We had planned on doing a unit study for Dental Health Month in February but we got sidetracked by all of the crazy-fun frozen white stuff that was sitting outside our door, all month long.
We finally buckled down and did a few activities to learn about caring for our teeth.
We watched a couple of short videos, describing the proper way to care for your teeth, as well as teaching us the parts of teeth.
We decided to do an experiment, using hard boiled eggs.
We added one egg to a glass of Pepsi and one to vinegar. We let them sit overnight.
We talked about how the eggshell is compared to our enamel and the yolk is compared to our tooth’s pulp.
The parts of a tooth act as a house, trying to protect the pulp.
The next morning, we observed what had happened and how these eggs reacted, as our teeth do.
The egg that was left in Pepsi was completely stained. We discussed how this is what happens when you drink dark sodas or teas. Our teeth turn a different shade, due to the many unhealthy ingredients in sodas.
Our next egg, which had been left in vinegar overnight was even more interesting.
The vinegar had literally ate away the eggshell, just as sugar would eat away at your teeth’s enamel. Did you know that enamel is the hardest part of our body, yet it doesn’t ever regrow? That means if you break or chip the enamel on your tooth, you are out of luck, unless you just so happen to be a beaver. 🙂
The texture of the eggshell was very strange. It was still technically there, it was just very soft and almost flaky, for a lack of better words.
Here is a short explanation of what is happening, borrowed from Exploritorium.edu :
When you submerge an egg in vinegar, the shell dissolves. Vinegar contains acetic acid, which breaks apart the solid calcium carbonate crystals that make up the eggshell into their calcium and carbonate parts. The calcium ions float free (calcium ions are atoms that are missing electrons), while the carbonate goes to make carbon dioxide—the bubbles that you see.
This was a fun experiment for kids of all ages.