Periodontal bacteria in different sampling sites of pericoronitis patients

The study investigated bacteria sampled from the mandibular third molar pericoronitis with the hypothesis that the same species also can be detected in several sites of the oral cavity. Subgingival plaque samples were taken from 41 patients (mean age 23.2 ± 4.2 years), from the third molar pericoronal pocket and from 3 adjacent gingival pockets, from the tongue and saliva. Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), Tan- ne-rella forsythia (T.f.), Prevotella intermedia (P.i.), Pre-votella nigrescens (P.n.), and Treponema denticola (T.d.) were analyzed by qualitative PCR method. All the species analyzed were found in the pericoronitis samples in the following frequency: T.f. 73%, T.d. 68%, P.i. + P.n. 35%, A.a. 5%, and P.g. 5%. Saliva and tongue samples were also highly positive with T.f. (both 76%) and T.d. (saliva 57%, tongue 76%) and better sources for A.a. (saliva 8%, tongue 14%), and P.g. (saliva 14%, tongue 8%) than the pericoronitis pocket. The gingival pocket samples were less frequently positive the further the site in question was from the pericoronitis site. Contrary to earlier observations T.f. was frequently defected in pericoronitis sites. The results emphasize the importance of pericoronitis as a focus of infection.