The Importance of Brushing Your Teeth - Part I

We've previously looked at the importance of brushing teeth to remove stains that certain foods may leave on the teeth.  This week and next we'll examine the importance of brushing teeth as a preventative measure.

The fluorine in toothpaste binds with calcium in your teeth to form calcium fluoride, which strengthens your teeth.

For this experiment, you'll want to make sure you use a fluoride toothpaste.  You'll see it listed in the active ingredients as sodium fluoride.

To represent our teeth, you'll be using an egg, as the shell is made of calcium, as are our teeth.

Coat one egg with toothpaste - all over.  Allow the egg to sit overnight with the toothpaste on it. 

The next day, wash the toothpaste off the egg.  Then place that egg in a cup/beaker of vinegar.  Place a second, untreated egg in a second cup/beaker of vinegar. 

The vinegar is an acid, as are many of the foods we consume, including, but not limited to fruit, tomatoes, and soda.

Observe the eggs over the course of the next 24 hours. 

You will notice that the cup with the untreated egg develops a foamy white substance on the top of the vinegar in a fairly short amount of time.  That foam is made of dissolved calcium - the shell is dissolving.  The treated egg does not produce nearly so much.

After 24 hours you'll notice that the untreated egg has completely lost its shell - you're left with a squishy egg.  The treated egg has a small amount of shell left.  It's on the squishy side - the fluoride doesn't completely protect it.  That's one of the reasons why you need to continue to brush your teeth - to constantly provide more fluoride and to help wash away the acid currently in the mouth.  It's also important to note that even with regular brushing, eating a diet high in acidic foods will, over time, wear on your teeth.  And lots of acidic foods without brushing your teeth is a recipe for ruining your teeth.