Cavity Prevention: The Anatomy of a Cavity

Maybe you're one of those people who think skipping your pre-bedtime toothbrushing routine now and then can, at worst, lead to a short lecture from your dentist. Think again. Turns out, poor oral health can be connected to a higher risk for heart and lung disease, diabetes, and—if you're a woman—having premature babies with low birth weight. Not convinced? A recent study published by the British Medical Journal determined that participants who reported brushing their teeth less frequently had a 70 percent increased risk for heart disease compared with those who brushed twice daily. Tooth decay, an obvious sign of poor oral health, is one of the most common health issues—second only to the common cold. In fact, according to the National Institute of Dental and Craniofacial Research, approximately 92 percent of adults in the United States from ages 20 to 64 have had cavities in their permanent teeth. Knowing just what the heck a cavity is and how to treat or prevent one can go far in helping keep your smile (and your heart) healthy.

The term cavity is synonymous with the word hole, which is what develops in a tooth that's not kept clean. Think of a cavity's genesis as a team effort, with you (specifically, your oral hygiene habits) in the starting lineup. Bacteria in the mouth converts food—especially carbohydrates—that you didn't brush, rinse, or floss away into acid. The acid and bacteria join forces with the remaining food and saliva to form plaque, a sticky substance that, if not ejected from the playing field of your teeth, will kick off the process of tooth decay. (If not removed, plaque can start to build up within 20 minutes of eating). Acids in the plaque dissolve your teeth's protective coating of enamel, creating holes—or cavities.

Thankfully, there are a few different ways to combat the results of this offensive drive. If the bacteria and acids have managed to create only a small hole in your tooth, your dentist will most likely "drill and fill"—that is, remove the old portion of the tooth and replace it with a filling. If the cavity is more extensive, dentists will place a cap, called a crown, over the tooth to restore it to its normal size and shape. And if the diggin' didn't stop there? The decay can spread into the tooth pulp and become infected, such that the dentist may call for a root canal. This procedure involves removing the tooth's pulp and the nerve, followed by a sealing of the roots.

New technologies are in the works to enhance the cavity detection and treatment process. Irwin Smigel, D.D.S., a dentist in New York City, mentions a detection method involving the use of a special fluorescent light that can recognize the development of decay before "it really gets into the teeth," he says. If the fluorescent-light method does indeed turn up evidence of decay, dentists can then apply sealants or utilize fluoride to prevent the development of cavities. Researchers are also working on a "smart filling" designed to slowly release fluoride in order to prevent further tooth decay in a small cavity and surrounding teeth. Although these two technologies are in the developmental stages, these detection and treatment resources could bring down cavity counts significantly over the years.

If that all sounds a bit like tactical munitions planning, here's the good news: With solid oral hygiene habits (meaning: brushing, flossing, and rinsing with a fluoride mouthwash), tooth decay and cavities are preventable. According to Nicole Holland, D.D.S., it's all about proper and consistent maintenance. "I tell my patients that what's important is your individual home care in combination with the professional care you receive when you go into the office," she says. It's a relationship between the two prongs of care. "You can't choose one or the other." Most dentists recommend you get a professional cleaning and exam every six months.

Even though we've all had it drilled into us that we should brush our teeth at least twice a day (morning and evening), many people have a tendency to skip the pre-bed brush after a long day. Guilty as charged? Heed this: As Smigel points out, brushing before sleep is the time that counts the most when it comes to cavity prevention. "During the day we swallow at least 2,000 times. Saliva in the mouth is constantly cleaning the teeth, which helps prevent cavities," Smigel says. "At night we swallow only about 20 times." An untended mouth in the evening leads not only to dragon breath in the morning, but an accumulation of plaque overnight. Holland adds that any time your mouth feels dry—for instance, after a workout or during an illness—it's important to hydrate in order to activate the production of saliva.

Don't be fooled: Those pretzel M&M's and other sugary foods aren't the only offenders. Simple carbohydrates like potato chips, bagels, and white bread are all converted into acid in the mouth. Additionally, Holland says, "It's not just what is going into your mouth; it's also the frequency. You don't want to be constantly snacking. You don't want that constant exposure to the carbs—or the bacteria will just go to town."

Addicted to chewing gum? You're in luck if what you're chomping on contains xylitol. The plant-derived substance is a sweetener in sugar-free gums and slows the growth of the bacteria that causes cavities. The American Dental Association (ADA) publishes a list of gums that bear their seal of approval.