Good dental care is important. Studies have shown that tooth problems are significant factors in school absence. The Centers for Disease Control and Prevention estimates that 164 million work hours are lost each year to dental issues. Dental-related emergency department visits are on the rise in the United States, contributing to health-care cost increases.

But if you're shallow and vain, like me, there's a far more compelling reason to keep those twice-yearly dental appointments: if you don't, your teeth will literally fall out of your head.

On Thursday, Gallup released state-by-state numbers on frequency of dental visits in the United States. "For the third year in a row, Connecticut residents were the most likely [74.9%] to say they visited a dentist in the last 12 months," Gallup writes. "Just over half of the residents in Mississippi say the same, coming in last for dental care among the 50 states." If you're familiar with the general geography of health and well-being in the United States, the map isn't terribly surprising -- states in New England and the Northern Plains had the highest rates of recent dental visits, while the lowest rates were found in, you guessed it, the south.

But these numbers become terrifying when you correlate them with the percentage of seniors in a given state who are missing all -- yes, ALL -- of their teeth. States where people don't go to the dentist also have the highest rates of elderly toothlessness -- as high as 36 percent in West Virginia.

Naturally there are a lot of factors at play here, income and poverty being chief among them. And there's one major confounding factor that this chart doesn't show -- fluoridation. The CDC notes that the baby boom generation "will be the first where the majority will maintain their natural teeth over their entire lifetime, having benefited from water fluoridation and fluoride toothpastes." Mass fluoridation of municipal water supplies didn't happen until 1945, when Grand Rapids became the first city to do so. So the seniors in the chart above didn't receive the full benefit of it over their lifetimes.

Still, plenty of people lose their teeth even with fluoride. In 2002, the Department of Health and Human Services estimated that nearly a quarter of Americans in their 40s had fewer than 21 teeth (for reference a full set of teeth, with wisdom teeth removed, is 28). Water fluoridation is a necessary, but not sufficient, condition for maintaining optimal oral health. Good brushing, flossing, and dental care are also required.

So the next time you think about skipping your dental cleaning think about the chart above: You don't want to end up at the wrong end of that trendline.

Hat tip to the Post's Catherine Rampell on the Gallup data.