What Causes Canker Sore and How It Can Be Treated?

Canker sores are caused by:

Injuries to the mouth, as seen frequently by contact sports players. Accidentally biting the inside of the cheek or lip may also result in a canker sore
Temperature hot food or drink may cause a canker sore in the area of the mouth that was essentially burnt by the offending substance
Spicy and/or acidic foods often produce a canker sore as a response to the irritation these spices and acids create in the mouth
The use of chewing (smokeless) tobacco will often cause a canker sore to develop in the area of the mouth where the tobacco is held, due to the irritating chemicals found in the addictive product
Poor-fitting, complete or partial dentures may cause canker sores in the area of the mouth where the denture may rubbing on the tissue. The development of a canker sore is often one of the first signs that indicate the need for a denture reline or adjustment by your dentist or denturist
Orthodontic brackets, bands, and various other orthodontic attachments will often cause canker sores to develop in area of the mouth where there is constant friction on the oral tissues. This is common when orthodontic treatment first begins and may occur after each subsequent adjustments, throughout each stage of treatment
Allergies to metals such as nickel may become evident in the mouth of a person wearing orthodontic devices necessary to move the teeth. Canker sores may begin to appear adjacent to the metal attachments. This is often referred to as contact dermatitis.
Broken teeth are often sharp and may rub on the oral tissues to produce painful canker sores. Broken restorations may also cause a similar effect on the oral tissues
Emotional stress has been identified as a possible trigger that may cause the development of canker sores
Bacteria responsible for peptic ulcers known as Helicobacter pylori, has been linked to canker sore occurrence
Vitamin deficiencies, specifically vitamin B12, foliate (folic acid), and iron, may trigger canker sore development
Hormonal changes, notably during menstruation, pregnancy, and menopause, have been linked to canker sores
Canker sores often run in families. Genetics my be a factor for many canker sore sufferers
Allergic reactions and sensitivities to certain foods may cause a canker sore to develop. Allergic reaction to certain types of bacteria found in the mouth may also result in this type of mouth ulcer
Celiac disease sufferers may experience canker sores. Gluten may be associated with the development of canker sores in those with celiac disease
Information associated with inflammatory bowel disease (IBD) often will list canker sores as a complication associated with Crohn’s disease and ulcerative colitis
Mouth sores are a common occurrence observed in immuno-suppressed patients, such as those with HIV/AIDS
Behcet’s Disease, a rare autoimmune disease that damages the body’s blood vessels notes mouth sores, more specifically canker sores, as a one of the four most common symptoms of the disease
Sodium lauryl sulfate is a common ingredient in toothpaste and had been associated with the development of canker sores
Treatment is generally not necessary for most canker sores as they tend to heal quickly on their own. If canker sores persist for longer than 2 weeks, see the dentist.

See your dentist immediately if canker sores:

Become unusually larger than normal
Are extremely painful, interfering with eating, drinking, and talking
Begin to appear more frequently than normal
Do not heal after 14 days
Are accompanied by a high fever
Appear to become infected