I took my kids to the dentist the other day – no cavities! However, my kids had a bunch of questions about their teeth and how cavities are formed. We have talked about how to care for their teeth and brush properly, but I thought that this egg experiment would be a great hands-on visual for answering their questions.
It is an egg experiment that I have done in kindergarten for many years. The shell of the egg is similar to our tooth enamel. We used six eggs and covered three of them in toothpaste .
We put two eggs in water. One egg with toothpaste the other without. We also put two eggs into pop. Again, one with toothpaste and one without. We then repeated with vinegar.
My kids made great observations right away that some of the eggs began to bubble and one egg even floated! We guessed what we thought would happen. We then left the eggs for about a day and a half.
Once we took the eggs out of the cups we talked about what we saw and how the eggs had changed. Our eggs in the water, did not look any different from each other or from when we first put them in.
We figured that this shows that water is okay for our teeth and does not hurt them. The toothpaste was not needed to protect them.
Our eggs in the vinegar were a different story. The enamel completely rubbed off of the egg without toothpaste. The enamel on the egg with toothpaste also largely rubbed off, but not to the same extent as the one without toothpaste.
The really interesting thing with this egg was that the egg was squishy and we could actually bounce it! The vinegar had completely changed the feel and structure of the egg. The enamel of the egg was no longer making it strong.
Just like teeth! If we eat a lot of acidic foods, like lemons, it can begin to break down our enamel and make our teeth less strong.
Finally, our eggs that were left in the pop show the clearest how toothpaste helps. The egg with toothpaste was considerably less stained than the other egg. We learned so much from this egg experiment about how important it is to protect our teeth with toothpaste and healthy foods!
40 minute activity time includes follow up time once eggs have been in the liquids for over a day.