['The influence of gastric Helicobacter pylori infection on the development of oral pathoses remains unclear. The aim of this study is to examine the influence of gastric H. pylori infection on occurrence of halitosis and coated tongue.', 'Ninety-eight patients with dyspepsia were included in the study and their salivary samples and gastric biopsies were analyzed for the presence of H. pylori by Nested-PCR. Halitosis and coated tongue were assessed at the initial examination and 3 months after systemic eradication therapy against H. pylori.', 'Gastric biopsies of 66 patients were positive for H. pylori. Only one saliva sample was H. pylori positive. At initial examination, halitosis was observed in 20 patients (30.3%) out of 66 who had gastric H. pylori infection and in only 3 patients (9.4%) out of 32 without H. pylori infection (p = 0.0236). Coated tongue was diagnosed in 18 (27.2%) patients with the infection compared to only 2 (6.25%) patients negative for gastric H. pylori (p = 0.0164). Patients with gastric infection were treated with the triple eradication therapy (Amoxicillin, Clarythromycin, Pantoprazol) and their gastric biopsies and oral status were examined 3 months later. Halitosis was significantly more prevalent in the group of patients with persistent H. pylori infection (42.1%) compared to only 6.4% of patients in the group where infection was successfully eradicated (p = 0.0012). Coated tongue was diagnosed in 47.4% of patients where H. pylori was still present after eradication therapy and in only 6.4% where eradication succeeded (p = 0.0003).'] Does eradication of gastric Helicobacter pylori ameliorate halitosis and tongue coating?