Aphthous stomatitis mouth, with or without oral ulceration. It may describe many different conditions apart from aphthous stomatitis such as angular stomatitis. The current most widely used medical term is "recurrent aphthous stomatitis" or simply "aphthous stomatitis". Historically, many different terms have been used to refer to recurrent aphthous stomatitis or its sub-types, and some are still in use. Mikulicz' aphthae is a synonym of minor RAS, named after Jan Mikulicz-Radecki. Synonyms for major RAS include Sutton's ulcers (named after Richard Lightburn Sutton), Sutton's disease, Sutton's syndrome and pariadenitis mucosa necrotica recurrens. Synonyms for aphthous stomatitis as a whole include (recurrent) oral
The Canon of Medicine anatomy, and physiology. The book explains the causes of health and disease. Avicenna believed that the human body cannot be restored to health unless the causes of both health and disease are determined. He defined medicine ("tibb") as follows: Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause: Avicenna's thesis on the elements of the cosmos is described by Gruner as "the foundation of the whole "Canon"". Avicenna insists here