People who have bad teeth usually have bad stomachs. Why is that? We know that if the teeth are unhealthy, with dental caries and periodontitis, chewing function is poor, eating is like swallowing dates, food is not fully chewed, it will increase the burden on the stomach, nutrients are not fully absorbed will cause gastric disease. Is there any other connection? Recent scientific studies have deepened the understanding of the relationship between teeth and gastric diseases. As the saying goes, “nine out of ten people have gastritis,” and gastritis and gastric ulcers are common chronic diseases that are prone to recurrence and difficult to cure. In recent years, research findings have shown that they are caused by Helicobacter pylori (Hp) infection. Under scanning electron microscopy, H. pylori is shaped like a group of small, fat, white, non-silkworm-like things, its body is mildly S-shaped curved, with several sheathed flagella at one end. In 1995, China’s malignant tumor cause of death survey reported that the mortality rate of gastric cancer still ranks first among the total causes of cancer deaths. The World Health Organization (WHO) has listed Hp as the first cause of gastric cancer. Experts estimate that 50% of gastric cancers in China are related to Hp infection. Medical doctors have further explored: from where does H. pylori enter the stomach? It was only when experts cultured H. pylori from the patient’s mouth with the exact same category, type, and strain of H. pylori present in the stomach that definitive evidence was found: the “culprit” of these gastric diseases, H. pylori, actually originated from the mouth! The presence of H. pylori in the pus of periodontal disease, which is common among middle-aged and elderly people, is significant. Dental plaque also has a large number of H. pylori, when the body’s resistance is low, with saliva or food swallowed in the stomach of H. pylori will “make waves”, leading to the occurrence and recurrence of gastric disease. Therefore, it is important to keep your teeth healthy. If patients can adhere to good oral hygiene and health care habits while treating gastric disease, master the correct brushing method, brush teeth in the morning and evening, rinse mouth after meals, and change toothbrushes frequently (because there is also a large amount of Hp hidden in the contaminated toothbrush), and try to remove the hidden problem of H. pylori in oral lesions and old toothbrushes, it will be of great help to the treatment of gastric disease. The University of Oklahoma College of Dentistry, USA, Tom K. Glass, a professor at the University of Oklahoma College of Dentistry, has conducted a study on 100 chronic gastric patients. Prof. Tom Glass of the University of Oklahoma College of Dentistry did the above-mentioned trial on 100 volunteers with chronic gastric disease, and after 1 year, there was no 1 case of gastric disease recurrence, which is remarkable. For patients who wear dentures, brushing here also includes cleaning of dentures. Keep the denture clean and hygienic, to do after each meal brush teeth cleaning, night sleep to take off, the morning scrubbing clean and then wear in the mouth. Dentures should not be scalded with hot water, and do not soak with alcohol or other medicinal solutions to avoid deformation and deterioration of dentures. Before going to bed at night, take off the dentures, rinse them with water and soak them in cold water, so that the oral tissues get sufficient rest and keep them clean. Daily cleaning of dentures will also prevent the occurrence of oral Helicobacter pylori, thereby reducing the incidence of gastric disease.