Topical anticaries agents are non-invasive methods to control and prevent dental caries. SDF is a fluoride-based agent added to the arsenal of caries prevention tools. It has got a lot of attention since its introduction in the 1970s because of its ability to prevent and arrest caries, as well as its excellent antibacterial and anti-plaque action. SDF reduces acid production by microorganisms, decreases the Streptococcus mutans count, biofilm formation, increases enamel resistance, and promotes dentinal tubule obliteration when applied to the dental surface. SDF also assists in the remineralization of dentin. A biannual application of 38% SDF has been effective at preventing dentin demineralization. This "silver bullet" can be seen as an alternative for caries prevention in special health care needs children which is minimally invasive and safe. Along with the advantages, there are some disadvantages, and work has been carried out to explore the use of silver nanoparticles (SNP) as anticaries agents to shield the teeth from aesthetic damage caused by Silver diamine fluoride. SNPs are identified to have the potential to prevent and inhibit dental caries while not discoloring demineralized dental enamel. SNPs have a greater surface area for interaction with microorganisms than other particles, making them more effective antimicrobial agents. Fluoride combined with SNP solution has a synergistic effect that promotes enamel remineralization while also acting as a bactericidal agent against cariogenic microorganisms. This review aims to bring out the various advantages and disadvantages related to the use of SDF and SNPs to aid in future research.

Current era is witnessing increased dependence on molecular diagnostics for clinical treatment administration. This mandates the researchers to develop methods that possess improvised diagnostic accuracy for the benefit of the patient. Functionalized magnetic nanosystems are emerging as one of the recent techniques that incorporate molecules to provide functional groups that are beneficial for performing bioassays with the advantage of being reusable, reduction in assay time, cost-effective, and safe. The detection of molecular biomarkers plays an important role in the diagnosis of Alzheimer's disease, renal diseases, diabetes, liver diseases, and in various infectious diseases. The addition of magnetic particles enhances the selectivity and adsorption capacity resulting in accurate diagnosis of diseases. Nanobiotechnology would contribute significantly to disease identification and management. This chapter highlights the importance of using functionalized magnetic nanosystems in biomarker-based molecular diagnostics. The applications of this system in the diagnosis of various pathologies are crucial. Various nanodiagnostics have been reviewed that may improve the sensitivity, reduce the patient's waiting period, and overcome the current constraints of molecular diagnostics. The chapter also appraises the applications of biomarker-associated nanodevices and nanosystems. The techniques used for diagnosis will be emphasized with the clinical trials, existing challenges, and imminent perspectives in the utilization of functionalized magnetic nanosystems for molecular biomarker detection. This technology has a promising future in precision and personalized medicine.

The field of vaccination has advanced in leaps and bounds; however, effective and novel vaccines are yet to be developed, especially for diseases like acquired immune deficiency syndrome, malaria and tuberculosis. Lack of immune system stimulation, instability, allergenic potential, multiple shots are some of the shortcomings the vaccines in circulation currently carry. Nanotechnology (NT) is a commanding tool that promises to resolve the abovementioned inadequacies. Nanovaccines (NVs) were developed recently where new drugs can be accommodated through nanoparticle (NP) carriers. The similar nanosize between the nano-scaled materials and pathogens ensures optimal trigger response of the immune system resulting in satisfactory cellular and humoral immunity responses. Targeted delivery of NPs result in enhanced antibody response and improved stability coupled with long-time release addresses the many challenges encountered in vaccine development. This chapter aims to comprehensively evaluate the evolution of NVs and their morphology, carriers used, formulation-characterization and NVs' role in immunotherapy with emphasis on recent advances. Although development of NVs is in the infancy stage and few are in the early clinical phases, we firmly believe this new generation of vaccines has great potential for the prevention and treatment of many diseases.

The field of vaccination has advanced by leaps and bounds; however, effective and novel vaccines are yet to be developed, especially for rapidly spreading coronavirusdisease 2019 (COVID-19)/SARS-CoV2. Many vaccines are created using conventionalapproaches to eradicate COVID-2019, which is presently a global threat. Evenvaccines using nanotechnology are also in the race. Nanotechnology has acceleratedthe evolution of newer vaccines that are safe and highly effective in eradicating theSARS-CoV2. Nanovaccines (NVs) were developed recently where new drugs can beaccommodated through nanoparticle (NP) carriers. The similar nanosize betweenthe nano-scaled materials and pathogens ensures optimal trigger response of theimmune system, resulting in satisfactory cellular and humoral immunity responses.Targeted delivery of NPs results in enhanced antibody response, improved stabilitycoupled with longer duration drug release, and prolonged immunogenic memory.This chapter highlights recently developed antiviral nanovaccines against COVID-19. Although the development of NVs is in the infancy stage and few are in the earlyclinical phases, we firmly believe the newer generation of NVs have greater possibilityof treatment and prevention of bacterial and viral infections.

Nanozymes are becoming more prevalent in nanocatalytic medicine, exhibiting enzyme-like activity with multifunctional nanomaterials. Because of their superior biocompatibility and broad-spectrum antibacterial action, nanozymes are regarded as potent antibacterial agents. The development of nanozymes has demonstrated clear potential to overcome natural enzyme drawbacks such as difficult preparation, ease of denaturation, high cost, and recycling difficulty. Biocatalytic reactions have transformed nanozymes into beneficial antibacterial materials. A comprehensive review of the literature on nanozymes in the treatment of oral diseases such as dental caries, dental pulp diseases, oral ulcers, peri-implantitis, monitoring oral cancer, oral bacteria and ions, and regenerating soft and hard tissues is lacking. As a result, the current review attempts to describe the effective nanozyme-based antibacterial agents for preclinical translations.

Given the present global situation due to COVID-19 crisis, the early diagnosis of the disease cannot be underrated as this helps in preventing the spread of disease and treating the disease at the earliest Though the whole world is behind identifying Severe Acute Respiratory Syndrome Coronavirus 2 and its management, a very convenient, reliable, specific and a sensitive diagnostic test is of utmost need of the hour This paper reviews one such indispensible diagnostic tool © (2020) Society for Biomaterials & Artificial Organs #20041620