Pre/Post Instructions - Do not brush 4 hours prior to appointment. You do not want any scratches or abrasions on your gums. You will be given take home instructions that include the following: Drinking water only for next 2 hours will decrease possible sensitivey. Avoid any other food or beverages for the next 2 hours (only water) Do not smoke or chew tobacco for at least 2 hours. Avoid any dark colored food or beverages NO - coffee, tea, soda, kool-aid, red wine etc. for 24 hours.