling agents like toluene, stearic acid, and methanol, etc. are usually employed for
excessive cold welding and rewelding during the milling process. This process is
widely used to control and achieve from alloy powders to nanocrystalline for various
materials with a wide range. [14, 15].
2 Various Applications of Nanostructured Biomedical
Implant Devices
2.1 Dental Implants /Prosthodontics
Dental implants are widely used to provide support as dental prostheses, crowns,
bridges, or dentures with a supported implant and an anchorage in orthodontic
tooth movement. These dental implants are frequently used as single implants in
any situation for the replacement of a missing tooth and all cases, including total
and partial edentulism. Metallic implants, in particular, Ti alloys, are used widely
in dental implants as they have higher mechanical strength and chemical stabilities.
However, bone-bonding abilities, antibacterial activity, and cell adhesion performances on polished Ti implants during service still lack. Acceleration of possible
ways is the osseointegration, i.e., the direct bone bonding of living tissues with
the surgical implants is to fabricate the surface with micro-nano surface roughness
called micro/nanotextured surfaces. The nano surfaces fabricated on the implant
could enlarge the contact area on the implant with living cells, thus enhancing the
osseointegration. Interestingly, the nano surface with enhanced wettability further
enhances the bone mineralization and osteoblast differentiation. Several surface
coating methodologies are reported to modify the metallic surfaces with micro/nano
morphologies, accelerating the osseointegration. Electrochemical oxidation is the
most commonly used technique which is widely applied for Ti alloys to fabricate the
nano surface with pores and tubes with different morphological features with varying
chemical composition. The MAO (micro-arc oxidation) process is used to fabricate
the nanoscale porous structure (F10–300 nm) and micro-sized slots (3–7 µm) with
nano-sized pores (F10–300 nm) with duty cycles and durations of 9%–2 min and
11%–13 min, respectively in 0.1 mol/l Li 2 B 4 O 7 [16].
The coatings are composed of rutile and anatase phases; further, the increase of
coating duration increased the rutile phase due to the higher voltage and the reaction
temperature. Further, the static CA (contact angle) value of the 13 min coated alloy