Brushing at night is the most important. Saliva naturally fights
the growth of bacteria on your teeth. Your mouth dries out at
night and reduces your mouths ability to do this. Ideally you
would keep your teeth clean at all times but thats of course not
realistic. A while back I read many websites and opinions about
this very question. The main consensus seemed to be that people
brush in the morning because it makes them feel good to start
their day with a clean mouth (not because it's the best time to
do it). Here is a discussion about it: During the day, you're
flapping your jaw, drinking water, chewing gum, and moving your
tounge, all of which help to clean things off of your teeth. At
night, your mouth is much less active, which allows bacteria
more time to grow without being mechanicalyl sloughed off. Many
years ago my orthodontist told me that it was most important to
brush your teeth before going to sleep (I guess either for the
night, or for a nap). Saliva production is down, and if you
happen to slee