Most dental infections are caused by anaerobic bacteria. The species most frequently involved are: Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythensis, Campylobacter rectus, Eubacterium species, Fusobacterium nucleatum and Peptostreptococcus micros.

The mouth, like all surfaces of the body, is colonized by a bacterial flora, called commensal, whose role is to protect them against invasions by pathogens.

This flora is not pathogenic but can become so in certain circumstances, when bacteria are moved to areas which are usually sterile (following an injury, surgery, etc.) or when they multiply on the surface of a foreign body ...

Two types of flora coexist, the supragingival flora and the subgingival flora, living in perfect balance. If this balance changes, a risk of oral pathologies may appear. The supragingival flora is then at the origin of the acid demineralization of dental hard tissues, while the subgingival flora is responsible for pathologies of the periodontium.

Dental caries and periodontal disease are infectious diseases that occur when there is an imbalance in bacterial activity in the oral ecosystem. But in this type of infection, antibiotics are reserved for infrequent situations, the treatment of infectious foci is most often non-drug. Oral hygiene is fundamental in the prevention of infections in oral medicine.

Could good oral hygiene prevent heart problems? There is a growing body of evidence that there is a link between the presence of certain bacteria in dental plaque and the risk of developing heart problems. Researchers have looked at people with periodontal disease. They found more periodontal bacteria in the dental plaque of people who had already had a stroke (heart attack). They also found these same bacteria in the lining of their heart arteries. They suspect that the inflammation in the gums causes the surrounding blood vessels to dilate. The walls of the swollen vessels would then become more permeable and allow bacteria to pass into the bloodstream and travel to other parts of the body where they continue to cause significant damage. By implanting in the walls of the arteries, they cause inflammation there. However, it is thought that inflammation of the blood vessels plays a big role in the process leading to heart problems.