New Insights into the Pathogenesis of Periodontal Diseases

<jats:p> Throughout our lives, we continuously encounter micro-organisms that range from those essential for health, to those causing diseases. The oral cavity is permanently colonized by micro-organisms and our immune system has a challenging role in maintaining oral homeostasis by balancing its responses to this unique microbiota, while preserving the structural integrity of oral tissues. This article discusses relationships between oral microbial community structure and activity, specifically addressing the role of low-abundance microbial species and their interplay with the host immune system, in view of the pathogenesis of dental plaque-induced periodontal conditions. </jats:p><jats:p> CPD/Clinical Relevance: The knowledge of periodontal disease pathogenesis is critical for understanding periodontal risk assessment and designing effective, patient-centred treatment options. </jats:p>