A Fun Eggsperiment!

Here's something fun to try at home or maybe for a science project! It takes about five days. In this experiment the eggs represent the teeth and the vinegar represents the acids that are made by plaque that can cause cavities. (Note: Don't eat the ingredients after the experiment!)



  1. Allow eggs to warm to room temperature. With clean hands, wash the egg with water and dry with the paper towel.
  2. Put about one inch of toothpaste into the bottom of measuring cup and pat down with a spoon and remove any air bubbles.
  3. Mark one side of the egg with a marker and cover this mark with clear nail polish to protect it from the vinegar.
  4. After the nail polish has dried, place the egg into the measuring cup, marked side down so the toothpaste covers half the egg. Make sure the egg does not touch the bottom of the cup.
  5. Cover the cup tightly with plastic wrap and leave it in a safe place at room temperature for at least four full days (96 hours).
  6. After the treatment, with clean hands, rinse the toothpaste off the egg with warm water and let the egg dry overnight.
  7. Pour enough vinegar into a clean measuring cup to cover the egg, and then carefully place the egg into the vinegar with a spoon. Rest the spoon on top of the egg to keep it submerged under the vinegar and cover the cup with the plastic wrap. You'll notice bubbles starting to form on the side of the egg that was NOT treated with toothpaste.
  8. Leave the egg in the vinegar until the untreated side (unmarked side) of the egg softens. This will take about 7 to 13 hours.
  9. After 7 hours or so in the vinegar, remove the egg and check if the side not treated with toothpaste has softened by tapping it very lightly you a finger or pen.
  10. If the untreated side is still hard, put the egg back into the vinegar. Then check the egg every few hours until it has softened.
  11. When the untreated side is soft, remove the egg and gently wash with warm water. The egg is very fragile so be careful.

Now you should notice that the acid has made the side that was NOT treated with toothpaste very soft—kind of like the acid in plaque would cause a cavity on a tooth. Yet the side of the egg that was treated with toothpaste was kept strong and hard—kind of like teeth that have been brushed and kept clean to protect it from acid attack.