Fluoride in drinking water is the best way to get fluoride.  Fluoride is important for teeth because it decreases your chances of getting cavities because it makes them stronger.  Your child may not be getting enough fluoride if your water district does not fluoridate the water or if your family drinks a lot of bottled water that does not contain fluoride.  Your pediatric dentist may prescribe fluoride paste for home and regular fluoride treatments in the office.