Silver Nanoparticles and Their Therapeutic Applications in Endodontics: A Narrative Review

Abstract

The efficient elimination of microorganisms and their byproducts from infected root canals is compromised by the limitations in conventional root canal disinfection strategies and antimicrobials. Silver nanoparticles (AgNPs) are advantageous for root canal disinfection, mainly due to their wide-spectrum anti-microbial activity. Compared to other commonly used nanoparticulate antibacterials, AgNPs have acceptable antibacterial properties and relatively low cytotoxicity. Owing to their nano-scale, AgNPs penetrate deeper into the complexities of the root canal systems and dentinal tubules, as well as enhancing the antibacterial properties of endodontic irrigants and sealers. AgNPs gradually increase the dentin hardness in endodontically treated teeth and promote antibacterial properties when used as a carrier for intracanal medication. The unique properties of AgNPs make them an ideal additive for different endodontic biomaterials. However, the possible side effects of AgNPs, such as cytotoxicity and tooth discoloration potential, merits further research.

Application of Nanomaterials in Endodontics

“…Silver NPs (Ag NPs) can cause damage to bacterial cells walls, and also penetrate to reach the cytoplasm, where they interact with biomolecules containing sulfur and phosphorus, such as nucleic acids [ 4 ]. In addition, Ag NPs release Ag ions that further disrupt bacterial metabolic activity [ 4 ]. Ag NPs can be delivered in various vehicles, including hydroxyethyl cellulose polymer, polyethylene glycol, and carbomer polymer.…”

“…Ag NPs can be delivered in various vehicles, including hydroxyethyl cellulose polymer, polyethylene glycol, and carbomer polymer. When assessed for antibacterial effects against S. mutans, E. faecalis , Escherichia coli , Pseudomonas aeruginosa , and Staphylococcus aureus, the hydroxyethyl cellulose polymer gel gave the best handling characteristics and had superior performance as an antibacterial agent [ 4 ]. The surface charge (zeta potential) of Ag NPs affects their antibacterial activity and their interactions with human cells.…”

“…Nanotechnology has experienced notable advancements, capturing the attention of various scientific disciplines including dentistry [ 1 ]. In endodontics, the application of nanomaterials is reflected in the growing body of research literature [ 2 – 4 ]. As for the definition of nanomaterials, the European Commission recommends an updated definition, proposing that nanomaterials encompass solid particles of natural, incidental, or manufactured origin and at least 50% of their number-based size distribution falls within the range of 1 to 100 nm [ 5 ].…”

Green Biofabrication of Silver Nanoparticles of Potential Synergistic Activity with Antibacterial and Antifungal Agents against Some Nosocomial Pathogens

“…On the other hand, the biogenic AgNPs showed synergistic activity with the antifungal drug clotrimazole, disrupting the synthesis of ergosterol, the primary component of fungal cells' membranes, depleting it, and replacing it with the aberrant sterol species 14-methylsterol, which then impairs membrane fluidity and permeability [99]. Additionally, the biogenic AgNPs exhibited an antifungal mode of action through interactions with DNA and protein, which disrupted these molecules and caused cell death, which then worked in a synergistic way with clotrimazole against C. albicans strain [100].…”

Actividad antibacteriana y biocompatibilidad de nanopartículas funcionalizadas como desinfección en neoterapias endodónticas.

“…Siendo el primer reporte del uso de CuNPs funcionalizadas como una posible alternativa de desinfección en endodoncia (Raura et al, 2020). El uso de AgNPs ha sido más ampliamente reportado, pero no funcionalizadas (Afkhami et al, 2023). Este proceso de funcionalización utilizando matrices poliméricas, pueden proporcionar mejoras en las propiedades a las NPs, por ejemplo, disminuir su toxicidad al utilizar polímeros inocuos y biocompatibles, mejorar la actividad antibacteriana de las NPs, al permitir la obtención de NPs de menor tamaño, distintas formas entre otros (Veerapandian & Yun, 2011).…”