Volatile Sulfur Compounds are the cause of bad breath. This can be the result of tobacco or alcohol use as well as the consumption of ethnic foods that may be high in garlic, onions or spices. Other sources are medical or chemical in their origins. Unfortunately, some of the medications used to treat these problems themselves contribute to bad breath. Decrease in saliva flow in the mouth is associated with bad breath.
Bacteria are the major source of all bad breath.
All these previous conditions enhance the formation of dental plaque, a film of sticky material and bacteria found on tooth, gum and tongue surfaces. Poor oral hygiene, faulty dental appliances, fillings, and caps increase the risk of creating an environment favorable for bacterial and plaque growth. VSCs are found first on the tongue and later on the gums and other oral tissues.