Overview WHY FLOSS? Because a toothbrush misses cleaning between your teeth. Regular brushing cleans only 3 out of the 5 surfaces of each tooth. The basis for good dental health is healthy gums, and flossing regularly between each tooth is an ideal way of maintaining healthy gums for all age groups. Healthy gums overlap the teeth and so prevent bacteria from contaminating the sensitive tissue underneath. If plaque is allowed to form it does so especially at the junction of the teeth and gums. This lets the gums separate from the teeth so bacteria can enter, resulting in bleeding gums (which are the first sign of gingivitis), and bad breath. If gum infection is left untreated it will worsen and may even result in infection, leading to loosening teeth, receding gums and eventual tooth loss.