Metagenomic Sequencing Reveals Distinct Microbial Community Structures in Healthy and Diseased Oral Microbiota
Abstract Background: Periodontitis and peri-implantitis are common biofilm-mediated infectious diseases affecting teeth and dental implants, and have been considered to be initiated with the adjacent microbial dysbiosis. Study Aim: To further understand the essence of oral microbiota dysbiosis in terms of bacterial interactions, community structure and microbial stability.Methods: We analyzed 64 plaque samples from 34 participants with teeth or implants under different health conditions using metagenomic sequencing. After taxonomical annotation, we computed the core microbiome, analyzed the bacterial co-occurrence networks, and calculated the microbial stability in supra- and sub-gingival plaques from hosts with different health conditions. Result: When inflammation arises, the subgingival communities become less connective and competitive with fewer hub species. In contrast, the supragingival communities tend to be more connective and competitive with a increased number of hub species. Notably, periodontitis and peri-implantitis are associated with significantly increased microbial stability in subgingival plaques. In addition, we also observe similar core bacterial components yet distinct co-occurrence networks and community structures between the healthy and diseased hosts.Conclusion: The findings indicated that the aberrant changes of the bacterial co-occurrence networks and community structures are the essence of dysbiosis in periodontal and peri-implant patients, while breaking the diseased equilibrium and reestablishing healthy equilibrium is crucial for the treatment of periodontitis and peri-implantitis.