The key to keeping a bright and healthy smile throughout adulthood is to practice proper oral hygiene. Adults can get cavities, and gum disease that can lead to serious problems. To keep your smile sparkling it is important to continue to: Brush twice a day! Floss daily to remove plaque from between your teeth and under your gum line, before it can harden and turns into tartar. Once this has formed, it can only be removed by a dental hygienist during a professional cleaning.