Cave Girls Had Strong Jaws, Too

Last week I enthralled you all with the 'news' that cave girls (and, not that anyone cares, caveboys), probably had better teeth than we do. Now, it turns out that "science shows" that cave girls probably had healthier jaws in general as well.

Diseases of Civilization: Malocclusion

Today, the majority of people in the US and other affluent nations have some type of malocclusion, whether it's crooked teeth, overbite, open bite or a number of other possibilities.

There are three main factors that I believe contribute to malocclusion in modern societies:

1. Maternal nutrition during the first trimester of pregnancy. Vitamin K2, found in organs, pastured dairy and eggs, is particularly important. We may also make small amounts from the K1 found in green vegetables.
2. Sucking habits from birth to age four. Breast feeding protects against malocclusion. Bottle feeding, pacifiers and finger sucking probably increase the risk of malocclusion. Cup feeding and orthodontic pacifiers are probably acceptable alternatives.
3. Food toughness. The jaws probably require stress from tough food to develop correctly. This can contribute to the widening of the dental arch until roughly age 17. Beef jerky, raw vegetables, raw fruit, tough cuts of meat and nuts are all good ways to exercise the jaws.

Before Treatment

And now, an example from the dental literature to motivate you. In 1976, Dr. H. L. Eirew published an interesting paper in the British Dental Journal. He took two 12-year old identical twins, with identical class I malocclusions (crowded incisors), and gave them two different orthodontic treatments. Here's a picture of both girls before the treatment:

After Treatment

In one, he made more space in her jaws by extracting teeth. In the other, he put in an apparatus that broadened her dental arch, which roughly mimics the natural process of arch growth during childhood and adolescence. This had profound effects on the girls' subsequent occlusion and facial structure:

The girl on the left had teeth extracted, while the girl on the right had her arch broadened. Under ideal circumstances, this is what should happen naturally during development. Notice any differences?

Clearly, we need to check some Cave Girls to  determine whether they had attractive jaws...

Nice, strong jaw...

Wombat-Socho at The Other McCain was right on schedule this week with "Rule 5 Sunday: This time It's for Real."