Halitosis can generally be divided into two major categories: simple and secondary. Simple halitosis is often caused by poor oral hygiene or bad living habits, such as not brushing teeth and rinsing mouth regularly, excessive dental calculus, neglecting the cleaning of dentures, loving eating snacks, etc., all of which can lead to halitosis.
After middle age, the reduction in saliva secretion decreases the self-cleaning function of the mouth, so middle-aged and elderly people are more likely to have halitosis. In addition, heavy smokers often have a smoky smell from their mouths and noses, which also falls into this category.
There are many causes of secondary halitosis, common ones include:
[Oral Diseases] Such as alveolar abscess, caries, gingivitis, pulpitis, suppurative tonsillitis, and sialadenitis, etc., which can cause putrid halitosis.
[Diseases of Organs Near the Mouth] Such as nasal and nasopharyngeal diseases like suppurative maxillary sinusitis, atrophic rhinitis, etc., which can also lead to halitosis.
[Gastrointestinal Diseases] Patients with chronic gastritis and duodenal ulcers often have an acidic odor in their mouths. Patients with pyloric obstruction and advanced gastric cancer often have a rotten egg smell halitosis. Severe constipation and intestinal obstruction patients often have a fecal odor halitosis.
[Respiratory System Diseases] Patients with lung abscesses often have a putrid acid halitosis, foul smell. Patients with tuberculosis hemoptysis and bronchiectasis hemoptysis often have a bloody halitosis. Advanced lung cancer patients often have a rotten fishy smell in their mouths and breath.
[Others] Diabetic patients may have a rotten apple or ketone smell in their mouths. Uremia patients may have an ammonia smell in their mouths and breath. Liver coma patients may have a liver smell. Hemophilia patients may have a blood smell in their mouths.