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Dental Health and Canker Sores

Canker sores are small, shallow ulcers that appear in the mouth and often make eating and talking uncomfortable. There are two types of canker sores:

  1. Simple canker sores. These may appear three or four times a year and last up to a week. They typically occur in people between 10 and 20 years of age.
  2. Complex canker sores. These are less common and occur more often in people who have previously had them.

What Causes Canker Sores?

The exact cause of most canker sores is unknown. Stress or tissue injury is thought to be the cause of simple canker sores. Certain foods -- including citrus or acidic fruits and vegetables (such as lemons, oranges, pineapples, apples, figs, tomatoes, and strawberries) -- can trigger a canker sore or make the problem worse. Sometimes a sharp tooth surface or dental appliance, such as braces or ill-fitting dentures, might also trigger canker sores.

Some cases of complex canker sores are caused by an underlying health condition, such as an impaired immune system; nutritional problems, such as vitamin B-12, zinc, folic acid, or iron deficiency; or gastrointestinal tract disease, such as celiac disease or Crohn's disease.

Are Cold Sores and Canker Sores the Same Thing?

No. Although cold sores and canker sores are often confused with each other, they are not the same. Cold sores, also called fever blisters or herpes simplex type 1, are groups of painful, fluid-filled blisters. Unlike canker sores, cold sores are caused by a virus and are extremely contagious. Also, cold sores typically appear outside the mouth -- usually under the nose, around the lips, or under the chin -- while canker sores occur inside the mouth.

What Are the Symptoms of Canker Sores?

You may have a canker sore if you have:

  • A painful sore or sores inside your mouth -- on the tongue, on the soft palate (the back portion of the roof of your mouth), or inside your cheeks
  • A tingling or burning sensation before the sores appear
  • Sores in your mouth that are round, white or gray, with a red edge or border

In severe canker sore attacks, you may also experience:

  • Fever
  • Physical sluggishness
  • Swollen lymph nodes

How Are Canker Sores Treated?

Pain from a canker sore generally lessens in a few days, and the sores usually heal without treatment in about a week or two.

If sores are large, painful, or persistent, your dentist may prescribe an antimicrobial mouth rinse, a corticosteroid ointment, or a prescription or over-the-counter solution to reduce the pain and irritation.

Can Canker Sores Be Prevented?

Although there is no cure for canker sores, and they often recur, you may be able to reduce their frequency by:

  1. Avoiding foods that irritate your mouth, including citrus fruits, acidic vegetables, and spicy foods
  2. Avoiding irritation from gum chewing
  3. Brushing with a soft-bristled brush after meals and flossing daily, which will keep your mouth free of foods that might trigger a sore

You should call your dentist about canker sores if you have:

  • Unusually large sores
  • Sores that are spreading
  • Sores that last 3 weeks or longer
  • Intolerable pain despite avoiding trigger foods and taking over-the-counter pain medication
  • Difficulty drinking enough fluids
  • A high fever with the appearance of the canker sores

WebMD Medical Reference

Reviewed by Alfred D. Wyatt Jr., DMD on June 23, 2014
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Only 18.5% of Americans never floss. You are missing out on a simple way to make a big difference in the health of your mouth. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Floss removes food trapped between the teeth and removes the film of bacteria that forms there before it turns to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Try flossing just one tooth to get started.

You are one of 31% of Americans who don't floss daily. You are missing out on a simple way to make a big difference in the health of your mouth. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Aim for 3 more days!

You are one of 31% of Americans who don't floss daily, but you're well on your way to making a positive impact on your teeth and gums. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Aim for all 7 days!

Only 50.5% of Americans floss daily, and good for you that you are one of them! Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Congratulations on your good oral health habit!

SOURCES:

American Dental Association, Healthy People 2010

This tool is intended only for adults 18 and older.

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