health

The exact cause of canker sores is not known; however, some doctors
think that the sores develop when the person’s immune system targets
the tissues of the mouth.

There are a number of possible factors that may
trigger such a reaction:

• Trauma. Canker sores sometimes develop when a person’s mouth
  is irritated by poorly fitted dentures, loose wires from orthodontic
  braces, a rough tooth, or accidentally biting the inside of the
  mouth. Brushing too hard or using a very stiff toothbrush have
  also been associated with damage to the lining of the mouth and
  canker sores.
• Nutritional deficiencies. People who are not getting enough
  vitamin B12, iron, zinc, or folic acid in their diet are more likely
  to develop canker sores.
• Infection by Helicobacter pylori, the same bacterium that causes
  stomach ulcers.
• Stress. Researchers have noted that high-achieving people and
  people with higher-than-average anxiety levels are more likely to
  develop canker sores.
• In women, hormonal changes during menstruation and pregnancy
  are often associated with an outbreak of canker sores.
• AIDS and other disorders that affect the immune system.
• Food allergies. Flavoring agents, essential oils,
  benzoic acid, cinnamon, gluten, cow’s milk, coffee,
  chocolate, potatoes, cheese, figs, nuts, citrus fruits,
  and certain spices have all been associated with canker sores
  in some people.
• Sensitivity to certain chemicals found in toothpastes
  and mouthwashes, particularly sodium lauryl sulfate (SLS),
  a chemical added to toothpaste to thicken it
  and create a lather during brushing.

When to Call the Dentist :

Canker sores, particularly minor sores, usually heal without difficulty
even though they may be painful for a week or so.
Patients should, however, see their dentist or doctor if they have any
of the following symptoms, which are not normal for
ordinary canker sores:

• Fever, particularly fever of 101°F
  (38.3°C) or higher
• Headache
• Pains in the muscles and joints
• Unusually large sores
• New sores developing before old ones
  heal
• Sores that extend outward from the
  lining of the mouth into the lips
• Pain that cannot be controlled by
  ordinary self-care treatments
• Severe difficulty in eating or drinking
  
• Nausea, vomiting, or diarrhea
  
• Sore throat or swollen glands in the neck
  
• Rash on the face or body