George Preti, Ph.D., Monell Chemical Senses Center, Philadelphia

Chronic halitosis originates on the far back, upper surface of the tongue (“posterior dorsal tongue surface”). In this area, some people develop a bacterial plaque that is similar to the plaque on teeth and gums. However, the tongue plaque is caused by a different group of bacteria. The malodors produced by these bacteria are very similar to those produced by fecal matter, which is why descriptions of bad breath odor can include “feces,” rotten eggs, “sewer gases,” etc.

Chronic oral malodor may leave a “malodorous cloud” in your immediate presence. This is because every time you exhale, air from your lungs passes by the far-back of the tongue and carries out some of the offensive odor. Consequently, you or others may falsely interpret this malodor as a "body odor." Some individuals with chronic halitosis produce enough odor to eventually produce an environmental malodor in an office or small space.

The tongue plaque can be thick and pervasive and must be physically removed to ameliorate the situation. We suggest the use of oral cleansing products which contain the same bacterial-killing ingredient that is used in swimming pool water; dissolved chlorine dioxide gas. Do not get products with “stabilized” chlorine dioxide; the chemistry is not right.

Carefully follow the instructions for use, including the advice to use a “breath buddy,” someone you know and trust to give you an honest opinion regarding if and how much odor is present. This is an important point, since in our clinical experience there have been many instances where we have found that regardless of an individual’s self-impression of how malodorous they are, we detect little or no odor in their presence. This may happen for numerous reasons, but it is vital for those who have had negative social encounters caused by odor production to rely on a friend or loved-one’s impression and not on the reaction of strangers.

Finally, a trial of one to two months with one of the suggested products certainly should be tried (if you haven't already) to see if it works for you. However, the tongue plaque may return if tongue cleaning is discontinued. Therefore, it is essential to make gentle tongue brushing and scraping part of routine oral hygiene. This may be done with regular toothpaste but always seek feedback from a trusted source.