How Cavities Form
So many patients feel anxious about their regular dental visits, in part because they’re nervous they might have a cavity. How can you know for sure if you have one or not? Dr. Anderson and our whole team here at Anderson Family Dental believe that education is essential to helping you feel empowered to take charge of your oral health. That’s why we’re going to break down exactly how cavities happen and what you can do to prevent them.
Understanding Cavities Means Understanding Healthy Teeth
Before we get into how cavities form, it is helpful to understand the structure of healthy teeth. While it may seem like your teeth are just little white rocks, they are composed of multiple, highly organized layers of different types of minerals.
The outer layer is what most of us are most familiar with. Enamel is the incredibly dense outer layer of the top of the tooth, the part we can see with our eyes. Enamel is made of a complex of a few different minerals, mostly calcium, joined by super strong bonds that create a new mineral called hydroxyapatite. It may be fairly thick or very thin depending on what type of tooth you’re looking at, as well as how worn the tooth has become. Hydroxyapatite is found in bone minerals throughout our skeleton, but enamel has the highest concentration anywhere in the body. The crystalline structure of this mineral makes it resistant to breakdown. Which is a good thing because we really put a lot of wear and tear on our teeth compared to other bones!
However, the enamel does not cover the entire outer layer of the tooth. The root of the tooth, the part hidden by the bone socket and gums, is covered in a very thin, more fragile type of tissue called cementum. Cementum is a little less dense than enamel because it helps grab onto the ligament that keeps the tooth in place.
Inside the shell of enamel and cementum, is dentin. Dentin is much weaker and more porous than enamel. The dentin makes up the bulk of the tooth and almost has a sponge-like structure. Inside all these microscopic pores called tubules that run through the dentin, you can find tiny hair-like branches of the nerve that gives that tooth its ability to feel. Those tubules are the key to tooth pain (more on that later).
The deepest part of the tooth is the pulp. That’s where the nerve and blood supply for the tooth sits. Damage to the pulp of a tooth is usually a very serious problem. The blood vessels here can even carry untreated infections to other parts of the body and lead to life-threatening problems. If an infection or injury touches the pulp, it usually needs to be treated as an emergency.
How Does Decay Start?
With very few exceptions, cavities work their way into the tooth from the outside. But isn’t that super dense enamel meant to resist cavities? Yes, but it’s not invincible!
The primary cause of decay is acid exposure. This acid can come from a variety of places, but most cavities will be the result of acid from bacteria. The bacteria in your mouth eat the same foods you eat and digest them. Once they’re done digesting, just like you, they create waste. That waste is acid.
Acids from bacteria and food damage the bonds between the mineral molecules in the enamel. A couple of broken bonds aren’t a huge problem and can be repaired by the mineral in your own saliva, helped along by fluoride in your toothpaste and drinking water. However, if you let bacteria and acid sit there without cleaning it off and repairing the mineral, the enamel becomes softer and weaker.
Slowly, that acid will eat its way through the enamel and eventually reach the dentin.
Does Every Cavity Need a Filling?
Sometimes, no! Damaged minerals in the outermost layer of the enamel may be okay to just watch, provided you are diligent in your flossing and brushing, and you use good fluoride products. Sometimes we are able to stop this type of damage before it can become a true cavity!
However, if the decay does continue to progress and reach the dentin, we will have to treat it. Why does dentin make the difference? Remember those tubules we talked about? The structure of dentin allows bacteria and acid to travel easily further into the tooth. Left untreated, it will reach the pulp and cause injury to the blood and nerve supply to the tooth. From there, the bacteria can wreak havoc. Lucky for you, Dr. Anderson and the Anderson Family Dental team are here to make sure your teeth stay healthy and treat any cavities long before they reach that point.
Don’t let anxiety about cavities weigh on you. Get on top of those great home care habits and call us today to schedule a dental health check-up!