4 doctors weighed in:
Recurring canker sores? Why do I get them?
4 doctors weighed in

Dr. Richard Ruden
Dentistry
1 doctor agrees
In brief: Many causes
The cause of canker sores is not well understood.
More than one cause is likely, even for individual patients. Canker sores do not appear to be caused by viruses or bacteria, although an allergy to a type of bacterium commonly found in the mouth may trigger them in some people. The sores may be an allergic reaction to certain foods. In addition, your own immune system can cause them.

In brief: Many causes
The cause of canker sores is not well understood.
More than one cause is likely, even for individual patients. Canker sores do not appear to be caused by viruses or bacteria, although an allergy to a type of bacterium commonly found in the mouth may trigger them in some people. The sores may be an allergic reaction to certain foods. In addition, your own immune system can cause them.
Dr. Richard Ruden
Dr. Richard Ruden
Thank
Dr. Charles Cattano
Internal Medicine - Gastroenterology
1 doctor agrees
In brief: Depends on cause
Aphthous stomatitis involving the common canker sore can occur in up to 15% of americans, and may involve some bacteria like staph epidermidis.
However, similar-appearing aphthous ulcers can be seen with herpes, crohn's disease, and other systemic disorders, if you have multiple aphthous ulcers or frequently recurring ones please have the lesions checked out.

In brief: Depends on cause
Aphthous stomatitis involving the common canker sore can occur in up to 15% of americans, and may involve some bacteria like staph epidermidis.
However, similar-appearing aphthous ulcers can be seen with herpes, crohn's disease, and other systemic disorders, if you have multiple aphthous ulcers or frequently recurring ones please have the lesions checked out.
Dr. Charles Cattano
Dr. Charles Cattano
Thank
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