Laser Induced Micro/Nano …
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development is found to improve the alloy properties, however, the tolerance limits
of each element need to be considered to avoid the adverse effects.
Therefore, surface treatments are adopted to satisfy the requirement of various
implant materials. Among them applying the surface coatings to fabricate
micro/nanostructures on various implant materials to enhance the surface properties
are commonly studied. Several inorganic/organic coatings are developed to simultaneously enhance the degradation properties and biocompatibility of implant materials. Despite their interesting properties, the surface coatings have certain limitations
such as adhesion to the substrate, therefore appropriate coating conditions are essential to achieve good quality coatings on implant materials. The surface nature of the
implant materials also plays a key role in determining the cell attachment behavior
and hence it is important to control the surface textures to enhance the cell attachment
and proliferation. Human mesenchymal stem cells (hMSCs) adhesion and differentiation were significantly varied with micro/nano topographies produced on Ti alloy
using femtosecond laser [4]. Micro and nano grid topographies were beneficial for
the cell colonization by anchoring the cells and cell locomotion, respectively, and
cell adhesion was promoted by the superimposed micro/nano grids. Furthermore,
the bio-mineralization process also varies based on the surface nature of the material. Hence, surface modification is essential to alter the surface properties of the
biomaterials in various applications.
Several surface modification treatments such as physicochemical, mechanical
treatments, biomimetic process, vacuum processes, and high energy processes are
widely used to fabricate the surface properties of biomaterials. Each of these methods
has its advantages as well as disadvantages. Surface modification using lasers is given
importance in recent research owing to its high precision process and controlled
surface morphologies. Also, laser processing is a non-contact process, has high
repeatability, pollution-free, and produces a small heat-affected zone on the processed
materials, thus controlling the material properties. Several studies carried out on laser
processed hierarchical surface patterned Ti-based alloys indicated that the bonding
ability of the bone was better on the textured surfaces compared to polished and other
processed surfaces. Furthermore, the osteogenesis increased on the textured surfaces
and inhibit the adipogenesis of mesenchymal stem cells (MSCs). The surface coatings followed by laser processing also significantly altered the osseointegration of
the implant materials. Anti-bacterial properties of surgical metallic materials are
one of the important factors, and the usage of ultra-fast laser treatment produces
biomimetic textures with different wettability properties. The surface wettability
and size/nature (hydrophilic/hydrophobic) of bacteria alter the bacterial attachment,
and their colonization, thus surface can be designed accordingly. The picosecond
and femtosecond lasers are widely used to fabricate the nanoscale structures with
micro/nanoscale periodicity and nano ripples. Laser texturing is a precise technique,
which can also control the parameters such as, pulse energy, scan speed, spacing,
and the number of passes to fabricate the structures with sizes similar and larger
than the bacterial cell sizes, which could alter the wettability and following bacterial
adhesion properties [5]. Metal nanoparticles are widely used for localized surface
plasmon resonance (LSPR) sensing and the particles enhance the signal intensities of
441
development is found to improve the alloy properties, however, the tolerance limits
of each element need to be considered to avoid the adverse effects.
Therefore, surface treatments are adopted to satisfy the requirement of various
implant materials. Among them applying the surface coatings to fabricate
micro/nanostructures on various implant materials to enhance the surface properties
are commonly studied. Several inorganic/organic coatings are developed to simultaneously enhance the degradation properties and biocompatibility of implant materials. Despite their interesting properties, the surface coatings have certain limitations
such as adhesion to the substrate, therefore appropriate coating conditions are essential to achieve good quality coatings on implant materials. The surface nature of the
implant materials also plays a key role in determining the cell attachment behavior
and hence it is important to control the surface textures to enhance the cell attachment
and proliferation. Human mesenchymal stem cells (hMSCs) adhesion and differentiation were significantly varied with micro/nano topographies produced on Ti alloy
using femtosecond laser [4]. Micro and nano grid topographies were beneficial for
the cell colonization by anchoring the cells and cell locomotion, respectively, and
cell adhesion was promoted by the superimposed micro/nano grids. Furthermore,
the bio-mineralization process also varies based on the surface nature of the material. Hence, surface modification is essential to alter the surface properties of the
biomaterials in various applications.
Several surface modification treatments such as physicochemical, mechanical
treatments, biomimetic process, vacuum processes, and high energy processes are
widely used to fabricate the surface properties of biomaterials. Each of these methods
has its advantages as well as disadvantages. Surface modification using lasers is given
importance in recent research owing to its high precision process and controlled
surface morphologies. Also, laser processing is a non-contact process, has high
repeatability, pollution-free, and produces a small heat-affected zone on the processed
materials, thus controlling the material properties. Several studies carried out on laser
processed hierarchical surface patterned Ti-based alloys indicated that the bonding
ability of the bone was better on the textured surfaces compared to polished and other
processed surfaces. Furthermore, the osteogenesis increased on the textured surfaces
and inhibit the adipogenesis of mesenchymal stem cells (MSCs). The surface coatings followed by laser processing also significantly altered the osseointegration of
the implant materials. Anti-bacterial properties of surgical metallic materials are
one of the important factors, and the usage of ultra-fast laser treatment produces
biomimetic textures with different wettability properties. The surface wettability
and size/nature (hydrophilic/hydrophobic) of bacteria alter the bacterial attachment,
and their colonization, thus surface can be designed accordingly. The picosecond
and femtosecond lasers are widely used to fabricate the nanoscale structures with
micro/nanoscale periodicity and nano ripples. Laser texturing is a precise technique,
which can also control the parameters such as, pulse energy, scan speed, spacing,
and the number of passes to fabricate the structures with sizes similar and larger
than the bacterial cell sizes, which could alter the wettability and following bacterial
adhesion properties [5]. Metal nanoparticles are widely used for localized surface
plasmon resonance (LSPR) sensing and the particles enhance the signal intensities of