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What is a Dental Cavity, Root Canal, and Filling?

If you are Googling this, you’re probably wondering what is a dental cavity and what is a dental filling? That is what I’m going to explain now!

Dr. Nathan here at Thrive Dental and Orthodontics, and I want to review what a filling is and why you may need one. I’m also going to go over the difference between a filling and a root canal. 

What is a cavity?

All right. Let’s get to the basics. What is a cavity? What happens is you’re eating all this food,  mainly sugars, and you have bacteria in your mouth, and the bacteria is also on your teeth. I don’t care how much Scope or Listerine or whatever you’re swooshing with. You still have bacteria in your mouth and around your teeth. Also, you should probably not be using Listerine every single day, but that’s for another story.

So you have bacteria that is on your teeth, and you ingest all this sugar. The sugar itself isn’t necessarily eating the tooth, and the bacteria itself isn’t necessarily eating the tooth, but what happens is the bacteria take in all this sugar, and the byproduct of it going through the bacteria is an acidic substance. That acidic substance is the thing that will gently and slowly, over time, erode your teeth. It’s not like the bacteria themselves are eating away at your teeth. It’s the byproduct of the sugar that gets processed by the bacteria to become this acidic substance, which over time demineralizes your teeth.

Now, this process doesn’t take a day or two or three. The cavity forms over time. That is why with proper brushing and flossing, and rinsing, you will not get cavities.

What are things that can prevent you from getting cavities? 

One of our leading causes of cavities is the type of bacteria we get passed down from our family. Some people just have stronger bacteria that are less prone to giving you cavities. This means that getting cavities is somewhat a genetic or familial predisposition. Some people are just genetically predisposed to getting more cavities, but if you have excellent oral healthcare, which means brushing at least two times a day for two minutes, flossing every single day, and maybe using any additional tools that you need to use, you are going to have less or potentially no cavities because your oral health is so good.

So think about this. If the sugar gets on your teeth,  which, let’s face it, everybody will have a little sugar here and there. If you’re brushing and flossing properly, that sugar and the acids that are produced and bacteria are going to get washed away. But, if you’re not brushing and flossing correctly, that acid’s going to stay on the tooth, and it’s eventually going to erode it away. As the days, weeks, months, and years go by, that acid on the teeth slowly gets into the enamel and dentin. If it removes enough of the tooth structure and becomes visible, it is now called a cavity.

Now here’s where it gets a little scary and a little dangerous. The outer surface of our teeth is made of enamel, and that is one of the strongest substances in our body. The enamel is meant to withstand massive forces, bacteria, and mild acid. Once the acids get far enough and it eats away at the enamel, they will get to the second layer of the tooth, the dentin.

Dentin is an organic substance that is definitely not nearly as strong as enamel, and it’s quite porous. Once the acids and the bacteria hit that level, they’re going to spread like crazy. So once you get into the dentinoenamel junction, the bacteria and the acid spreads, and it can damage your teeth.

What is the difference between a cavity, a crown, and a root canal?

We are now at the point when the bacteria has spread from the enamel to the dentin. What’s underneath the dentin? Underneath the dentin is a pulp chamber where there are nerves and blood vessels. The pulp chamber is the lifeblood of the tooth. If the bacteria and the acids go beyond the enamel, beyond the dentin, and they get close to or in the pulp, that is going to create a ton of pressure and inflammation, and the inflammation has nowhere to go. The pressure builds up and can create tons of tooth pressure and pain. If the bacteria and the acids get to that level, if they get to the pulp chamber, to those nerve and blood vessels, or very close to it, you’re likely going to need a root canal.

So this is what happens. You come in, and you have these medium-sized fillings, and we say, “Hey, we need to take care of it before it gets bigger,” but due to time, finances, whatever it is, you decide to wait till the next visit. What happens is that next visit, that cavity that was medium-sized now has gotten huge because it got to that dentin layer and spread like crazy. 

Now, instead of just being filling, it becomes a root canal, and a root canal is when we drill the tooth, and we take away the nerve and the blood vessels because it is infected, and there’s no real way to cure that without taking off those nerves and blood vessels. That’s the difference between a cavity and a root canal. When you get a root canal, you will likely need a dental crown because much of your tooth structure will be decayed. If too much is decayed, then a normal filling won’t hold the tooth together. 

A cavity is when the bacteria and the acids have not reached that inner portion or even close to that inner portion. A cavity is when the bacteria is still mainly on the outer surface, and we can prevent it from getting worse.

So i know what you’re thinking, “hey, can i just reverse a small cavity? Can i just take some fluoride, and i’ll be good?”

Well, if it’s very small, you can actually reverse a cavity, but they have to be super small, and your oral habits have to go from being pretty decent to absolutely perfect, but it is known to happen. If the cavity has reached that junction, between the enamel and the dentin, you can’t really fix it on your own. That’s when you need a filling.

You now know what a cavity is, so how do we fill a cavity? 

We don’t really use amalgam or silver fillings anymore because I think they’re just a little dangerous. They have mercury and all these substances that we don’t like to use anymore. We use something called composite, and that’s just a couple of chemicals mixed that solidify and get hard and look fantastic. They look exactly like your tooth structure. Many people have fillings, and you can’t even really tell what it is.

All right, guys and gals, there you have it. That’s the difference between a cavity and a root canal. Now, you know how you get a cavity, and remember to prevent it, try to eat fewer sugars, and if you’re eating sugars, eat them less frequently. If you’re eating sugars or drinking sugars, you definitely want to rinse with some water or something that is going to make it, so your pH level doesn’t get so acidic.

Remember, if you have a cavity, try to get it fixed before it becomes a root canal because when it becomes a root canal, it is just so much more difficult to treat because not only do you need the root canal, but you also need a crown.

Thanks for reading, everyone. Dr. Nathan here at Thrive Dental and Orthodontics. Remember, I’m putting out videos every single week, so leave your questions and comments below, and I’ll do my best to answer them.

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