Mouthwash can help rinse away food debris and bacteria after brushing, but it's not an essential part of a good oral hygiene routine. That being said, it doesn’t do any harm either, and can help fight bad breath.
Many people enjoy rinsing with mouthwash after they’ve brushed their teeth, because they feel that the mouthwash is clearing away all that loose debris left over after brushing.
While this is true, rinsing with water after brushing has the same effect.
More than anything else, mouthwash is a good addition to a proper oral hygiene routine, it is not a substitute. Mouthwash should never take the place of brushing, flossing, and visiting the dentist, but it can help freshen your breath, and it’s generally harmless.
That might surprise you, if you’ve heard about the studies over the years that connect mouthwash use to things like cancer and heart disease.
For example, one study in the journal Free Radical Biology and Medicine found that some mouthwashes could raise blood pressure by wiping out a type of mouth bacteria that helps the body generate nitric oxide. Nitric oxide is known to play a critical role in protecting the cardiovascular system, which includes keeping blood pressure down.
However, this study focuses specifically on mouthwashes that contain a strong antibacterial agent called chlorhexidine. Mouthwashes containing cholorhexidine are typically only available by prescription. It was also a very small study of only 19 participants, and requires more research to support its findings.
Some studies in the 90s suggested mouthwashes that contain alcohol might contribute to the development of oral cancers. But many experts say that these studies were flawed, and focus on excessive mouthwash use—three or more rinses a day.
Several follow-up review studies have failed to find links between alcohol rinses and cancer.
Regardless of these studies, it's important to note that mouthwashes with alcohol in them can dry out your mouth. If you have issues with dry mouth and want to use mouthwash be sure to choose an alcohol-free version.
Antibacterial or antiseptic mouth rinses present a more complicated issue. Only people who have periodontal disease or other harmful types of oral bacteria should use these types of rinses. Be sure to consult with your dentist before using any of these mouth rinses.
For those people with healthy teeth and mouths who want to use mouthwash, select a mild variety without alcohol or strong antibacterial agents.
Ultimately, mouthwash might feel refreshing to use, but it doesn’t do much other than (possibly) help reduce bad breath. If you like using mouthwash, there’s no medical reason not to rinse with it once or twice a day, but if you want to save some money, just rinse with water instead.