Emerging Periodontal Pathogens

Periodontitis is now understood as a polymicrobial dysbiotic disease resulting from complex interactions between the subgingival microbiome and the host immune response. Earlier concepts focused on a limited number of pathogens, but the work of Sigmund Socransky established the importance of microbial complexes, particularly the red complex, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola in disease progression.Advances in molecular techniques, especially next-generation sequencing, have expanded our understanding of the periodontal microbiome and led to the identification of newer periodontal pathogens. These include organisms such as Filifactor alocis, Enterococcus faecalis, Staphylococcus aureus, and Escherichia coli, which may act as pathobionts, contributing to disease under favorable environmental conditions. The newer periodontal pathogens have broadened the understanding of periodontal disease from a specific infection model to a complex, community-driven process. This evolving knowledge supports the development of targeted, personalized, and microbiome-based therapeutic approaches in contemporary periodontology.