Magnesium has been a focal point of significant exploration in the biomedical engineering domain for many years due to its exceptional attributes, encompassing impressive specific strength, low density, excellent damping abilities, biodegradability, and the sought-after quality of biocompatibility. The primary drawback associated with magnesium-based implants is their susceptibility to corrosion and wear in physiological environments, which represents a significant limitation. Research findings have established that plasma electrolytic oxidation (PEO) induces substantial modifications in the surface characteristics and corrosion behavior of magnesium and its alloy counterparts. By subjecting the surface to high voltages, a porous ceramic coating is formed, resulting in not only altered surface properties and corrosion resistance, but also enhanced wear resistance. However, a drawback of the PEO process is that excessive pore formation and porosity within the shell could potentially undermine the coating’s corrosion and wear resistances. Altering the electrolyte conditions by introducing micro- and nano-particles can serve as a valuable approach to decrease coating porosity and enhance their ultimate characteristics. This paper evaluates the particle adhesion, composition, corrosion, and wear performances of particle-incorporated coatings applied to magnesium alloys through the PEO method.

Over the past decade, metallic drug-eluting implants have gained significance in orthopedic and dental applications for controlled drug release, specifically for preventing infection associated with implants. Recent studies showed that metallic implants loaded with drugs were substituted for conventional bare metal implants to achieve sustained and controlled drug release, resulting in a desired local therapeutic concentration. A number of secondary features can be provided by the incorporated active molecules, including the promotion of osteoconduction and angiogenesis, the inhibition of bacterial invasion, and the modulation of host body reaction. This paper reviews recent trends in the development of the metallic drug-eluting implants with various drug delivery systems in the past three years. There are various types of drug-eluting implants that have been developed to meet this purpose, depending on the drug or agents that have been loaded on them. These include anti-inflammatory drugs, antibiotics agents, growth factors, and anti-resorptive drugs.

Titanium (Ti) and its alloys are widely used as dental implant materials because of their high mechanical properties, biocompatibility, and corrosion resistance. This research was undertaken to study the effect of polymethyl-methacrylate (PMMA) sealing layer on the corrosion performance of plasma electrolytic oxidation (PEO)-coated titanium-based dental implants in pure saliva and fluoride-containing saliva solutions. The phase structure, chemical composition, and microstructure of coatings were investigated via x-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy, respectively. The corrosion behavior of the samples was evaluated by open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy tests. The deposition of the PMMA layer on the PEO-coated Ti dental implants was found to effectively seal the micropores and microcracks of the TiO₂ coatings and block corrosive ions’ penetration routes through the coating. Thereby, the results indicated that better corrosion performance was observed when the PMMA layer is applied on PEO-coated Ti dental implants than on the simple PEO coatings.

The failure of a titanium implant is often attributed to inflammatory reactions following implantation. This study focuses on the synthesis of a polyethylene glycol (PEG) layer on porous titanium dioxide (TiO₂) coatings using plasma electrolytic oxidation (PEO). This PEG layer serves as a foundation for a drug-eluting platform designed to respond to pH stimuli during inflammation. Betamethasone (BET), a widely used anti-inflammatory drug, was loaded onto the pH-responsive functional PEG layers. The application of the PEG-BET layer onto TiO₂ coatings through the vacuum dip coating method resulted in a pH-sensitive sustained release of BET over a 30-day period. Notably, the release rates were 81% at pH 5.0 and 55% at pH 7.2. Electrochemical corrosion tests conducted in both normal and acidic inflammatory solutions demonstrated that duplex composite coatings offer superior protection compared to simple oxide coatings. In a pH 5.0 solution, corrosion current density measurements revealed values of 1.75 μA cm⁻² (PEO/PEG-BET), 8.87 μA cm⁻² (PEO), and 49.17 μA cm⁻² (bare titanium). These results highlight the effectiveness of the PEO/PEG-BET layer in sealing pores within PEO coatings, subsequently reducing the infiltration of corrosive ions in inflammatory environments.

Metallic biomedical implants are made from materials such as stainless steel, titanium, magnesium, and cobalt-based alloys. As a degradable biometal, magnesium (Mg) and its alloys are becoming more popular for applications in bone tissue engineering. Mg-based alloys have been found to be biocompatible, bioabsorbable, and bioactive, allowing them to be used as orthopedic implants with a low Young’s modulus. Computer-aided design can be used to design scaffolds with intricate porous structures based on patient-specific anatomical data. These models can be materialized rapidly and with reasonably acceptable dimensional accuracy by additive manufacturing (AM) techniques. It is known that lasers are the most widely investigated energy source for AM’ed Mg, as they offer some distinct advantages over other forms of energy. Recent studies have focused on developing biodegradable Mg scaffolds by using laser-based AM techniques. In this paper, we aim to review the recent progress of laser-based AM for Mg alloys and survey challenges in the research and future development of AM’ed Mg scaffolds for clinical applications.