Does mouthwash kill the mouth’s healthy bacteria?

Man pouring mouthwash from a bottle into a cap in the bathroom

Regularly swishing with mouthwash, whether to tame the scent of onions on your breath or to prevent cavities, is safe — even if it temporarily changes the balance of bacteria in your mouth. Similar to your gut, your mouth contains thousands of different types of bacteria, many of them potentially harmful. Like brushing and flossing our teeth, using a mouthwash can help bring down the level of destructive bacteria in your mouth.

The benefit of killing “bad” bacteria — for example, bacteria that promote gum disease or tooth decay — far outweighs any potential risk of offsetting the level of “good” bacteria in your mouth. And, over time, the balance of bacteria will return.

Is a probiotic mouthwash better than a standard over-the-counter mouthwash?

At this point, there’s not enough evidence that probiotic mouthwashes improve your oral health. Instead, a good daily routine to adopt is brushing your teeth twice a day for two minutes at a time, brushing your tongue (which contains a lot bacteria), flossing and drinking a lot of water.

What do mouthwashes do for us?

There are a lot of good uses for the various mouthwashes out there, most of which you can buy over the counter. Some over-the-counter mouthwashes treat gum disease, and others can relieve dry mouth, whiten teeth or reduce cavities.

A prescription mouthwash containing chlorhexidine can treat gingivitis, a gum disease that causes gums to swell and bleed. And for mouth cancer patients, some prescription mouthwashes can help in the management of mouth sores that may occur with chemotherapy or radiation.

Is it safe to use mouthwash that contains alcohol?

Alcohol was put in mouthwash to help the other ingredients dissolve, and alcohol can kill bacteria in the mouth. Depending on the brand of mouthwash you use, it can contain no alcohol or over 25% alcohol. I wouldn’t recommend alcohol mouthwash for a young child because each time you use it, you swallow a little. Also, people with sores in their mouth might find that mouthwashes with alcohol sting, so they’ll want to avoid them for that reason.

If you have chronic bad breath (halitosis), does mouthwash resolve the problem?

Mouthwash is only a temporary fix. It doesn’t get to the cause of the bad breath, which could be eating certain foods, not brushing regularly or having certain health conditions, such as diabetes or chronic acid reflux. A dentist can help determine the cause of bad breath that never seems to go away, and help you treat the cause rather than just repeatedly treating the symptom.

Healthy teeth start here

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