The recommendation is to brush and floss after every meal and before going to bed. How well you brush and the amount of time spent brushing is very important. Brushing and flossing are especially important when you have braces because food can get caught in the braces and cause cavities. It is also recommended to brush with a fluoride gel in an attempt to avoid cavities, or use a fluoride rinse after brushing. Fluoride gel products are now available from your pharmacist without a prescription.