Tooth mousse, it's meant to protect the enamel on your teenth.

护牙素，用来保护牙釉质的。

Enamel is the hard mineralized outer layer of the tooth.

牙釉质是牙齿坚硬的矿化外层。

The tooth has an enamel covering so it's relatively shiny.

牙齿表层有牙釉质 所以稍微亮些。

This acid can cause holes, called cavities, to form in the enamel of your teeth.

这些酸会造蛀牙，在牙釉质表面。

So building enamel is like making rocks in your mouth.

所以生产牙釉质就像在你嘴里生产岩石。

If you zoom way in, tooth enamel looks almost like the weave of a basket.

如果放大牙釉质，它与篮子的纹理常相近。

And your teeth aren't hard enamel all the way through.

并且牙齿并不是全都是牙釉质。

The organoids happily churned out the chemical components of enamel.

类器官愉快地分泌出了牙釉质的化学分。

Even with protective enamel ridges, these teeth would gradually have worn down.

即使是有保护釉质的脊，这些牙齿也会逐渐被磨损。

Many foods weaken our enamel and brushing right after can actually damage your teeth.

许多食物损伤牙釉质，吃完饭后就刷牙，实际上也损伤牙齿。

Millions of these rods packed together make up the enamel layer of your teeth.

这些千上万的结晶物排列堆积，了你的牙釉质。

Enamel is the strongest stuff in your whole body -- even stronger than bone!

牙釉质是全身最坚硬的东西，甚至比骨头还硬。

Dentin is pretty hard, but unlike enamel, it's porous.

牙本质常硬，但与牙釉质不同，它是多孔的。

But synthetic formulations can be less durable than human enamel.

但合配方可能不如人类牙釉质耐用。

For enamel, this process produces long, thin strands, each about 60 nanometers in diameter.

在生牙釉质的过程中会产生细长的纤维状物，每条纤维的直径宽约60纳米。

The process of building enamel is some awesome cellular nanotechnology, up in your face.

釉质的过程是一种奇妙的细胞纳米技术，而这就发生在你的脸上。

When all this enamel nano-fabrication is complete, your baby teeth finally bust out.

当所有这些纳米制造牙釉质过程完，你的乳牙就最终了。

Well now materials scientists have been able to figure out why—by mapping the nanostructure of tooth enamel.

现在材料科学家们通过绘制牙釉质的纳米结构已经知晓其中的原因。

The enamel contains chemical signatures of a local soil, passed by the plants the mastodons ate.

通过他们所吃的食物，牙齿上的釉质带有一些当地土壤的化学分。

But another reason, they say, is the iron-enriched glue in beaver enamel—which was even more acid-resistant than fluoride-treated enamel.

但他们称另一个原因则是海狸牙釉质中富含铁的胶质—相比氟这种牙釉质在耐酸上更胜一筹。