a. Post Nasal Drip
Post nasal drip is an interior nasal discharge that can feed the bacteria in the mouth that are associated with the production of the smell. The bacteria tend to be on the back of the mouth, which means that the nasal drip will fall on the microorganisms which would worsen the problem. The contents of the nasal drip contain proteins, which form smelly compounds.
Sinusitis is a condition where the mucus lining of the sinuses become irritated, infected or inflamed, and start to produce excessive amounts of mucus. It can be due to a viral infection, as in the case of colds, or allergies. The mucus gets stuck within these nasal passages and starts to attract bacteria, which love dark, damp places. These bacteria will multiply and excrete waste products that contain noxious sulfur compounds causing halitosis.
Polyps are mostly nonmalignant growths or tumors arising from the membrane lining of the nose, often causing obstruction and congestion. Polyps can also block drainage, creating stagnant secretions that lead to an infection and cause sinusitis. The blockage makes the bacteria to proliferate causing bb.
d. Foreign Object
BB could be the result of a blockage or obstruction in the nasal passages that is preventing normal airflow and drainage, or it could be coming from small parts or food being lodged in the nose, where it can gradually deteriorate and cause bad smells. A sign of this would be a discharge from the nose. Occasionally undigested food gets lodged in the sinuses when an individual vomits.
An open mouth leads to loss of moisture on the tongue and palate. When our mouth is dry, saliva production decreases, leaving the mouth's natural ability to clean itself impaired and giving the opportunity to odorous bacteria to increase.
Ozena, or atrophic rhinitis, is a disease of the nose where the bony ridges and mucous membranes inside are wasting away. Nasal crusting, discharge, and a very bad smell are other usual symptoms of ozena. Ozena maybe a consequence of a long period of nasal swelling.
Syphilis of the nose may cause halitosis through a gumma formation (nodule, tumor) that usually affects the nasal bones and tissues in the area. As result there can be necrosis with an offensive smell.
Rhinoscleroma is a chronic granulomatous condition of the nose and other structures of the upper airways. The deforming masses of tissue can become malodorus.
Adenoiditis is an inflammation of the adenoids due to viral and bacterial infection and allergy. Adenoids are a mass of lymphoid tissue located at the very back of the nose. It may produce bad breath due to the production of a purulent discharge or to an obstruction of the nasal airways forcing the person to breath through the mouth.