Fluorine is a pale-yellow, gaseous halogen element, the most electronegative and most reactive of all the elements, used in a wide variety of industrially important compounds.
Fluoride is the ionic form of fluorine. Fluoride is used orally to help protect the bones and teeth and for osteoporosis. Fluroride protects the teeth by interfering with the metabolism of bacteria in plaque. It helps preserve the tooth enamel.
Fluoride also helps the body by stimulating osteoblast activity. Thus, it helps preserve the bones.
Fluoride can be found in the diet naturally through fluorinated water, beverages, and some foods. Fluoride is also often present in dental care products.