To investigate the correlation of Helicobacter pylori infection in the oral cavity and stomach, and correlation of Helicobacter pylori infection in the oral cavity and periodontitis.

120 patients with chronic gastric diseases received ¹³C-urea breath test, Hp saliva test and periodontal examination. The correlation of Helicobacter pylori infection in the oral cavity and stomach, and correlation of Helicobacter pylori infection in the oral cavity and periodontitis were analyzed.

The experiments showed that the positive rate of Hp in the oral cavity was 87.7% in stomach-Hp-positive patients, while the positive rate of Hp in the oral cavity was only 42.6% in stomach-Hp-negative patients, which was significantly lower (P<0.001). The positive rate of Hp in the oral cavity in patients with normal periodontium, mild periodontitis, moderate periodontitis and severe periodontitis were 45.5%, 55.3%, 81.5% and 82.4% separately, and the difference was statistically significant (P<0.01).

Hp infection in the oral cavity is closely related to its infection in the stomach, and is also related to the severity of periodontitis.