How Does Fluoride Strengthen Tooth Enamel?

Materials Needed

• 2 hard-boiled eggs
• Large pickle jar
• Vinegar
• Plastic food storage bag
• Fluoride gel

Process
1) Take one egg and put it in a plastic bag containing the fluoride gel. Make sure the fluoride completely covers the entire egg shell. Leave the egg in the fluoride for 24 hours. 2) Take both eggs and put them in separate jars containing vinegar. Observe the immediate difference in bubbling or reactivity of the two different eggs. Leave them in the jars overnight. 3) Take both eggs out of the jar and examine them.

Conclusion
The shell soaked in the fluoride will be hard. The egg shell not soaked in the fluoride will be soft, thus illustrating the acid resistant qualities of a fluoride-rich surface (teeth that are protected with fluoride are strong).

Note: With any science experiment, an adult should be present for supervision and safety.