Method - How to test it

Staining the egg:
1.Place egg into pot filled with water
2.Boil water in pot until bubbly
3.Boil for 5 minutes
4.Take the egg(s) out of the pot and run under cold water
5.Boil your kettle, meanwhile you can place 2 teaspoons of coffee into a small and tall round container (preferably plastic or glass)
6.Pour one cup of hot water from the kettle into the same container
7.Wait for the coffee to cool down before you place the egg into it.
8. Soak the egg(s) in coffee for 11 hours and 45 minutes (8:00pm - 7:45am)

Testing
1.Brush the egg with Colgate's 'Maximum Cavity Protection toothpaste' for 200 up and down strokes. (up and down count as one stroke)
2. Take another coffee soaked egg and soak the toothbrush in a cup of water for 10 seconds. Brush for 200 strokes.
3. Record your results.
4. Repeat these steps three times and record your results for each test