I have been seeing a lot of questions on bad breath. Bad breath is caused by many factors like calculus, food debris, poor oral hygiene, use of tobacco, other medical problems like decreased saliva due to radiation, or any other medication's. It may be also due to gastric problems and worm infestation. The most common treatment is a professional cleaning and maintaining good oral hygiene. People with decreased saliva can chew on bubble gum or sip citrus fruits to stimulation of salivary gland. Patients with acid reflux should consult a gastrointestinal specialist.