Stomatitis meaning "inflammation". Malnutrition (improper dietary intake) or malabsorption (poor absorption of nutrients into the body) can lead to nutritional deficiency states, several of which can lead to stomatitis. For example, deficiencies of iron, vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B6 (pyridoxine), vitamin B9 (folic acid) or vitamin B12 (cobalamine) may all manifest as stomatitis. Iron is necessary for the upregulation of transcriptional elements for cell replication and repair. Lack of iron can cause genetic downregulation of these elements, leading to ineffective repair and regeneration of epithelial cells, especially in the mouth and lips. Many disorders which cause malabsorption can
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