A Moment Of Tooth

He expects tooth regeneration "to be pretty common in the future."

Oh, but that's not the end of it.

How about genetically engineered teeth, like a shark's?

For most children, the adult teeth are there just waiting to come in at the end of the useful life of the baby teeth. But some people, it turns out, have a genetic mutation that gives them a third set of teeth, which can be induced to erupt if the adult teeth are gone. "We have some great X-rays," says dental researcher MacDougall.

Right now, that is seen as a genetic flaw to be eliminated. But some people see it as a great opportunity: We can learn how to genetically engineer extra teeth. This isn't a bug, it's a feature!

Toothful Culture

New word to know and tell: edentulous. It means having no teeth. Comes up a lot when you talk about West Virginians.

Sadly, the new world in which the CDC eventually expects all but 3 or 4 percent of us to be toothful is not arriving evenly distributed, researchers report. Poverty makes a difference, as do health education, access to quality dental care and culture.

When dental health types talk about "culture," it seems they're talking about what they find in the southern Appalachian highlands. West Virginia is not the poorest state in the union, nor is it even remotely the least educated. Yet a stunning 40.5 percent of all adults over 65 are edentulous, according to the CDC -- more than twice the national average. Kentucky is second with 38.9 percent and Tennessee third with 34.9 percent.

"Certainly lifestyle is a piece of this -- diet, exercise. On the obesity and smoking side, West Virginia ranks very, very high," says Kenneth E. Thorpe, professor of health policy at Emory University and a consultant to the West Virginia legislature on health reform. He also points to "access to early-on primary care. Low-income kids don't see the dentist ever.

"But all rural Appalachia -- it goes back to lifestyle. Lack of exercise, poor diet. Just the fat intake during the day. Cheap, high-calorie fast food is abundant. West Virginia ranks very low on nutritional markers like vegetables, fruits. The diet is very different than in California, Colorado, Utah. And then there's the lack of physical activity."

Less clear is what the story is in a place as advanced as Britain. British teeth are so bad as to have become the stuff of modern legend. In the "Austin Powers" movies, the hero's teeth are a running gag. Toothlessness among Brits over 65 exceeds that of West Virginia, reaching 46 percent, according to the World Health Organization. In Europe, this is a level exceeded only by the likes of Albania, Bulgaria and Bosnia-Herzegovina.

Plan Far Ahead

If you had been a great parent, like the University of Alabama's MacDougall, you would have saved your children's baby teeth in liquid nitrogen as sources of adult stem cells. So now MacDougall has the stem cells of her teenage sons -- Morgan, 17, and Mason, 14 -- from which to create future spare parts.

And you don't.

Slacker.

When she moved from the University of Texas Health Science Center at San Antonio to her current position in Birmingham, she took with her the liquid nitrogen apparatus containing her sons' baby-teeth stem cells. She insisted that the moving van have a generator to keep everything super-cold. And "they drove nonstop," she says.

But that's not the real test of great parenting. MacDougall didn't actually save her children's teeth in liquid nitrogen, she says. She took the teeth and extracted the soft residual tissue that holds the adult stem cells and put that in the liquid nitrogen.

Because she's the kind of mom who cared enough to give the hard part of the teeth back to the boys.

So they could put them under the pillow for the tooth fairy.