DEAR DOCTOR K: I brush and floss regularly. Do I need to use mouthwash too?
DEAR READER: Judging from the ads, you need mouthwash to prevent plaque (the yellowish film of bacteria that attaches to your teeth and leads to cavities) and gingivitis (inflammation of the gums). But mouthwash actually plays a fairly minor role in the prevention of plaque and gum disease. Brushing and flossing are much more important.
Cavities, gingivitis and bad breath are all caused by certain bacteria that live in every person's mouth. You can't eliminate them, but you can reduce their number and prevent the damage they can cause.
Mouthwash has a history that goes back thousands of years. People have used rinses made with everything from betel leaves to dill and myrrh dissolved in white wine. Listerine was first developed in the late 19th century as a surgical antiseptic. It was named after the British surgeon, Sir Joseph Lister, who pioneered the prevention and treatment of bacterial infections that occurred following surgery.
These days, many mouthwashes are highly artificial concoctions that contain sweeteners for taste and artificial colorings for a bright hue. Alcohol is often included as well.
It's true that mouthwash will make your breath smell better for a while. The question is whether that's achieved by killing off odor-producing bacteria or merely masking the problem. More effective than mouthwash at masking the problem are breath mints. It's easier to use them repeatedly during the day than to swish mouthwash repeatedly.
The most effective way to reduce bad breath is to brush your tongue when you're brushing your teeth. Most of the bacteria that cause bad breath reside in a small area near the back of the tongue. Brushing them away with a toothbrush is more effective than rinsing with a mouthwash.
On the other hand, some research has found that two antibacterial ingredients most commonly used in mouthwashes may reduce the levels of bacteria that produce bad breath. What's more, other mouthwash ingredients (zinc and chlorine dioxide) may neutralize other smelly compounds.
What about gum disease? There are about a dozen species of bacteria, found in plaque, that cause gum disease. They cause inflammation that can break down gum tissue and the bone that holds teeth in place.
Brushing and flossing are the best ways to remove plaque, but the antibacterial ingredients in some mouthwashes do have a modest effect. Look for mouthwashes that have the American Dental Association's (ADA's) "Seal of Acceptance" as a plaque fighter.
Finally, most mouthwashes do not prevent cavities -- nor do they claim to. Some newer mouthwashes contain fluoride, and some of them have the ADA's blessing as proven cavity fighters.
So it's fine to use mouthwash, but brushing and flossing are still the mainstays in preventing cavities and gum disease.