Fluoride

It has been observed that children who lived in places where fluoride occurred naturally in the water, had fewer dental cavities. Fluoride which is absorbed by your body is used by the cells that build your teeth to make the enamel stronger. Topical fluoride (fluoride that is applied to the outside of the enamel) makes the crystals that form enamel more durable and much more resistant to acid. They are less likely to breakdown and cause the tooth surface to become porous. Always use a toothpaste with fluoride