Research on Host–Oral Bacteria Interactions in Periodontal Pathogenesis

Dear Colleagues,

Periodontitis is a chronic infectious disease characterized by an exacerbated inflammatory response and progressive loss of tooth-supporting tissue. Porphyromonas gingivalis is a periodontopathogen bacterium implicated as a major etiological agent in periodontitis which expresses a diverse array of virulence factors, such as gingipains, lipopolysaccharides, fimbriae, and outer membrane vesicles, that modulate host immune signaling, disrupt epithelial barriers, and facilitate immune evasion. Additionally, cytokines are involved in the initiation and progression of periodontal disease, and although cytokine promotes the elimination of bacteria, overproduction of pro-inflammatory cytokines may participate directly in periodontal breakdown, such as in collagen periodontal attachment loss and alveolar bone resorption disease. Periodontitis is a multifactorial inflammatory condition related to complex molecular-level host–oral bacteria interactions. The shift from a symbiotic commensal microbiota to a dysbiotic pathogenic community is mediated by changes in bacterial gene expression, metabolic activity, and interspecies signaling that promote virulence and persistence within the subgingival niche. Subgingival biofilm formation involves coordinated molecular processes, including bacterial adhesion, quorum sensing, extracellular matrix production, and increased resistance to antimicrobial agents and host defenses, with dysregulated host–microbiota interactions promoting chronic inflammation, osteoclast activation via the RANK/RANKL/OPG axis, and progressive alveolar bone loss. Host genetic and epigenetic factors further influence disease susceptibility and progression, while the oral microbiome beyond bacteria—including fungi, viruses, and bacteriophages—also contributes to microbial community dynamics and host responses. Advances in molecular, in vitro, and in vivo models, together with omics-based approaches, are enhancing our understanding of periodontal pathogenesis and supporting the development of innovative, targeted therapeutic strategies.

This Special Issue aims to understand the host–bacteria relationship in periodontal disease from several perspectives, including the transition from a commensal to a pathogenic microbiota; synergistic and antagonistic interactions among oral bacteria; and the presence of subgingival biofilms, including their structure, maturation, and resistance. Relevant characterizations of the main periodontopathogenic bacterium, Porphyromonas gingivalis, are also welcome, alongside explorations of bacterial virulence factors, host innate immune response in periodontitis, immune evasion mechanisms, host–microbiota interactions and periodontal tissue destruction, the influence of host-related factors, and the role of the oral microbiome beyond bacteria. Submissions presenting in vitro and in vivo models of host–bacteria interactions, innovative strategies for the treatment of periodontitis, and the challenges in translating basic research findings into clinical practice are encouraged. The objective of this Special Issue is to present a cutting-edge platform for research and critical reviews that elucidate the molecular, cellular, and ecological mechanisms governing host–oral bacteria interactions in periodontal disease. We aim to integrate microbiological and immunological perspectives to better understand how dysbiosis and host responses drive disease initiation and progression.

Dr. Ana María Fernández Presas
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the Special Issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 250 words) can be sent to the Editorial Office for assessment.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-anonymized peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.