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.
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.
1. Why did our jaws shrink?
2. How many teeth do humans have?
3. Explain why do wisdom teeth is awful?