Effect of Periodontitis and Periodontal Therapy on Oral and Gut Microbiota

Abstract

Mounting evidence indicates that periodontitis-related oral bacteria may contribute to gut microbial dysbiosis. This clinical study aimed to explore the oral-gut microbial signatures associated with periodontitis and to longitudinally evaluate the effect of periodontal treatment on the oral and gut microbial composition. Stool and saliva samples from generalized stage III/IV periodontitis patients (<i>n</i> = 47) were collected and analyzed by 16S ribosomal RNA gene amplicon sequencing, before and 3 mo after steps I to II of periodontal therapy. Periodontally healthy matched subjects (<i>n</i> = 47) were used as controls. Principal component analysis was carried out to identify oral-gut microbial profiles between periodontitis patients at baseline and healthy subjects; periodontitis samples were longitudinally compared before and after treatment. β-Diversity of gut microbial profiles of periodontitis patients before treatment significantly differed from healthy controls (<i>P</i> < 0.001). Periodontal therapy was associated with a significant change in gut microbiota (<i>P</i> < 0.001), with post-treatment microbial profiles similar to healthy volunteers. A higher abundance of <i>Bacteroides</i>, <i>Faecalibacterium</i>, <i>Fusobacterium</i>, and <i>Lachnospiraceae</i> was noted in fecal samples of periodontitis patients at baseline compared to healthy controls. In contrast, <i>Lactobacillus</i> was the only genus more abundant in the latter. Additionally, periodontal therapy led to a parallel reduction in the salivary carriage of periodontal pathobionts, as well as gut <i>Bacteroides</i>, <i>Lachnoclostridium</i>, <i>Lachnospiraceae</i>, <i>Oscillospiraceae</i>, and <i>Ruminococcaceae</i>, to levels similar to healthy controls. Collectively, discriminating oral-gut microbial signatures of periodontitis were found. Periodontal treatment both mitigated oral dysbiosis and altered gut microbial composition, signifying potential broader implications for gastrointestinal health and disease.