Microbial etiology of periodontal diseases. Where are we? Where are we going?

Many studies indicate a strong association of Actinobacillus actinomycetemcomitans with localized juvenile periodontitis. Species associated with adult periodontitis include Bacteroides forsythus, Porphyromonas gingivalis, Prevotella intermedia, A. actinomycetemcomitans, and Wolinella recta. Capnocytophaga species may be important in pubertal gingivitis. An unnamed spirochete related to Treponema pallidum has been identified in acute necrotizing ulcerative gingivitis lesions. Species isolated from prepubertal periodontitis, peri-implantitis, pericoronitis, and human immunodeficiency virus gingivitis and periodontitis are similar to those isolated from periodontal and gingival infections. Species identification in combination with clinical characteristics facilitates periodontal diagnosis. DNA probes, immunoassays, and benzoyl-arginine naphthylamide reactivity methods can be used to indicate putative pathogens in plaque samples. Microbial identification aids in antibiotic selection and planning a treatment regimen.