Please consider eliminating all your teeth, I know it's extreme but I had the same problem for many years it went away... I have no more bad breath. ..I still have my bottom teeth, they were cleaned deeply. And I had to Remove my upper teeth, try deep cleaning first..if that doesn't work then you must extract your teeth. ..like I said my bad breath went away, , I'd rather have no teeth then bad breath. ..just saying. .. POOPLESS BREATH...