If you have bad breath inside your mouth, the most common solution is to go to the hospital to clean your teeth. Because 80% of bad breath is caused by poor oral hygiene, most of them have dental calculus, which stimulates the gums and makes them appear red, swollen and bleeding, accompanied by bad breath, and the bad breath will disappear after scaling. In addition to bad breath caused by poor oral hygiene, there may also be reflux esophagitis and crypt tonsillitis. If bad breath is caused by these two causes, the solution is to treat both diseases. Reflux esophagitis should be treated with medication, and crypt tonsillitis should be treated with surgery to remove the tonsils, and after the inflammation is controlled and the tonsils are removed, the bad breath will disappear.