Corrosion Prevention of Biomedical Implants: Surface Coating Techniques Perspective

No doubt, the use of biomedical implants in the world has been of tremendous benefit to humans (animals as well), still gaining much relevance today, and commands greater prospects in the future. Developments in this field have been from the progression of the use of materials like wood, iron and gold as external limb support and indental applications, to more sophisticated materials today like biodegradable metal alloys, polymers, ceramics and composites materials capable of replacing damaged or worn-out organs (eye, heart, lungs, liver, kidney, etc.), mimicking the bone, or for boosting other physiological features as in cosmetology. Appropriate applications of these implants in the human body still remain a challenge today due to several post-surgical issues like cytotoxicity, thrombogenicity, allergenicity, carcinogenicity and inflammations all of which could be attributed to factors like biocompatibility, osseointegration, mechanical properties and corrosion resistance of these biomedical implants during service. The aspect of implants’ corrosion is of much concern in the biomedical industry of which there have been several methods used to tackle it viz -use of corrosion resistant materials and inhibitors, metal plating, environmental and design considerations and protective coating techniques. This paper reviews five different surface coating techniques for preventing corrosion in biomedical implants, their descriptions and working principles.