Mouth rinses and toothpastes. If your bad breath is due to a buildup of bacteria (plaque) on your teeth, your dentist may recommend a mouth rinse that kills the bacteria. Your dentist may also recommend a toothpaste that contains an antibacterial agent to kill the bacteria that cause plaque buildup.
If you have gum disease, you may be referred to a gum specialist (periodontist). Gum disease can cause gums to pull away from your teeth, leaving deep pockets that fill with odor-causing bacteria. Sometimes only professional cleaning removes these bacteria. Your dentist might also recommend replacing faulty tooth restorations, a breeding ground for bacteria.
If bad breath is due to a health problem such as a sinus infection, diabetes, acid reflux, etc., then the underlying medical issue needs to be treated.
If bad breath is a side effect of taking a medication, discuss with a doctor whether there are other options for medication that can be taken. Never stop taking a medication without first consulting your doctor.
Toothbrushes can’t reach the back of the tongue where the bacterial causes of bad breath reside; so although brushing plays an important role in oral hygiene, it is not a bad breath cure. Since mouthwashes only temporarily mask and do not eliminate the odor-causing bacteria, they too are not an effective chronic bad breath treatment.
If you still have bad breath after making changes to your dental hygiene, you may want to try Source: natural bad breath treatment remedies.