Yes, these terms are just other names for the appearance of canker sores. A canker sore is often referred to as an aphthous ulcer or oral ulcer . Recurrent Aphthous Stomatitis is the medical term given to an outbreak of canker sores. Here, at the Relief Center we use all the terms interchangeably. This is an active area of research.
Current theories point to canker sores being the result of a localized autoimmune disorder.
While the immune dysfunction is thought to be the underlying mechanism of canker sore formation, it is believed that certain factors may initiate the chain of events leading to canker sore formation. These factors include sensitivity to certain foods, certain ingredients in toothpaste, stress, and trauma to the lining of the mouth. Both are painful and both are often caused by stress. Although they frequently appear on the lips and edges of the mouth, cold sores can occur in the mouth as well where they may be mistaken for canker sores. The main differences are that inside the mouth cold sores tend to occur more on the bound or non-movable parts of the mouth such as the roof of the mouth.