Bad breath is mainly treated by cleaning and anti-inflammatory methods, and there are different ways to treat the causes of bad breath. 1, there are residues in the teeth, cavities in the cavities with food residues, and the odor of decay caused by a long period of time without cleaning. If the odor is mild, it can be relieved by brushing the teeth. 2, inflammation in the mouth can also lead to bad breath, such as gingivitis, periodontitis, etc.. The reason is that inflammation will secrete substances and thus odor, no special treatment is needed, as long as the inflammation will be cured bad breath will gradually disappear. 3, physiological bad breath, mainly because of the consumption of smelly food, such as onions, garlic, etc., and smoking or in bed, will also secrete bacteria and lead to bad breath. You need to open your mouth more to breathe more fresh air, and drink vinegar properly to adjust the acid-base balance in the stomach to achieve the purpose of relieving bad breath.4, the stomach with H. pylori infection can also cause bad breath, because the urease secreted by H. pylori can be decomposed into carbon dioxide and ammonia, which is discharged through the esophagus and mouth, of which ammonia is a very bad-smelling gas. You can visit the gastroenterology clinic to check the breath test, if the result is positive, you need anti-H. pylori treatment will relieve bad breath.