Consequences | Aggregatibacter actinomycetemcomitans


If the bacterium Aggregatibacter actinomycetemcomitans is present in the oral flora, gingivitis or periodontitis need not necessarily occur. The bacteria accumulate in the plaque (dental plaque) on the teeth. The plaque consists not only of Aggregatibacter actinomycetemcomitans, but also of many different pathogens that begin to metabolize the products available from food.

If the conditions are favourable and the oral flora is shifted in favour of this bacterium, gingivitis or periodontitis can develop. The first signs are a reddening of the gum line and bleeding gums after brushing the teeth. Brushing the teeth can also be painful and dark discolouration of the gum margins can occur.

At this stage one already speaks of gingivitis. If this is not treated, the bacteria can continue to work their way forward. Gum pockets develop in which all bacteria accumulate.

Aggregatibacter actinomycetemcomitans now begins to attack the periodontium. This consists of the gums, alveolar bone, Desmodont and root cement. The periodontium secures the tooth in its socket and gives it support and stability. If these structures are attacked, the stabilising structures retract and the tooth loses its hold, which can ultimately lead to the loss of the tooth. The above-mentioned processes are not limited to just one tooth, but can occur in various places throughout the oral cavity.


The treatment of gingivitis or periodontitis varies from patient to patient and depends on the extent of the disease. The treatment begins with the removal of plaque and its excrements. This removes all bacteria, including Aggregatibacter actinomycetemcomitans, to prevent further progression of the bacteria.

If the periodontitis is still in its early stages, this can also be done at home, with thorough daily brushing. In most cases, however, professional teeth cleaning is carried out at the dentist. Existing tooth pockets are also removed, as these contain many pathogens as a reservoir.

In order to remove even the last remnants of the bacteria, a mouth rinse, usually based on chlorhexidine, is used. Once this treatment has been successfully completed, the damaged teeth or the degraded bone substance are treated to ensure the best possible care for the dentition. Especially if bone substance has been affected, a complete restoration of the initial situation is usually not possible.

An antibiotic can be used to support the periodontitis therapy. If one wants to proceed against Aggregatibacter actinomycetemcomitans, the removal of the plaque, also under the gingiva (SRP, also called deep scaling or curettage), is usually not sufficient due to the tissue invasiveness, so that amoxicillin is administered as a broad-spectrum antibiotic in addition. The administration of metronidazole, clindamycin, tetracycline is not possible because Aggregatibacter actinomycetemcomitans is resistant to them.


Even if the pathogen is already present in the oral flora, disease does not necessarily occur. However, it is important to take care of your oral cavity to reduce the risk of gingivitis or periodontitis. This includes daily tooth brushing (at least 2x) to remove plaque.

Dental floss, mouthwashes and tongue scrapers can be used as a supplement. It is also important to consume food with a low sugar content so that the bacteria are not given additional nutrients. Regular visits to the dentist are also part of the preventive measures, as he or she can detect and treat possible diseases at an early stage. These visits can also be used to point out possible dental care errors.