What Substance is Most Effective for Cleaning Teeth

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Updated on Apr 29, 2010

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To determine which tooth cleaner most effectively protects teeth from sugars and acids that dimineralize and decalcify tooth enamel.

Materials Needed

  • 12 extracted molars (approximately the same age and in good condition, available from a dentist's office)
  • water
  • 12 empty petri dishes
  • soda pop
  • lemon juice
  • toothbursh
  • baking soda
  • mouthwash
  • fluoridated toothpaste
  • nonfluoridated toothpaste
  • tartar-control toothpaste


Twelve different molars will be exposed to sugars and acids (soda pop and lemon juice) for a period of three weeks. Each of ten teeth will be cleaned daily with one of the cleaners. The two remaining teeth will serve as the control and will be brushed with water only. At the end of three weeks the condition of the molars will be carefully obser ved to determine which substance worked the best as a cleaner and provided the greatest protection.


  1. Rinse the teeth with boiling water and dr y them thoroughly.
  2. Fill six empty petri dishes three-fourths full with soda pop. Then fill the other six empty petri dishes three-fourths full with lemon juice.
  3. Place a molar into each dish, cover it, and label it according to the type of cleaning solution with which it will be brushed. For example, begin by labeling one molar in the soda pop solution SP—baking soda and one molar in the lemon juice solution LJ—baking soda, and so on.
  4. Soak each tooth in its solution for 24 hours. Then remove the teeth individually and brush them with the substance that is labeled on their particular dishes. Mer cleaning, return the teeth to their petri dishes, cover, and repeat the same procedure daily for three weeks. At the end of the period observe the condition of each tooth. Look for signs of deterioration and discoloring.


  1. Did any of the teeth show signs of deterioration and discoloring? If so, what changes did you observe? Were these changes consistent among all the teeth, or did they vary?
  2. Which substance, soda pop or lemon juice, had the greatest impact, if any, on the molars?
  3. Which substance, if any, kept the teeth clean and protected the longest? Does this result agree or disagree with what your dentist recommends as a tooth cleaner?