Salivary microbiome

Unlike the uterine, placental and vaginal microbiomes, the types of organisms in the salivary microbiota remain relatively constant. There is no difference between populations of microbes based upon gender, age, diet, obesity, alcohol intake, race, or tobacco use. The salivary microbiome characteristically remains stable over a lifetime. One study suggests sharing an environment (e.g., living together) may influence the salivary microbiome more than genetic components. While the salivary microbiome shows stability, the broader oral microbiome can be influenced by various factors. A number of elements, including diet, dental hygiene, age, underlying medical conditions, and the use of antibiotics, as well as lifestyle choices such as smoking and alcohol consumption, and physiological changes such as pregnancy, the menstrual cycle, and menopause, can exert an influence on the composition of the oral microbiome. == Genetic markers and diagnostic testing ==

"There is high diversity in the salivary microbiome within and between individuals, but little geographic structure. Overall, ~13.5% of the total variance in the composition of genera is due to differences among individuals, which is remarkably similar to the fraction of the total variance in neutral genetic markers that can be attributed to differences among human populations." The sugar concentration in salivary secretions can vary. Blood sugar levels are reflected in salivary gland secretions. High salivary glucose (HSG) levels are a glucose concentration ≥ 1.0 mg/d, n = 175) and those with low salivary glucose (LSG) levels are < 0.1 mg/dL n = 2,537). Salivary gland secretions containing high levels of sugar change the oral microbiome and contributes to an environment that is conductive to the formation of dental caries and gingivitis. ==Salivary glands==

: 1.parotid, 2.submandibular, 3.sublingual. Organisms of the salivary microbiome reside in the three major salivary glands: parotid, submandibular, and sublingual. These glands secrete electrolytes, proteins, genetic material, polysaccharides, and other molecules. Most of these substances enter the salivary gland acinus and duct system from surrounding capillaries via the intervening tissue fluid, although some substances are produced within the glands themselves. The level of each salivary component varies considerably depending on the health status of the individual and the presence of pathogenic and commensal organisms. == References ==