The causes of special odor of the mouth are physiologic factors, perioral diseases, nasopharyngeal diseases, and systemic diseases.
1. Physiological factors. Frequent drinking, smoking, garlic will cause bad breath, long-term hunger or fasting lead to a large number of oral bacterial reproduction can also cause bad breath.
2. Perioral diseases. Periodontitis, pericoronitis, dental caries, oral necrotizing inflammation, oral cancer necrosis and other oral diseases lead to a large number of bacterial reproduction in the oral cavity, triggering bad breath.
3. Nasopharyngeal diseases. Atrophic rhinitis, purulent maxillary sinusitis, purulent tonsillitis and so on may also cause severe bad breath.
4. Other systemic diseases. Including chronic gastritis caused by Helicobacter pylori infection, dyspepsia, severe lung infections, lead and mercury and other heavy metal poisoning and other systemic diseases.
When there is unrelieved severe halitosis, it is necessary to consult a doctor in a timely manner to clarify the cause of the disease under the guidance of the doctor and actively treat it.