Persistence of Helicobacter pylori in the oral cavity after systemic eradication therapy

Aim: The present study aimed to evaluate if the oral cavity of chronic periodontitis patients can harbor Helicobacter pylori after systemic eradication therapy. Materials and Methods: Samples of 30 patients (15 with gingivitis and 15 with chronic periodontitis) positive for H. pylori in the stomach were evaluated. Samples were collected 3 months after triple systemic antibiotic therapy from saliva, microbiota from the dorsum of the tongue, supra- and sub-gingival plaque as well as gastric biopsies. DNA of each sample was extracted by the boiling method and used as a template in polymerase chain reaction with the primers JW22/23. Results: Eighteen patients (60%) harboured H. pylori in their mouths. Five patients (16.6%) were positive in saliva, two (6.6%) on the dorsum of the tongue, nine (30%) in supra-gingival plaque, 14 (46.6%) in sub-gingival plaque and three (10%) in the stomach. There was no statistically significant difference between study groups. Conclusion: Eradication of H. pylori after therapy was more effective for the stomach than for the mouth (p < 0.001). Mouths of patients with gingivitis or with chronic periodontitis, who are positive for H. pylori in their stomachs, may be considered as reservoirs of these bacteria.