Do you ever feel like you and a friend are speaking past each other?

Or that you're not sure how to break out of a rut?

I'm Shankar Vedantam, host of the podcast Hidden Brain.

We explore questions that keep you up at night

and provide answers that are grounded in rigorous science.

Join us each week to explore your Hidden Brain.

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Hey, do me a favor. Take a moment and just smile.

That's it. Give me a big old smile with lots of teeth.

Nice. But wait a second. I noticed something about a lot of your smiles,

especially if you're between the ages of eight and fourteen.

You're wearing races.

Now, I know what you're thinking. Some of you might be embarrassed, and others don't want to talk about it.

And a few of you are like, yeah, thanks for reminding me why my teeth hurt.

Because yes, braces can be a sore subject, literally.

And for those of you who are younger than eight, there's a good chance braces are in your future.

But why? Why do so many kids have to wear braces?

What was life like before dental braces were invented?

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