I went to the dentist today and was mentioning to her long-time hygenist about the fluoride trays that have been used by so many in here. She asked if I would pose the question as to what kind (brand name, etc.) folks used, as the ones they use in her practice are very runny. When they tried a new one, it hardened like cement, so could you help by just mentioning what kind of fluoride your dental or ENT office suggested? Thanks so much...JaneP.