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Why Do Wisdom Teeth Suck?
관리자 2021-05-11 오후 1:54:14 772

 

Description: 

Every year, 5 million Americans have their wisdom teeth removed. These pesky 

molars can cause infections tooth decay, and even tumors. The problem? 

Wisdom teeth often can’t fit in our mouths. But that wasn’t always the case.

Early human ancestors used these teeth to grind up tough, uncooked food. 

 

Transcription:

Each year, five million Americans get their wisdom teeth removed, which costs

about three billion dollars in total medical costs. But for many, it's worth it, since

leaving them in can cause serious problems like gum infection, tooth decay, and

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

today. Wisdom teeth have been around for millennia. Our ancient ancestors used 

them the same way we use our other eight molars: to grind up food, which was

especially handy before the advent of cooking around seven thousand years ago,

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

to chew. 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. But here's the problem:

The genes that determine the size of our jaws are completely separate from the 

genes that determine how many teeth we grow. So as our jaws shrank, we still 

kept all 32 teeth. And it eventually got to the point where there wasn't enough 

space to fit all of the teeth. But why did wisdom teeth specifically get the boot? 

Well, they're the last to show up to the party. Wisdom teeth don't usually grow

in until you're between 16 and 18 years old. And by that time, chances are your 

other 28 teeth have taken up all the available space in your mouth. In that case,

instead of growing in like a normal tooth wisdom teeth get trapped or impacted in

your jaw, which often makes them grow in at odd angles and press against your 

back molars causing pain and swelling. It also forms a narrow crevice between the

teeth creating the perfect food trap. 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. But it gets worse. Tooth decay can eventually 

destroy your wisdom tooth. So, to save you and your teeth from such a horrible

fate, dentists will often remove wisdom teeth before they go rogue. 

Seems reasonable, right? Well, it's actually a controversial topic among some in 

the dental community. The worry is that we're removing our wisdom teeth too

frequently, often when it's unnecessary and the teeth pose no threat, 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. In that case, risks from surgery like infection and nerve 

damage pose more danger than the teeth themselves. But the fact remains.

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

 

Questions: 

1. Why did our jaws shrink? 

2. How many teeth do humans have?

3. Explain why do wisdom teeth is awful?


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