Xylitol is anti-fungal and can help control thrush, sore tongue or denture sore mouth. Debilitated and sick people often have sores at the corners of their mouth (angular cheilitis), a condition that xylitol can also help. A solution of 4 grams of granular xylitol in 16 oz. of warm water can be made and sipped throughout the day and night. This solution may alternatively be sprayed into the mouth or wiped onto teeth with a cloth or sponge.