Periodontal diseases: microbiological considerations.

The location of plaque-associated gingivitis at the gingival portion of the tooth plays an essential role in its genesis. However, at times local and other host response modifying factors also have an influence. The pathogeny of periodontitis is more complex. The microorganisms that comprise subgingival plaque are capable of acting directly on periodontal tissues or of modifying the host response, whereas the participation of the plaque per se (normal, decreased, or increased) is as decisive as the action of the bacteria themselves in the emergence of the disease. Different types of periodontitis are associated with specific microorganisms. The most periodontopathogenic are A. actinomycetemcomitans, P. gingivalis, and T. forsythensis. Periodontitis as a whole, represent the source of complications such as root caries, endoperiodontal processes and periodontal abscesses. They are associated with various illnesses such as atherosclerosis, diabetes, and respiratory infections, amongst others, as well as pathological oral halitosis. The different modalities of PCR are particularly important in the microbiological diagnosis of periodontitis, although on the negative side of things, it must be pointed out that in vitro sensitivity studies cannot be performed using this technique. First line antibiotic treatment of periodontitis includes amoxicillin/ clavulanic acid, metronidazole (associated or not with amoxicillin) and clindamycin.