But for many, it's worth it. Since leaving them in can cause serious problems like gum infection, tooth decay, and even tumors.

但對很多人來說，這很值得，因為留著智齒會引發嚴重的問題，比如牙齦感染、蛀牙、甚至腫瘤。

But wisdom teeth weren't always the unwelcome threat we see today.

但是智齒並非像現在是個不受歡迎的威脅 。

Wisdom teeth have been around for millennia.

智齒已經存在了幾千年。

Our ancient ancestors used them the same way we use our other eight molars:

我們的古代祖先使用智齒的方式與我們使用其他八顆臼齒的方式相同：

to grind up food, which was especially handy before the advent of cooking around seven thousand years ago,

用來磨碎食物。大約七千年前，在發明烹煮食物前特別有用，

back when our diet consisted of raw meat and plants that were fibrous and tough to chew.

以前我們的飲食是由生肉和植物組成，多含纖維質，難以咀嚼。

But once we got our hands on softer cooked foods, our powerful jaws no longer needed to work as hard and shrank as a result.

但當我們掌握了較軟的熟食，我們强大的顎不再需要努力地工作，也因此萎縮。

But here's the problem:

但問題是：

The genes that determine the size of our jaws are completely separate from the genes that determine how many teeth we grow.

决定顎骨大小的基因完全不同於生長多少顆牙齒的基因。

So as our jaws shrank, we still kept all 32 teeth.

所以即使我們的顎骨萎縮了，我們仍然保有 32 顆牙齒。

And it eventually got to the point where there wasn't enough space to fit all of the teeth.

最終到沒有足夠空間容納所有牙齒的地步。

But why did wisdom teeth specifically get the boot?

但為什麼特別是智齒會被拋棄呢？

Well, they're the last to show up to the party.

因為他們最晚參加派對。

Wisdom teeth don't usually grow in until you're between 16 and 18 years old.

智齒通常直到你 16 到 18 歲才會生長 。

And by that time, chances are your other 28 teeth have taken up all the available space in your mouth.

到那時，你的另外 28 顆牙齒已經佔據了你口裡所有可用的空間。

In that case, instead of growing in like a normal tooth, wisdom teeth get trapped or impacted in your jaw,

在這種情況下，不會像正常的牙齒一樣生長，智齒會被困住或擠壓到你的下顎 ，

which often makes them grow in at odd angles and press against your back molars causing pain and swelling.

這往往使智齒以奇怪的角度生長，推擠你的後臼齒，導致疼痛和腫脹。

It also forms a narrow crevice between the teeth creating the perfect food trap.

智齒也在牙齒之間形成一個狹窄的縫隙，形成絕佳的食物殘渣陷阱。

This makes the tooth difficult to clean which attracts more bacteria and can cause infection and tooth decay, eventually leading to gum disease if left untreated.

這讓牙齒很難清潔，因此吸引更多細菌，也會引起感染和蛀牙，如果不治療，最終會導致牙齦疾病。

But it gets worse.

但情況會更糟。

Tooth decay can eventually destroy your wisdom tooth.

蛀牙最終會毀了你的智齒。

So, to save you and your teeth from such a horrible fate, dentists will often remove wisdom teeth before they go rogue.

所以，為了拯救你和你的牙齒擺脫這樣可怕的命運，牙醫經常在智齒製造麻煩之前拔除掉。

Seems reasonable, right?

似乎很合理，對吧？

Well, it's actually a controversial topic among some in the dental community.

這實際上在牙科界是一個有爭議的話題。

The worry is that we're removing our wisdom teeth too frequently, often when it's unnecessary and the teeth pose no threat,

令人擔憂的是，通常在沒必要而且不構成威脅下，我們太頻繁地拔掉智齒。

like if your mouth is big enough or you're one of the 38 percent of people who don't develop all four wisdom teeth.

比如，如果你的嘴足够大或者你是 38% 的人中不會四顆智齒全長的其中一人，

In that case, risks from surgery like infection and nerve damage pose more danger than the teeth themselves.

在這種情況下，手術帶來的危險，像是感染和神經損傷比智齒本身更危險。

But the fact remains.

但事實依然存在。

When wisdom teeth do become a problem, you'll curse the day we invented cooking.

當智齒變成問題時，你會詛咒我們發明烹飪的那一天。