My husband has used it for a couple of years as suggested by his dentist & now has sores'eruptions along the gum line & the tongue that were biopsied & are 'pre-malignant'. I was concerned it may have been the toothpaste (he now has stopped using it!) as it is to be used as a toothpaste but left in the mouth during the day after morning brushing & over-night after brushing ... not rinsed out after use.