Stage-Associated Subgingival Dysbiosis Across the Periodontal Disease Spectrum in a Thai Cohort

This cross-sectional study aimed to investigate the subgingival microbiota and predict functional profiles across the 2018 EFP/AAP periodontal disease spectrum in a Thai clinical cohort.

Subgingival plaque from 100 participants (gingivitis, n = 30; Stage II-IV periodontitis, n = 70) was analysed by 16S rRNA gene sequencing with taxonomic assignment using the Human Oral Microbiome Database.

Peptostreptococcaceae-related taxa, Dialister pneumosintes, Shuttleworthia satelles, Prevotella sp. HMT-304, and Bacteroidetes [G-3] bacterium HMT-280 were recurrently identified across differential abundance and penalised regression analyses. Penalised regression models showed limited stage-discriminative performance (multinomial AUC 0.68-0.78), with gingivitis achieving the highest classification accuracy (63%) and Stage IV the lowest, consistent with overlapping microbial profiles across stages. Nonetheless, some stage-enriched taxa included Campylobacter species in Stage III and Porphyromonas gingivalis with Odoribacter bacterium HMT-516 in Stage IV. Stage-enriched taxa correlated with anaerobic fermentation pathways, while co-occurrence networks became less dense but broader across stages.

Stage-associated microbiome shifts were detectable using a gingivitis reference group, with a disease-associated core and accompanying anaerobic functional enrichment. The findings suggest that subgingival dysbiosis across periodontitis stages does not follow a simple linear trajectory and that clinical stage is not determined by microbiome composition alone.