Magnesium Alloys With Tunable Interfaces as Bone Implant Materials

Abstract

Magnesium (Mg) based biodegradable materials are a new generation orthopedic implant materials that are intended to possess same mechanical properties as that of bone. Mg alloys are considered as promising substitutes to permanent implants due to their biodegradability in the physiological environment. However, rapid corrosion rate is one of the major constraints of using Mg alloys in clinical applications in spite of their excellent biocompatibility. Approaches to overcome the limitations include the selection of adequate alloying elements, proper surface treatment, surface modification with coating to control the degradation rate. This review focuses on current advances on surface engineering of Mg based biomaterials for biomedical applications. The review begins with a description of corrosion mechanism of Mg alloy, the requirement for appropriate surface functionalization/coatings, their structure-property-performance relationship, and suitability for biomedical applications. The control of physico-chemical properties such as wettability, surface morphology, surface chemistry, and surface functional groups of the coating tailored by various approaches forms the pivotal part of the review. Chemical surface treatment offers initial protection from corrosion and inorganic coating like hydroxyapatite (HA) improves the biocompatibility of the substrate. Considering the demand of ideal implant materials, multilayer hybrid coatings on Mg alloy in combination with chemical pretreatment or inorganic HA coating, and protein-based polymer coating could be a promising technique to improve corrosion resistance and promote biocompatibility of Mg-based alloys.

Bioresorbable Magnesium-Based Alloys as Novel Biomaterials in Oral Bone Regeneration: General Review and Clinical Perspectives

“…During the laser peening, expanding plasma induces deep compressive residual stresses which increase fatigue strength and corrosion resistance of the material [138]. Apart from that, other strategies such as surface modification using chemical treatment or coatings by single layer or multilayers have been developed to control the corrosion and degradation while keeping the biocompatibility of Mg [139]. Some Mg alloys were produced by forced molten Mg alloys into a mould cavity under high pressure.…”

A review of additive manufacturing of Mg-based alloys and composite implants

“…The information gathered from the biodegradable bulk material design can help with the primary design of powder composition [89,[110][111][112]. For the enhancement of biocompatibility and mechanical integrity of bulk magnesium alloys during biodegradation, surface biofunctionalization has been carried out [113]. In contrast to other SLM titanium alloys, this alloy is highly biocompatible and has no toxic materials like aluminum or vanadium.…”

Osteoinduction Evaluation of Fluorinated Hydroxyapatite and Tantalum Composite Coatings on Magnesium Alloys

“…Though Mg and its alloys have emerged as a new class of biodegradable metallic materials and can be widely used in orthopedic applications, the lack of biocompatibility and osteoinductive properties limits their widespread application ( Chakraborty Banerjee et al, 2019 ). Therefore, owing to their poor anti-corrosion behavior and the lack of osteogenic properties, the bone and tissue regeneration around Mg alloy implants is observed to be non-optimal ( Lin et al, 2013 ; Yang et al, 2015 ; Liu et al, 2017 ; Rahman et al, 2020 ). In this respect, the surface modification of Mg-based materials plays a pivotal role by improving cellular response without affecting the desirable mechanical properties and enhancing osteogenic properties.…”