Prevalence of Helicobacer pylori in saliva and dental plaque related to periodontal disease and gastritis

Helicobacter pylori is a major etiologic factor in the development of gastritis and peptic ulcer disease. Controversially, the oral cavity has been proposed as a reservoir for this bacterium. The aim of the present study was to determine the prevalence of H. pylori in saliva and dental plaque of adult patients affected by periodontal disease, with or without gastrointestinal symptoms, using polymerase chain reaction (PCR). Suitable PCR primers were designed using sequences of H. pylori DNA from the GenBank database. Chronic periodontal disease was clinically and radiologically diagnosed. The samples for PCR were obtained from periodontal pockets. Cell lysate was centrifuged and used as a DNA source for the PCR assays. The PCR products were analyzed in agarose gels and the sizes of the amplicons were estimated by comparison with DNA size markers. Two samples from each patient were obtained, one from dental plaque and the other from saliva. All salivary samples were negative to PCR isolation of H. pylori, while 13.3% of the plaque samples were positive. All patients with positive PCR isolation of H. pylori had been showing gastrointestinal symptoms. PCR isolation of H. pylori was directly related to the depth of the periodontal pocket.   Key words: Periodontitis, gastritis, polymerase chain reaction, Helicobacter pylori.