Linking peri-implantitis to microbiome changes in affected implants, healthy implants, and saliva: a cross-sectional...

Area of Science:

• Oral microbiology
• Periodontology
• Metagenomics

Background:

• Dental implant use is increasing, leading to a rise in peri-implant diseases like peri-implantitis (PI).
• Understanding the peri-implant microbiome is crucial for managing PI and ensuring implant success.

Purpose of the Study:

• To investigate the role of the peri-implant microbiome in PI pathogenesis.
• To identify microbial and functional differences between healthy and PI-affected implants.

Main Methods:

• Shotgun metagenomic sequencing of 100 saliva and subgingival biofilm samples from 40 participants.
• Analysis of participants with healthy implants (HI) and those with diagnosed PI-affected implants (PI group).
• Differential ranking analyses to identify discriminative microbial species and functional pathways.

Main Results:

• Specific bacteria (e.g., *Mogibacterium timidum*, *Porphyromonas gingivalis*) were associated with PI, while others (e.g., *Haemophilus parainfluenzae*, *Rothia mucilaginosa*) were linked to healthy implants.
• Functional pathways related to arginine and polyamine biosynthesis correlated with PI, whereas purine/pyrimidine biosynthesis pathways were associated with peri-implant health.
• Microbial and functional profiles of healthy implants in PI-affected patients resembled those of PI-affected implants, and these patterns were also observed in salivary samples.

Conclusions:

• Peri-implant microbiome composition and function differ significantly between healthy and PI-affected sites.
• The presence of PI influences the microbial and functional profiles of even adjacent healthy implants and saliva.
• These findings highlight the complex interplay between the microbiome, host response, and peri-implant health.