Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder.The concerns of bad breath may be divided into genuine and non-genuine cases. Of those who have genuine bad breath, about 85% of cases come from inside the mouth. The remaining cases are believed to be due to disorders in the nose, sinuses, throat, lungs, esophagus, or stomach.
Rarely, bad breath can be due to an underlying medical condition such as liver failure or ketoacidosis. Non-genuine cases occur when someone feels they have bad breath but someone else cannot detect it. This is estimated to make up between 5% and 72% of cases.The treatment depends on the underlying cause. Initial efforts may include tongue cleaning, mouthwash, and flossing. Tentative evidence supports the use of mouthwash containing chlorhexidine or cetylpyridinium chloride. While there is tentative evidence of benefit from the use of a tongue cleaner it is insufficient to draw clear conclusions.
Treating underlying disease such as gum disease, tooth decay, or gastroesophageal reflux disease may help. Counselling may be useful in those who falsely believe that they have bad breath.Estimated rates of bad breath vary from 6% to 50% of the population. Concern about bad breath is the third most common reason people seek dental care, after tooth decay and gum disease. It is believed to become more common as people age.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 the condition.
The most common causes are odor producing biofilm on the back of the tongue, below the gumline, and in the pockets created by gum disease between teeth and the gums. This biofilm results in the production of high levels of foul odors. The odors 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 malodor levels, and usually decrease following successful treatment. Other parts of the mouth may also contribute to the overall odor, but are not as common as the back of the tongue.