Answer to Question 1
pica
Answer to Question 2
Because it has long been recognized that dietary fluoride strengthens bones and teeth, I would recommend that parents provide adequate, but not excessive, amounts of dietary and topical fluoride for young children. The principles to remember are:
Fluoride strengthens bones and teeth by being incorporated into their basic mineral matrices. Bones and teeth that contain fluoride are stronger than those without it, being especially resistant to bacterial breakdown and cavities. Consuming fluoride also appears to stimulate maturation of osteoblasts, the cells that build new bone.
Very few foods are good sources of fluoride, although potatoes, tea, and legumes contain some fluoride, as does fish with intact bones. Thus, consuming water that has been fluoridated is likely the best source of dietary fluoride in many communities.
Topical (not dietary) application of fluoride-containing toothpaste and fluoride treatments works directly on the cavity-causing bacteria in the mouth to decrease acid production. The damaging effects of acids produced by these bacteria are largely responsible for tooth decay. Thus lower acid production means fewer cavities.
Because fluoride toxicity can occur in small children who swallow large amounts of fluoride toothpaste on a daily basis, adults should supervise children while they are brushing their teeth and store fluoridated toothpaste out of the reach of children.