Mucoadhesive silver nanoparticle-based local drug delivery system for peri-implantitis management in COVID-19 era. Part 1: antimicrobial and safety in-vitro analysis

Background: Pseudomonas aeruginosa, a major respiratory pathogen, has been isolated from peri-implant sites and is associated with dental implant failure. This in-vitro study (part 1) aimed to fabricate a novel mucoadhesive silver nanoparticle-based local drug delivery chip, evaluate its antimicrobial efficacy against P. aeruginosa, and its safety for the treatment of peri-implantitis.

Materials and methods: Silver nanoparticles were synthesized and characterized using a transmission electron microscope (TEM). The local drug delivery chip was fabricated using gelatin, glycerol, silver nanoparticle solution (2.5 μg/ml, 5 μg/ml, 7.5 μg/ml, and 10 μg/ml), glutaraldehyde, and sodium alginate solution. These chips were evaluated for physical parameters, effect on viability of murine macrophage cell line J774A.1, and antimicrobial activity (using Kirby-Bauer disc diffusion method with 18 h incubation period) against P. aeruginosa ATCC 27853.

Results: Silver nanoparticle antimicrobial chip exhibited dimensions of 4 mm × 5 mm x 0.4 mm, 5.8 mg weight, pH 5-6, folding endurance 1.04, and one-year stability. P. aeruginosa was susceptible to ≥ 7.5 μg/ml concentration of silver nanoparticles (spherical shape with particle size ranging from 10 to 100 nm). Murine macrophage cells exhibited 93% viability after 24 h incubation with silver nanoparticle chips.

Conclusion: The novel silver nanoparticle chip showed dimensional stability, minimal effect on murine macrophage cell viability, and significant antimicrobial activity against P. aeruginosa. With the further establishment of its effective dosage and safety, this chip could be used as an adjunct to mechanical debridement (as a non-aerosol generating procedure) in treating peri-implantitis, especially during the ongoing coronavirus disease 2019 (COVID-19) pandemic.