Tiny Tech #28: Nanodentistry

Today from the world of Tiny Tech:

Teeth make eating possible, sharks scary, and smiles pretty. But when you have a cavity, you need to see a dentist. For over 200 years, dentists have been filling cavities with amalgams, which are mixtures of silver, mercury, and other metals. Since the 1970s, however, dentists have increasingly been using a new material called a composite, which is made by adding powdered quartz to a plastic resin.

But the first composite fillings had some problems: they weren’t as hard or smooth as amalgams, and they tended to discolor with time. Over the last 20 years, the composites have been steadily improved by shrinking the quartz particles. Today, some cavity filling composites use quartz particles as small as two nanometers in size, which is about ten thousand times smaller than the diameter of a human hair. In fact, the particles are so small that they cannot be made by grinding quartz, but instead must be made by a chemical reaction. And scientists are investigating ways to further improve the ingredients in the nanocomposites so that they even more closely resemble the enamel in your teeth.

So someday Little Red Riding Hood may say, my what big nanocomposites you have, grandma!

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