Source. Cavities and gum disease can cause bad odor; need to check with your dentist.
Multiple Answers. First find the cause and deal with that directly. Typically, bad breath stems from bacteria between teeth, on the tongue and around the gums. Fortunately, this problem is often easy to fix: good oral hygiene (brushing 2x day, flossing & brushing your tongue), regular visits to your dentist (to prevent gum disease), and ruling out any underlying conditions or other factors.
BIOS protocol. We have been treating patients with halitosis for over 27 years. We have developed bios protocol, that enables us to eliminate 99% of bacteria that cause bad breath. Long story short: halitosis is caused by bacteria. There are over 700 different types of bacteria in your mouth. About 30 of them are deadly, cause gum disease, bad breath , etc. 1 thing those bacteria have in common-they hate oxygen.
Mouth Care. Majority causes of halitosis is caused from poor oral hygiene. So brush, floss and see a dentist.