You will notice that it requires more time to keep your teeth clean with braces. Food tends to get stuck in the brackets and between your teeth, and it can only be removed by brushing and flossing. In order to get the floss under your wires, use floss threaders. If plaque remains on the teeth for any length of time, it will leave a permanent white scar on the surface. Brushing after meals should become part of your daily schedule. Make sure to use the special fluoride gel prescribed by your orthodontist every day. It will not only prevent cavities but also help prevent decalcification around the brackets of your braces.
Below is a short video by the American Association of Orthodontists showing the best practice of brushing and flossing while wearing braces.
Brushing and flossing tips
AAO - Brushing And Flossing While Wearing Braces