Fluoride is a form of the chemical element fluorine. It is used as medicine. Fluoride protects teeth from the bacteria in plaque. It also promotes new bone formation.
Fluoride is added to public drinking water to prevent tooth decay. Children who do not drink fluorinated public water because their homes use water from a private well often take fluoride tablets to prevent tooth decay. Fluoride is added to toothpaste and mouthwashes so it can be applied directly to the teeth to prevent tooth decay.