Objective: To analyse the subgingival microbiota of Stage I/II periodontitis, gingivitis with different degrees of severity, and periodontal health in subjects in a Chinese young adult population.
Methods: Subgingival plaque samples were collected from 15 Stage I/II periodontitis patients, 38 gingivitis patients and 15 periodontally healthy individuals, all aged from 18 to 21 years. Gingivitis patients were divided into two subgroups according to the Bleeding Index (BI) of their sampled teeth: gingivitis with above median BI (G-HBI) and below median BI (G-LBI). The subgingival plaque samples were collected from teeth 16, 26, 36, 46, 11 and 31 according to FDI notation. The V3-V4 region of the 16S rRNA gene of all the samples was sequenced and analysed.
Results: The Stage I/II periodontitis, gingivitis and periodontal health groups showed distinct subgingival microbiota profiles. When the gingivitis patients were stratified into two subgroups, the community structure of G-HBI showed no significant difference from early-stage periodontitis, but differed from G-LBI and the healthy group. Most periodontitis-related taxa were most abundant in Stage I/II periodontitis, followed by G-HBI, G-LBI and the periodontally healthy group. Porphyromonas gingivalis, Filifactor alocis, Tannerella forsythia, Saccharibacteria TM7 G-5 356, Lachnospiraceae G-8 500, Peptostreptococcaceae spp. and Syntrophomonadaceae VIIIG-1 435 were associated with Stage I/II periodontitis. Porphyromonas 275, Leptotrichia 417 and Saccharibacteria TM7 G-2 350 were associated with gingivitis. Porphyromonas gingivalis was significantly more abundant in G-HBI than in G-LBI.
Conclusion: Within the limitations of this preliminary study, gingivitis and early-stage periodontitis were associated with an increased degree of dysbiosis in the subgingival microbiota in a Chinese young adult population.