Titanium and titanium alloys are widely used in biomedical devices and components, especially as hard tissue replacements as well as in cardiac and cardiovascular applications, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, titanium and its alloys cannot meet all of the clinical requirements. Therefore, in order to improve the biological, chemical, and mechanical properties, surface modification is often performed. This article reviews the various surface modification technologies pertaining to titanium and titanium alloys including mechanical treatment, thermal spraying, sol–gel, chemical and electrochemical treatment, and ion implantation from the perspective of biomedical engineering. Recent work has shown that the wear resistance, corrosion resistance, and biological properties of titanium and titanium alloys can be improved selectively using the appropriate surface treatment techniques while the desirable bulk attributes of the materials are retained. The proper surface treatment expands the use of titanium and titanium alloys in the biomedical fields. Some of the recent applications are also discussed in this paper.

/pdf/surface-modification-of-titanium-titanium-alloys-and-related-176rvxu9wp.pdf

Surface modification of titanium, titanium alloys, and related materials for biomedical applications

Lanthanide-based luminescent hybrid materials.

The antibacterial action of silver is utilized in numerous consumer products and medical devices. Metallic silver, silver salts, and also silver nanoparticles are used for this purpose. The state of research on the effect of silver on bacteria, cells, and higher organisms is summarized. It can be concluded that the therapeutic window for silver is narrower than often assumed. However, the risks for humans and the environment are probably limited.

Silver as Antibacterial Agent: Ion, Nanoparticle, and Metal

https://pure.hw.ac.uk/ws/files/10766137/Melchels2010_Biomaterials_31_24_6121.pdf

A review on stereolithography and its applications in biomedical engineering

In the laser treatment of a workpiece (9), e.g. for surface hardening, melting, alloying, cladding, welding or cutting, the adverse effect of reflectivity of the surface, when a pure, monochromatic laser (6) is used, is remedied by the simultaneous application of a relatively shorter wavelength beam (1). The two beams (1)(5) may be combined by a beam coupler (4) or may reach the workpiece (9) by separate optical paths (not shown). The shorter wavelength beam (1) improves the coupling efficiency of the higher- powered laser beam (5).

Laser Material Processing

Preparation and characterisation of titania/hydroxyapatite composite coatings obtained by sol-gel process.

Synthesis and characteristics of fly ash and bottom ash based geopolymers–A comparative study

Highly loaded hydroxyapatite microsphere/ PLA porous scaffolds obtained by fused deposition modelling

Bacterial cellulose (BC) functionalized with silver nanoparticles (AgNPs) is evaluated as an antimicrobial membrane for wound-healing treatment. A facile green synthesis of silver nanoparticles inside the porous three-dimensional weblike BC network has been obtained by UV light irradiation. AgNPs were photochemically deposited onto the BC gel network as well as they were chemically bonded to the cellulose fiber surfaces. AgNPs with a narrow size distribution along with some aggregates in the BC network were evidenced from the morphological analyses. A highly crystalline nature of the BC membranes was observed in X-ray diffraction measurements, and the presence of metallic silver confirmed the photochemical reduction of Ag+ → Ag0 in Ag/BC composites. Antibacterial activity of the hybrid composites, such as pellicles, performed against the Gram-negative bacteria (Escherichia coli) by disk diffusion and growth dynamics methods showed high bacteria-killing performance. No significant amount of silver release ...

Silver-Functionalized Bacterial Cellulose as Antibacterial Membrane for Wound-Healing Applications.

Silver nanocrystal doped silica films were prepared by the sol-gel process. The sol was prepared from 1:0.12:12:0.2:6:7 molar ratios of Si(OC2H5)4:AgNO3:H2O:HNO3:C3nH7OH:C4iH9OH. The glassy, highly transparent film with high dopant concentration (silver/silicon atomic ratio = 0.12) was successfully prepared by the dip-coating method. After drying in air at 60°C for 30 min, samples were heat-treated, in air, at 300, 350, 400, 450, 500 and 550°C using 30–100 min soaking periods for each step in a cumulative heating procedure. Measurements on the films were made by ultraviolet-visible and infrared spectroscopy, X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry and transmission electron microscopy. Mechanisms of silver colloid formation in the densified silica matrix with respect to the thermal treatment are discussed. To understand the formation of silver nanocrystals from the silver silicate network, the corresponding doped bulk gel samples were analyzed by X-ray diffraction and differential scanning calorimetry.

Antonio Licciulli

Papers

Preparation and characterisation of titania/hydroxyapatite composite coatings obtained by sol-gel process.

Synthesis and characteristics of fly ash and bottom ash based geopolymers–A comparative study

Highly loaded hydroxyapatite microsphere/ PLA porous scaffolds obtained by fused deposition modelling

Silver-Functionalized Bacterial Cellulose as Antibacterial Membrane for Wound-Healing Applications.

Silver nanocrystals in silica by sol-gel processing