Cavities. Everyone’s heard of them. Everyone fears them. But does anyone really know the truth about them?

Here’s a hint, it has nothing to do with sugar bugs. But there’s way more to it than that so let’s get down to the basics before your imagination runs too wild.

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Cavities—the Fundamentals

Wait, we’ve already gone too far. Let’s start with enamel. Enamel is the irreplaceable outer layer of your teeth that protects the soft layer below it. It’s your teeth’s natural shield and it’s even stronger than bone. But once it’s gone, it doesn’t grow back. So for the love of all things dental, take care of it! (Not to worry, we’ll tell you how if you keep reading.)

Cavities all start in that good ol’ enamel. In fact, by definition, cavities are the destruction of tooth enamel. Simply put, they’re a hole in your tooth. They can form in many places, but they typically form on the top of your back teeth. See, when you bite down, food gets stuck. If that food is sugar, it’s particularly bad news—we’ll come back to that too. So long story short, they’re permanent damage to your teeth. But don’t freak out just yet—that’s why we have dentists.

A Game of Tug of War*

But why would enamel just randomly break down? Valid question. It’s primarily because of what you eat. But again, we’re getting ahead of ourselves.

First, let’s talk about plaque. Plaque is basically just a sticky film that easily adheres to your teeth, especially in the grooves of back teeth and along your gum line. It contains bacteria that feed on sugar. This process creates acid that eats away at enamel. So like we said, it’s about what you eat—sugar. And the more of it you eat, the more your enamel is exposed to acid, and the more likely you are to get a cavity. Think of this process as team “Bacteria + Sugar.”

But, there’s another team in this game of tug of war: “Saliva + Fluoride”—also known as the good guys. Let’s start with saliva. Saliva, aka spit, slobber, or drool, is loaded with calcium and phosphate and bathes the teeth to keep them strong. As if that’s not good enough, it also reduces the acid (from team “Bacteria + Sugar”) by washing away the sticky, sugary foods attached to your teeth via plaque. In other words, it weakens the acid and helps repair your teeth.

Part two of this team is salvia’s sidekick, fluoride. Fluoride comes from toothpaste, water, and other sources. Together, saliva and fluoride form team “Replacing Minerals Lost During an Acid Attack to Help Enamel Repair Itself.” But that’s not very catchy. We’ll stick to team “Saliva + Fluoride.”

Stopping the Sugar Monsters

Good news is you can be part of team “Saliva + Fluoride.” See, you’re a superhero too. How? First, brush your teeth twice a day with a fluoride-containing toothpaste. It helps, you guessed it, to increase the amount of acid-fighting fluoride in your mouth. Second, drink a lot of water to increase the amount of (also acid-fighting) saliva you produce. Go team!

But it doesn’t stop there. Truth is, helping your natural cavity-fighting team really just comes down to good oral health habits:

  • We said it once, we’ll say it again—brush twice a day with fluoride-containing toothpaste. Since saliva production decreases at night, make sure one of those times is right before bed.
  • Clean between your teeth daily with floss, Waterpik, or another interdental cleaner. This removes food particles and prevents plaque buildup—both big “Bacteria + Sugar” supporters.
  • Eat a healthy well balanced diet rich in vitamins and minerals. Your whole body will thank you for this one!
  • Cut down on snacking. Grazing on sweet snacks or sipping on sweet or acidic drinks throughout the day is the number one cause of cavities. With every bite and every sip you cause a whole new acid attack in your mouth.
  • Get a dental exam and cleaning every 6 months. When the dentist cleans your teeth, it’s not just a normal brushing. They’re actually removing dental plaque, checking for any areas of early tooth decay, and even applying a fluoride gel or varnish if necessary. This can prevent cavities from forming and even curb ones that are underway.
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Fixing the Damage

These days, having a cavity isn’t as scary as it sounds, because they’re treatable! (We know, best news yet!)

  • If a cavity is still in its early stages, it can often be repaired with remineralization treatments. Dentists use rinses, pastes, coatings, or filling materials that contain fluoride, calcium, and/or phosphates to fix, or even reverse, a cavity if it has just begun to form.
  • If the cavity is a little further along, that’s okay too—dentists are miracle workers. In some cases, they can completely remove cavities and fill in the hole with silver amalgam or a white-colored composite material that will keep the tooth strong and healthy. That’s called a filling.
  • In some cases, fixing a cavity may call for more complicated treatments like a crown, a root canal, or even an extraction.

And there you have it—the lowdown on all things cavities. Ready to start or improve your anti-cavity journey? Visit your MDA dentist or find one at

* All “Tug of War” references originated with The National Institute of Dental and Craniofacial Research (NIDCR) as seen​ here.