# Effects of silver nanoparticle coating on peri-implant mucosa and microbiome

## TL;DR

This study shows that coating dental implants with silver nanoparticles can improve gum health and reduce bad odors by changing the local bacteria.

## Contribution

The study demonstrates that AgNP coatings alter the peri-implant microbiome and improve clinical outcomes.

## Key findings

- AgNP coating significantly reduced modified gingival index values compared to the control group.
- The experimental group showed a shift in odor patterns and microbiome composition, with increased Neisseria oralis and Ottowia species.
- The coating decreased the abundance of harmful bacteria like Veillonella parvula and Tannerella forsythia.

## Abstract

We conducted a study to investigate whether a silver nanoparticle (AgNP) coating on the surface of an implant superstructure could alter the microbiome of peri-implant tissues and to determine whether the AgNP coating would result in an improvement of gingival conditions and be effective in suppressing malodors.

We conducted a single-blind, parallel group comparative study in 19 patients undergoing implant maintenance. The 9 patients in the experimental group were treated by applying an AgNP coating after ultrasonic cleaning of the implant superstructure. Ultrasonic cleaning alone was performed on the 10 patients in the control group. The efficacy of the AgNP coating was evaluated by the following procedures conducted at baseline and after 3 months: measuring the modified gingival index (mGI), analyzing odor patterns through organoleptic test and olfactometric device readings of the implant superstructure, and determining the composition of the peri-implant microbiome.Registry: the Ethics Committee for Clinical Research of Fukuoka Gakuen, TRN: 530, Registration date: 30 March 2022.

The mGI values in the intervention group were significantly decreased (p = 0.043) than in the control group. In the organoleptic test, no significant intergroup differences were found in the sensory scores, but the sensory comments indicated that the odor type had changed in the experimental group. Principal component analysis (PCA) of the odor patterns at baseline and after 3 months revealed a change in the axis of the first principal component in the experimental group, but no change in the control group. A comparison of the peri-implant microbiome composition between the experimental group and the control group after three months revealed that the experimental group exhibited a significantly higher relative abundance of Neisseria oralis and Ottowia species, and a significantly lower relative abundance of Veillonella parvula, Fretibacterium fastidiosum, and Tannerella forsythia than the control group.

These findings suggest that the AgNP coating of the implant superstructure changed the composition of the microbiome, and that such a change may improve gingival conditions and provide a deodorizing effect.