Editorial Commentary: The role of periodontal microorganisms in the pathogenesis of myocardial infarction. From PCR techniques to microbiome sequencing

Oral bacteria play a role in various systemic conditions including atheromatous plaques and other cardiovascular diseases [4], and several periodontal pathogens (Porphyromonas gingivalis, Treponema denticola or Fusobacterium nucleatum) have been isolated in samples from cardiovascular patients [5]. [...]it might be conceivable that prolonged inflammation, for example oral inflammation, increases the risk of cardiovascular secondary complications as it further elevates the already high inflammatory burden [6]. At least four basic pathogenic mechanisms have been proposed that involve oral inflammation in the pathogenesis of atherosclerosis: [1] low level bacteremia by which oral bacteria enter the blood stream and invade the arterial wall; [2] systemic inflammation induced by inflammatory mediators released from the sites of the oral inflammation into the blood stream; [3] autoimmunity to host proteins caused by the host immune response to specific components of oral pathogens; [4] pro-atherogenic effects resulting from specific bacterial toxins that are produced by oral pathogenic bacteria. Multiple studies using 16S ribosomal RNA sequencing have identified the taxonomic composition of the subgingival microbiome in both periodontal and healthy individuals [14], and also, on peri-implantitis, a condition that affects the surrounding tissue of dental implants and that has some shared characteristics with periodontitis.