If you suffer from bad breath, you can consider going to the following three departments for examination and treatment: First, it is recommended to go to the stomatology department because more than 80% of bad breath is directly related to poor oral hygiene, such as the presence of dental calculus in the mouth, gingivitis, periodontitis or decay, rotten roots are not removed, the bacterial content in the mouth will be particularly high, bacteria and their secretions will produce smelly substances, and bad breath will occur. Secondly, you can go to the ear, nose and throat department, there are some diseases in the ear, nose and throat department can also cause bad breath, such as chronic crypt tonsillitis, these patients have a very large number of bacterial plugs in the tonsillar crypt, dislodged within the mouth will have a distinct odor, if in the acute stage there will also be bacterial plugs exposed in the throat, will be with the breath, the mouth emits bad breath. In addition to this, you can also go to the gastroenterology department for examination, some patients with reflux esophagitis will also have bad breath.