The predominant cultivable microbial population of adult periodontitis.
An extensive characterization of the cultivable microbial population, present in gingival pockets of a selected group of eight patients with periodontal disease, has been performed. The result obtained, from samples collected from six different periodontal sites in each patient, indicate a great prevalence of anaerobic bacteria. It is likely that the presence inside the gingival pockets of anaerobic cocci, to which the rods are capable of a selective coaggregation mechanism, creates conditions favorable to the proliferation of the latter type of bacteria. These findings suggest that the evolution of adult periodontitis is based on a chronic inflammatory stimulus and the necrosis of gingival epithelium caused by the proliferation of the anaerobic rods.