How Cavities Form and What You Can Do to Stop Them

What is a Cavity?

Interviewer: Cavities are one of the most common health problems and one of the most misunderstood. They don't appear overnight. They develop through a process that starts long before you feel any sort of pain.

To explain what's really happening, we're joined by Dr. James H. Bekker. He's a pediatric dentist at University of Utah Health. Dr. Bekker, what exactly is a cavity? What's going on in the tooth when we get this thing that we call a cavity?

How Bacteria, Sugar, and Acid Team Up Against Tooth Enamel

Dr. Bekker: Cavities are a process that happens in your mouth. Everybody has bacteria, naturally occurring bacteria in their mouth. And in the presence of certain foods, certain environments, those bacteria produce acid. And the acid then eats away at your tooth. And so simple formula: bacteria plus sugars produce acid. And so the acid then goes on to cause a cavity.

So we just have to interrupt that process. Now, why have we been able to put a man on the moon, but we can't stop cavities, right? This has been a long, long-standing question. Well, it's because if you try and wipe out one bacteria that causes the acid, another one hops in and takes over. And you can't wipe out all bacteria because bacteria have a beneficial effect on many processes of our body.

Sugar Exposure Matters More Than Sugar Amount

So what we have to do is we have to interrupt that process of producing acid. So you evaluate your diet, you evaluate your habits, and you see what you can do to minimize the amount of acid in your mouth. An interesting thing, you could take 12 candy bars and eat them all simultaneously, one after another, and get them all down in 2 minutes. That would have less of a cavity-generating effect than one lemon drop that you suck on for 20 minutes.

Interviewer: Okay.

Dr. Bekker: Because it's not the amount of sugar, it's the exposure of sugar to your enamel. That's why things like sugary drinks are so hard on your teeth, because you sip them over and over and over throughout the day. So the exposure of the sugar to the bacteria creating the acid is longer. So to fight cavities, we simply fight that process.

Factors That Make Some People More Prone to Cavities

Interviewer: I've got a question. So are some people more prone to cavities than others? Are there some factors that increase risk beyond, well, the diet? You're probably going to talk about that again, like if you've got a soda drinker versus a non-soda drinker, that person is probably more prone. But are there some other factors that contribute, genetically or otherwise?

Dr. Bekker: Absolutely. I have seen children who do everything wrong and don't get a cavity. I've seen children who are pretty diligent, and they still get cavities. And it's just because of the makeup of the acid in their mouth, the saliva, how acidic is your saliva? And some people definitely are more prone to getting a cavity.

How Brushing and Flossing Interrupt the Cavity Process

Interviewer: So we all know to brush and floss. That's really important. Talk about how that helps prevent those cavities. I would imagine it has something to do with disrupting that process of acid-forming on the tooth enamel and eating it away.

Dr. Bekker: Exactly. And so the key is thinking about the exposure of acid onto your tooth. Brushing and flossing reestablishes and takes away the acid on the surface, taking away that process. So you do that ideally in the morning after you eat and at night before bed to have a couple of times a day where you re-establish that strength for your teeth. But then the rest of the time, you're cognizant of how much acid you're exposing your teeth to. If you have a soda drink, maybe you go to the drinking fountain after, and you swish your mouth with water and get some of that acid off of your teeth, that kind of thing. So brushing and flossing and then minimizing acid exposure during the day.

Everyday Habits and Foods That Increase Cavity Risk

Interviewer: Right. Being aware of what am I doing right now? Could it be creating acid on my teeth? And how could I disrupt that? And it could just be as simple as drinking some water after a meal or after a candy bar or after . . . You probably would tell people never to suck on a lemon drop, I'm guessing. That would probably be your advice.

Dr. Bekker: No, but if you do, I mean, just get some water, rinse your teeth off, and get that sugary coating off of there.

Interviewer: So diet is pretty critical to whether or not somebody is going to get cavities. The makeup of the saliva.

Dr. Bekker: Huge.

Interviewer: Yes, the makeup of the saliva. So, genetics or the individual, it sounds like, brushing and flossing. Are there other habits that might unintentionally raise cavity, drinks?

Dr. Bekker: Anything that's sticky that gets on your teeth and sticks to them is going to be more cariogenic, we say, or causing cavities. So staying away from sticky things that adhere to your teeth, that's another thing you can do.

Early Cavity Warning Signs

Interviewer: So, when it comes to cavities, what sign should people watch for that might indicate a cavity? And I mean, this could be a duh question. I would imagine some pain, you know, but are there other things that could help somebody find it quicker?

Dr. Bekker: Definitely pain and even just sensitivity. If a tooth is more sensitive, there are lots of surfaces of the tooth in between. A tooth has four surfaces and a chewing surface, four sides. So it might be a place you can't see. But if you have sensitivity, have it checked. Bleeding around the gums is another really important thing because the supporting structures of your teeth, the gum tissue around your teeth, are very important. And if you have gum disease because you're not getting the bacteria cleaned away, your gums recede. And then it's the surface of the root that is exposed, which is more susceptible to getting a cavity because it's not hard enamel like the crown of your tooth. So if you have some gum disease, it'll show up with some bleeding, that's a red flag. You need to have that looked at and checked. So pain, bleeding, sensitivity, any of those things.

Dental Visits Help Prevent Cavities

Interviewer: And how often should I be seeing my dentist, getting dental exams, to optimally prevent cavities?

Dr. Bekker: Twice a year.

Interviewer: Okay, that was an easy answer.

Dr. Bekker: I was just going to say some people, if they have advanced gum disease, will need to be there every two or three months having some treatments to get them into a position of health, or if a high cavity rate, you might want to be checked a little bit more. But for a regular person who is taking good care of their teeth, twice a year is recommended.

What to Do If You Keep Getting Cavities Despite Good Habits

Interviewer: I want you to take a moment and pretend that I'm a patient who's come in and I seemingly do most things right, but I tend to get more cavities than somebody else. What advice do you have for me to try to . . . What additionally can I do to try to control that situation?

Dr. Bekker: So I would say let's talk about your diet. Let's talk about what you're eating that is causing more sugar in your mouth. Let's talk about your general health. Do you have any conditions that are causing dry mouth? Are you having radiation therapy? Are you a cancer patient? What's your diabetes situation like? Any of those conditions can lead to more dental decay. So I would just sit you down and evaluate you specifically on all those factors and find out what it is that's causing the decay, and then take some steps to enhance your prevention.

Interviewer: As we wrap up, what's one thing that most people get wrong about cavities?

Dr. Bekker: I think one thing that most people get wrong is that if I ignore it, it's going to go away. A cavity will never go away. It only gets worse. So at the first sign of sensitivity, of pain, get it checked out. The solution is always better if you catch it early.

Interviewer: And finally, what's one small step that somebody could take today to improve their dental health and their chance of not giving cavities?

Dr. Bekker: Scot, among the dental community, we have a saying: only floss and brush the ones you want to keep.