Oral Microbiome Dysbiosis: Periodontitis Links to Systemic Diseases

Dynamics and Composition of the Oral MicrobiotaColonization begins moments after birth, driven by maternal contact and surroundings. 1,3,8The microbiome matures across life phases, transforming notably with teething-which adds durable enamel-and hormonal changes such as puberty or pregnancy. 10,11he structure of the oral microbial community is dominated by seven key bacterial phyla, including Actinomycota, Bacteroidota, Bacillota, Fusobacteriota, Pseudomonadota, Saccharibacteria (TM7), and Spirochaetota. 3,10 IntroductIon Oral Cavity as a Systemic GatewayThe oral microbiome represents a complex microbial environment in humans, encompassing more than 700 distinct bacterial species in addition to fungi, archaea, protozoa, and viral components. [1][2]2][3][4] It ranks as the body's second-most populous microbial population, trailing only the gut. 2,5These microbes settle into specialized sites, such as teeth, gingival crevices, the tongue, and cheek linings, covering roughly 500 square centimeters of surface. 3,6,7In health, this community thrives in eubiosis-a stable symbiotic state upheld by mutual benefits, rivalry, and microbial conflicts. 8,9This harmony supports not just oral stability but overall health. 10Yet it remains delicate, vulnerable to disturbances from inadequate hygiene, sugary diets, smoking, alcohol, and underlying diseases. 10Such imbalances spark dysbiosis, fostering harmful microbial shifts that fuel ongoing inflammation. 1,3Periodontitis, a persistent inflammatory infection born from this dysbiosis, now stands as a "low-grade systemic condition." 7,11Far from confined to the mouth, its pathogens and inflammatory products travel via bloodstream or other routes, forging clear ties to heart disease, diabetes, brain disorders, and cancers.