It sometimes feels like wisdom teeth only exist to get impacted, cause problems, and generally increase the potential for mouth misery. So why oh why are they still there?
Are wisdom teeth vestigial?
Yes, but then again no. Vestigial structures are generally classified as things useful for the survival of our ancestors but of no use today. While it is certainly true that some people need to have them removed, some don’t and their wisdom teeth perform their job of grinding down food. And anyone who has lost a molar but not their wisdom teeth is probably pretty happy for that extra chewing power.
So why don’t they fit?
Our jaws haven’t gotten smaller genetically. Bones we use more grow larger. Ancient man ate lots of hard seeds, nuts, and uncooked foods requiring lots and lots of chewing. And their food wasn’t as clean as today’s supermarket variety, thus they also worked their way through dirt and sand. Their jaws got quite a workout, thus developed more fully. Now we eat processed and cooked foods, soft in comparison, but if our diet changes again and we chew more, our jaws would grow larger once again, making more room for those chewing helpers, wisdom teeth.
The other reason wisdom teeth don’t have room is actually good dental hygiene. The loss of permanent teeth at a young age used to be common. Tooth decay, gum disease, and heavy abrasion from tough, unclean food all contributed to a much higher percentage of tooth loss, or teeth so ground down they took up much less space. So one could look at wisdom teeth as a cleverly delayed set of spares, arriving in our late teens or 20s to replace those worn out after 15 years of hard work.
With the advent of electronic toothbrushes, fluoride in the drinking water or table salt, dental floss, and regular trips to the dental clinic for a clean and check, we keep most of our teeth. And we use those teeth on cooked chicken, yoghurt, soft fresh breads, and generally wash the dirt and sand off first, all of which mean our jaws don’t grow quite so large. Thus we’re left with too many teeth in not quite enough mouth.
So, if you do have problems with your wisdom teeth, pat yourself on the back for maintaining such good oral hygiene and eating such wonderfully healthy food. And if a zombie apocalypse ever does send us scampering into the hills, we’re going to be very glad those wisdom teeth are still there.