TODAY'S PAPER
67° Good Morning
67° Good Morning
NewsHealth

HOW COME? Getting to the root of wisdom teeth

Why do we get wisdom teeth, if we don't need them? asks a readerUntil we turn 18 or so, it seems like our mouths are done growing new teeth. The baby teeth are long gone, replaced by 28 "adult" teeth. There are the incisors, the four front teeth on top and bottom, bracketed by four pointy canines (the "vampire" teeth).

Next come the eight flat "premolars." And, finally, the eight molars -- the grinding experts -- bring up the rear.

The full set equips us to chomp, tear, and grind food, and even helps us speak. Our lips and tongue work with the helpful wall of teeth to create the sounds of consonants, such as "f," "v," "s," and "z."

Then, suddenly, just as we're leaving high school or entering college, bam: new teeth. Just beyond the molars, in the back of the mouth, a new set of molars has been stealthily growing. These "third molars" sprout in the mouth's far corners.

But the wisdom teeth have appeared right on schedule. We get our first set of four molars around the age of 6 or 7, and the second set erupt at age 12 or 13. The third molars begin to appear from ages 16 to 21, with most people noticing them around age 18.

(The final molars are called "wisdom" teeth because they appear just about the time we are fully grown, and have supposedly achieved adult wisdom.)

Most people get four wisdom teeth, but some get fewer. And an unlucky few may find themselves with six new molars. And unlike other teeth, which arrive and get straight to work chewing without any trouble, wisdom teeth usually arrive with built-in problems. These molars often grow in at odd angles, or jut only partially out of the gum. Wisdom teeth may even stay stuck under the gum.

A partially erupted tooth may trap food (and bacteria) under the top of the gum; angled teeth may damage the molars next door. So dentists often recommend pulling wisdom teeth, and most people in the United States eventually have them removed.

A note to our community:

As a public service, this article is available for all. Newsday readers support our strong local journalism by subscribing.  Please show you value this important work by becoming a subscriber now.

SUBSCRIBE

Cancel anytime

If the third molars are so much trouble, why do we have them?

Early humans had much larger, heavier jaws, with ample space for 32 full-sized teeth. (In fact, Neanderthal jaws were so large that even the wisdom teeth had a gap behind them.) And all those molars came in handy for patiently grinding down rough, natural foods.

But as humans evolved, their bigger brains required more skull room, and jaw size gradually shrunk over time. So when the final four finally arrive, they find their promised parking space long gone.

A note to our community:

As a public service, this article is available for all. Newsday readers support our strong local journalism by subscribing.  Please show you value this important work by becoming a subscriber now.

SUBSCRIBE

Cancel anytime

Health