A canker sore (or Apthous Ulcer) is a painful form of mouth ulcer. Canker sores are white or yellow and surrounded by a bright red area. They are not cancerous. A canker sore is not the same as a fever blister (cold sore).
What Causes Canker Sores?
Canker sores may occur as a result of injury from biting your tongue or cheek, or injuring your gums with a toothbrush, other utensil or hard food, from dental work such as braces, or they can also be triggered by:
- Emotional stress
- Lack of certain vitamins and minerals in the diet (especially zinc, iron, folic acid, or vitamin B-12)
- Menstrual periods or hormonal changes
- Eating too many acidic or spicy foods
- Food allergies
Sometimes, canker sores will be seen in small kids, but most often, they do not show up until between ages 10 to 20. Anyone can develop a canker sore. Women are more likely to get them than men. Canker sores may run in families.
- If you have a canker sore, be careful about what you eat. Spicy foods and acidic foods such as lemons or tomatoes can be extremely painful on these open wounds. Foods that are sharp or hard (such as nuts or potato chips), can poke or rub the sore. It’s important to keep your mouth clean, but brush gently and avoid brushing the sore itself with a toothbrush as that may cause more irritation.
- Mild, over-the-counter mouth washes or salt water may help. There are over-the-counter medicines that soothe the painful area. These medicines are applied directly to the sore area of the mouth. Ask us or your pharmacist about these medications.
- In some cases, switching toothpastes can prevent aphthous ulcers from occurring. For some people, using toothpaste that is free of sodium dodecyl sulfate (sometimes called sodium lauryl sulfate, or SDS or SLS), has been found to help reduce the amount, size, and recurrence of ulcers.
When should I call my dentist or doctor about canker sores?
If you get more than 3 canker sores a year for unexplained reasons, check with your medical doctor to see if you have a Zinc or other vitamin deficiency, a problem with your immune deficiency, or perhaps a food allergy.
If your canker sores are large, last longer than 2 weeks, or are so sore that you can’t eat or drink, you should make an appointment to see your dentist. He or she will make sure that the sore is just an apthous ulcer, and may prescribe a topical medicine (applied directly to the sore) or a special mouthwash to help.