It is essential for human body in a very small critical concentration range
and many harmful effects occur
in case of its excess or deficiency.
Fluorine is helpful for dental health in low dosage and added to many dental products like toothpastes, mouth rinses, gels and varnish as active ingredient.
However, chronic exposure to fluoride in large amounts interferes with bone formation and can cause skeletal fluorosis, hence the amount of fluoride intake is very important [1].