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Quiz: Why the fluoride?
by Staff
You already know how important it is to brush and floss every day -- or at least we hope you do! Chances are, the water you use to brush your teeth is fluoridated by your municipal water company. Do you know why? Find out how much you know about fluoride by taking this quiz.

Researchers noticed that towns with a higher level of natural fluoride in the water supply had a lower incidence of what?

  • gum disease
  • cavities
  • periodontitis

True or false: Fluoride in water is only effective for children, whose teeth are still developing.

  • True
  • False

What is the cost of water fluoridation per person in the United States?

  • 31 cents
  • 55 cents
  • 18 cents

When researchers in Boston began giving large doses of fluoride to rats, the female rats' offspring had what problem?

  • blindness
  • cancer
  • cognitive deficits

Fluoride protects teeth by strengthening what?

  • roots
  • gums
  • enamel

Community-wide water fluoridation began in what year?

  • 1956
  • 1973
  • 1945

Fluoridated water helps reduce tooth decay over a person's lifetime by how much?

  • 15 percent
  • 25 percent
  • 30 percent

True or false: Overexposure to fluoride in adults can lead to bone fractures or bone pain.

  • True
  • False

Every dollar invested in adding fluoride to water saves how much money in community dental costs?

  • $38
  • $125
  • $57

The U.S. Public Health Service currently recommends which range of fluoride in water?

  • 0.1 to 0.7 milligrams per liter
  • 0.10 to 0.16 milligrams per liter
  • 0.7 to 0.12 milligrams per liter

Some chemists point out that the toxicity of fluoride in water at one part per million is equal to that of what?

  • cyanide
  • arsenic
  • BPA

How much toothpaste is the safest amount to use?

  • pea-sized
  • nickel-sized
  • pinkie-sized

Tooth decay is caused by what?

  • saliva
  • bacteria
  • oxygen

True or false: Fluoride occurs naturally in water.

  • True
  • False

The process by which fluoride can prevent or reverse tooth decay is known as what?

  • carieing
  • enameling
  • remineralization

True or false: Fluoridated water causes cancer.

  • True
  • False

The United States fluoridates more than 60 percent of its water supply, whereas Canada fluoridates about how much of its water supply?

  • 40 percent
  • 70 percent
  • 80 percent

Little white specks on the teeth are part of a condition called what?

  • gingivitis
  • dental fluorosis
  • periodontitis

What is the best way to prevent cavities?

  • rinsing with fluoride
  • using an electric toothbrush
  • brushing and flossing

True or false: The rate of water fluoridation may decrease over the years.

  • True
  • False

Adding fluoride to water so that the level reaches one part fluoride per one million parts water is called what?

  • fluoridation
  • mineralization
  • enamelization