Population-specific dysbiosis of the salivary microbiota in Saudi adults with periodontitis

BACKGROUND: To characterize the dysbiosis of salivary microbiota in Saudi adults with periodontitis and identify potential population-specific microbial signatures. METHODS: Saliva samples were collected from 96 Saudi adults, including 50 patients with periodontitis and 46 control individuals. Microbiota profiling was performed using 16 S rRNA gene sequencing (V3-V4 regions), followed by QIIME2-based bioinformatics and LEfSe analysis to determine diversity and differentially abundant taxa. RESULTS: Significant microbial dysbiosis was observed in the periodontitis group, characterized by higher Shannon diversity and altered community composition. A number of bacterial taxa were enriched specifically in Saudi patients with periodontitis, including Leptotrichia, Acholeplasma, and Rothia dentocariosa-taxa rarely emphasized in global studies. Other enriched taxa included Filifactor, Selenomonas, and Prevotella intermedia. In contrast, control individuals had higher levels of Streptococcus, Granulicatella, and Neisseria oralis. These patterns suggest the presence of regional microbial signatures. CONCLUSIONS: This study reveals distinct salivary microbiota dysbiosis in Saudi adults with periodontitis and highlights unique taxa potentially linked to local environmental, dietary, or genetic factors. These findings support the need for population-specific microbial studies to inform personalized periodontal diagnostics and treatment.