The Vitamin Deficiencies that causes angular cheilitis are the B(B2-riboflavin) Vitamin and also the Iron Deficiency also known as Anemia which is often a result of malnutrition but can also be caused by malabsorbtion.
You can help get rid of and treat angular cheilitis by several different methods such as, using lip balm regularly to prevent chapped lips, applying petroleum jelly to the corners of the mouth or even applying coconut oil to the corners of the mouth, which can help dry skin.