Halitosis may be related to a variety of causes, including bacterial infections and medications. Some bacteria in your mouth may produce gaseous compounds that cause bad breath. For some people, bad breath is caused by a dry mouth, which may be a result of medications you are taking or other medical conditions you may have.
Bad breath is often found in people with periodontal diseases, including gum abscesses and mouth sores. These diseases are usually attributed to less than admirable oral hygiene, dentures, smoking or teeth restoration, such as bridges.
Brushing, flossing and seeing your dentist regularly may reduce bad breath. Some dental hygienists recommend brushing your tongue, since it traps large amounts of bacteria. Additional protection against the buildup of bacteria in your mouth can be achieved by rinsing with a mouthwash after you finish brushing.