hmm.
Is it possible that I can actually feel that my teeth are harder after only two days using this fluoride rinse that's supposed not only to prevent cavities, but also to restore weak spots that might already be there? (Ever since April, when I had to go to an emergency dentist in Lowell, Massachusetts so they could remove and replace a filling I'd had put in only the previous December, I've been paranoid and anxious about that tooth. Lately it's been feeling maybe a little twingier again, but it doesn't hurt or feel hollow when I tap on it, so I'm not actually actively afraid -- but I am a little nervous, because the last thing I want is bridge work. So: swishing anti-cavity stuff in addition to the brushing and flossing. Hurrah!) Or is this just a great big placebo effect?