Bad breath is viewed as a social taboo and those affected may be stigmatized. People in the United States spend more than $1 billion per year on mouthwash to treat it. Signs and symptoms
Bad breath is when a noticeably unpleasant odour is believed to be present on the breath. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder. Causes
Mouth
In about 90% of genuine halitosis cases, the origin of the odour is in the mouth itself. This is known as intra-oral halitosis, oral malodour or oral halitosis. The most common causes are odour producing biofilm on the back of the tongue or other areas of the mouth due to poor oral hygiene. This biofilm results in the production of high levels of foul odours. The odours are produced mainly due to the breakdown of proteins into individual amino acids, followed by the further breakdown of certain amino acids to produce detectable foul gases. Volatile sulfur compounds are associated with oral malodour levels, and usually decrease following successful treatment. Other parts of the mouth may also contribute to the overall odour, but are not as common as the back of the tongue. These locations are, in order of descending prevalence, inter-dental and sub-gingival niches, faulty dental work, food-impaction areas in between the teeth, abscesses, and unclean dentures. Oral based lesions caused by viral infections like herpes simplex and HPV may also contribute to bad breath.
Bacteria are invisible to the naked eye, and degrees of white tongue coating are present in most people with and without halitosis. A visible white tongue coating does not always equal the back of the tongue as an origin of halitosis, however a "white tongue" is thought to be a sign of halitosis. In oral medicine generally, a white tongue is considered a sign of several medical conditions. Patients with periodontal disease were shown to have sixfold prevalence of tongue coating compared with normal subjects. Halitosis patients were also shown to have significantly higher bacterial loads in this region compared to individuals without halitosis. Gums
Gingival crevices are the small grooves between teeth and gums, and they are present in health, although they may become inflamed when gingivitis is present. The difference between a gingival crevice and periodontal pocket is that former is <3mm in depth and the latter is >3mm. Periodontal pockets usually accompany periodontal disease (gum disease). There is some controversy over the role of periodontal diseases in causing bad breath. However, advanced periodontal disease is a common cause of severe halitosis. People with uncontrolled diabetes are more prone to have multiple gingival and periodontal abscess. Their gums are evident with large pockets, where pus accumulation occurs. This nidus of infection can be a potential source for bad breath. Removal of the subgingival calculus (i.e. tartar or hard plaque) and friable tissue has been shown to improve mouth odour considerably.