Getting It Done: Try to make flossing a priority in your daily life. It makes no difference when you choose to floss- morning or night-just pick a time of day when you can devote an extra couple of minutes to your oral hygiene. Adults, teenagers, and children need to floss. Children should have an adult floss their teeth as soon as they have two teeth that touch as to prevent cavities. For all ages, be sure to gently move floss up and down the side of the tooth and under the gum between the tooth and gum tissue. This will help in the prevention of cavities and periodontal disease.