If the child is being breastfed... yes, they are getting everything they need. If they are bottle-fed, most powdered formulas do contain fluoride but pediatricians still recommend mixing it with bottled, low-fluoridated water (not tap water) although some will recommend fluoride-free since the formula contains it already (this is to prevent fluorosis - the condition that can cause white streaks or spots on the forming teeth.) If they are under two and therefore not using fluoridated toothpaste but drinking milk then milk has systemic fluoride and you should be fine. If the child is older but no longer breastfed, not drinking enough milk, not drinking any tap (or well water) or eating a well-balanced diet of other fluoride sources such as yams and fish then I'm sorry, but using fluoridated toothpaste is not enough. The child should have systemic fluoride to aid in mineralization of enamel. Keeping the sugar and bacteria off of the teeth in the first place is another topic entirely.