A review on biomedical and dental applications of cerium oxide nanoparticles ― Unearthing the potential of this rare earth metal

Nanotechnology deals with particles ranging from 1 to 100 nm in size called as nanoparticles. These nano particles exhibit unique properties which find an application in many industries and medical fields. A growing body of evidence points out the newer developing technologies adopted in the field of medicine in terms of target therapies, imaging systems, drug deliveries, etc. is through the incorporation of nanoparticles. Cerium oxide nanoparticles have gained attention in the last decade due to exceptional properties such as redox activity, biofilm inhibition, antibacterial activity, anti-inflammatory activity, etc. The method of synthesis of cerium oxide nanoparticles plays a pivotal role in its application. It exhibits redox properties and catalytic activity and thus has found its use in biomedical applications. Nanoparticles are incorporated into dental materials such as restorative cements/sealants, adhesives, and denture systems to improve their properties. Among the various metal oxide nanoparticles, cerium oxide nanoparticles (CeO2NPs) are known to exhibit lower toxicity to mammalian cells and possess unique antibacterial mechanism. In addition, they exhibit potent properties such as antitumor, anti-inflammatory, antibacterial activities, and functions as an immunosensor. CeO2NPs have excellent scavenging properties for reactive oxygen species, which is why they are being considered for therapeutic purposes. In this review, various methods of synthesis of CeO2NPs are discussed. Several factors that determine the particle size and morphology of these materials are important for biomedical and dental applications. Emphasis is given to preparation methods and variables such as calcination temperature, which have a profound effect on particle size and morphology. This article also presents various applications of CeO2NPs in the biomedical and dental fields.