Has anyone ever heard of an ototoxic reaction to toothpastes with the sensitivity agent, potassium nitrate, in them after prolonged use? I was using this product x6 months, 2-3x per day at the advice of my dentist...developed a full feeling in the inner ear, some hearing loss, and tinnitus. ENT could find no infection, no trauma, no inflammation, nothing- I stopped using the toothpaste- within 2 days there was improvement noted in the plugged/fullness feeling in the ear. Within 2 weeks, the sensation of fullness was completely gone- the tinnitus diminished, but remains, although it is slight. Unfortunately, the loss of certain higher frequencies remains in regard to the hearing. For me, there was a direct correlation with the discontinuation of the product. Anyone else have any such experiences, or know of any data regarding same?