Your dentist likely will smell the breath from your mouth and the breath from your nose and rate the odor on a scale. Because the back of the tongue most often causes the smell, your dentist also may scrape it and rate its odor.

Some devices also can detect certain chemicals that cause bad breath. But these tools aren't always available.


To reduce bad breath, help avoid cavities and lower your risk of gum disease, regularly keep your mouth and teeth clean. Further treatment for bad breath can vary. If your dentist thinks another health condition is causing your bad breath, you likely will need to see your primary healthcare professional or a specialist.

Your dentist will work with you to help you better control bad breath caused by mouth issues. Dental measures may include:

  • Mouth rinses and toothpastes. If your bad breath is due to a buildup of bacteria called plaque on your teeth, your dentist may recommend a mouth rinse that kills the bacteria. Your dentist also may recommend a toothpaste that contains an antibacterial agent to kill the bacteria that cause plaque buildup.
  • Treatment of dental disease. If you have gum disease, your dentist may suggest that you see a gum specialist, known as a 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 also might recommend replacing faulty fillings, a breeding ground for bacteria.

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Lifestyle and home remedies

To reduce or prevent bad breath:

  • Brush your teeth after you eat. Keep a toothbrush at work to use after eating. Brush using a fluoride-containing toothpaste at least twice a day, especially after meals. Toothpaste with antibacterial properties has been shown to reduce bad breath.
  • Floss at least once a day. Proper flossing removes food particles and plaque from between your teeth, helping to control bad breath.
  • Brush your tongue. Your tongue collects bacteria, so carefully brushing it may reduce odors. A tongue scraper may help people who have a coated tongue from a major overgrowth of bacteria, such as from smoking or dry mouth. Or use a toothbrush that has a built-in tongue cleaner.
  • Clean bridges, dentures, retainers and mouth guards. If you wear a bridge or a denture, clean it thoroughly at least once a day or as directed by your dentist. If you have a dental retainer or mouth guard, clean it each time before you put it in your mouth. Your dentist can recommend the best cleaning product.
  • Keep your mouth moist. Stay away from tobacco and drink plenty of water. Don't take in too much caffeine, spicy food or alcohol. All can dry out your mouth. Chew gum or suck on candy, preferably sugarless, to make more saliva. For constant dry mouth, your healthcare professional may prescribe an artificial saliva preparation or a medicine that you take by mouth that raises the flow of saliva.
  • Change your diet. Stay away from foods such as onions and garlic that can cause bad breath. Eating a lot of sugary foods also is linked with bad breath.
  • Replace your toothbrush. Change your toothbrush when it becomes frayed, about every 3 to 4 months or sooner as needed. Also, choose a soft-bristled toothbrush.
  • Schedule regular dental checkups. See your dentist regularly — generally twice a year. During these checkups, your dentist can look at your teeth or dentures and clean them.

Preparing for your appointment

If you're going to see your dentist about bad breath, these tips can help:

  • Dentists generally prefer morning appointments to test for bad breath. This lowers the chances that foods you eat during the day will affect the exam.
  • Don't wear perfume, scented lotions, or scented lipstick or lip gloss to your appointment. These products could mask any odors.
  • If you've taken antibiotics within the last month, check with your dentist to see if you need to reschedule your appointment.

What to expect from your dentist

Your dentist likely will start by asking about your medical history, with questions such as:

  • When did you first begin to have bad breath?
  • Does your bad breath occur sometimes or all the time?
  • How often do you brush your teeth or clean your dentures?
  • How often do you floss?
  • What kinds of foods do you eat most often?
  • What medicines and supplements do you take?
  • What health conditions do you have?
  • Do you mainly breathe through your mouth?
  • Do you snore?
  • Do you have allergies or sinus problems?
  • What do you think might be causing your bad breath?
  • Have other people noticed and commented on your bad breath?

Be ready to answer these questions so that you can make the most of your appointment time.

Dec. 21, 2023
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