Dental MythBuster #12 – I can’t have a cavity because there is no hole in my tooth!

This Dental MythBuster is slightly unfair, as it relies upon the slang term cavity that has been used for decades. However, it is still a myth, and like all dental myths, this myth needs to be identified and busted!

Let’s start by looking at a photo:

high res photo showing teeth with dental decay but not cavities

Photo showing decay on front teeth but no “cavities” present.

If you look at the above photo, everyone would agree that something is not right. The brown/grey areas where the teeth touch one another look awfully suspicious. When I informed this patient that she needed fillings with those teeth, she looked at me perplexed and said “Why… I can’t feel any cavities there?!?”

I hear this dental myth about once per week in my office. Once I show either an x-ray or photo of the cavity, they understand immediately. Wouldn’t you if you saw the above photo?

Cavities, Caries, and Decay

Part of the reason why this dental myth exists is because there is some confusion and misuse of various dental terms. And we dentists are part of the problem! Let’s look at definitions:

Dental Caries – also known as dental decay, this is an infectious disease leading to the progressive destruction of tooth structure. This is seen in the photo above.

Dental Cavities – a carious lesion or hole in a tooth. Although this term is used quite often, it is generally considered to be a slang term.

So, what does an actual dental cavity look like? See below:

photo showing teeth cavities visible in the actual mouth

Two cavities present. In this case, there are actual holes in the teeth!

In the above photo, you can see actual holes in the teeth. These are areas of dental decay that have progressed to the point where the tooth surface actually collapsed in, creating a cavity. This patient was actually able to feel and see the cavities.

Another Dental Myth Goes Down

So far, we’ve seen two photos: one showing decay without holes and one showing decay with holes.

In both cases, the patients required fillings and/or other work to restore. I don’t think anyone would disagree with that.

So, let’s dispel this myth with this simple statement:

Dental cavities can be present with our without actual holes in your teeth. You don’t need an actual hole in your tooth to need a filling.

So if your dentist tells you that you have decay (or cavities) and you can’t see or feel a hole, it doesn’t mean there is no cavity. It is definitely there. Ask your dentist to show it to you on an x-ray or have him/her take a photograph of it. I do it all the time.

I hope you enjoyed this post. I’m already working on Dental MythBuster #13!

Dental MythBuster #11 – You can get Gum Disease from Kissing Someone

Photo of people kissing and getting gum disease

Is he about to give her gum disease?

This dental myth is not as common as some of the other ones I have seen, such as the novocaine myth, the epinephrine allergy tale, and many others. However, it is still something that I encounter on a fairly regular basis.

This myth is the belief that gum disease can somehow be caught by kissing someone who already has the disease.

What is gum disease?

Gum disease, more formally known as periodontal disease, are a series of conditions that affect the gum and bone tissue holding in the teeth. While there are some uncommon variations, the most common types are gingivitis and periodontitis.

Without proper treatment, over time, the disease can destroy the tissue holding in the teeth. And as a result, the teeth can ultimately loosen up and/or become infected, resulting in the loss of those teeth. Note that this is a completely different disease than cavities (also known as dental decay or caries).

Causes of Gum Disease

A photo is worth a thousand words, so let’s take a look:

Photo of lower teeth with significant calculus (tartar) and gum disease

Lower front teeth being viewed from the tongue side. Calculus, aka tartar, has built up between the teeth leading to gum disease.

The above photo shows the #1 cause of gum disease: poor oral hygiene leading to a buildup of plaque and calculus on the teeth above and below the gums.

This patient is one I saw in my office in Orange, CT. His gums tissue was red and inflamed and would bleed whenever they were touched.

Besides oral hygiene, there are other factors that can contribute to gum disease:

  • Smoking
  • Certain medical conditions such as diabetes, HIV, leukemia, and many others
  • Some medications that cause dry mouth
  • Certain genetic traits
  • And many other factors

What’s Love Got to do with it?

Inflamed gums leading to periodontal disease seen in Orange, CT

This did NOT come from kissing someone!

Nothing! Gum disease is not caused by kissing someone. While it is true that kissing can spread oral bacteria from one person to another, this act does not cause a person to develop gum disease.

Did the plaque at the gum line on the photo to the left come from the person this patient just kissed? No!

While it may be tempting to blame your ex for the conditions of your gums, this is one thing you can’t pin on him/her!

Until the next Dental MythBuster…


Dental MythBuster #10 – I’m allergic to epinephrine!

For this 10th Dental MythBuster, I’ve decided to tackle one of the greatest ones out there: The mythical epinephrine allergy!

Epinephrine used at the dentist photo people think they are allergic

Epinephrine for injection.

I consistently hear some variation of the following at least twice a month in my office in Orange, CT:

“Doc, for the shot, don’t use the one with epinephrine. I’m allergic to it.”

Upon hearing that, I always use a dental local anesthetic that does not contain epinephrine. But in all cases, the patient is improperly using the word “allergy.” Let’s see why.

About Epinephrine

Epinephrine, also called adrenaline, is a naturally occurring hormone and neurotransmitter in the body. It plays a critical role in the “fight or flight” response. Epinephrine has a number of different functions, including increasing the heart rate, regulating lung capacity, increasing the amount of available glucose, and many others.

Picture of epinephrine used in dentistry by dentists

Structure of Epinephrine

In addition to being naturally released by the body, epinephrine can be administered by health care providers in many situations. Epinephrine is given in many situations of acute cardiac arrest (a heart attack). It is also given in the treatment of an acute allergic reaction called anaphylaxis. It is frequently sold in an injectable form called EpiPen for those people susceptible to these types of reactions. We have an EpiPen in our office in Orange, CT as part of our emergency kit.

But the critical thing to keep in mind is that every single person produces and releases epinephrine all the time.

Why Dentists Use Epinephrine

As a dentist, I inject local anesthetic containing epinephrine at least ten times per day. Epinephrine is used because it acts to constrict the blood vessels in that area. By doing so, the local anesthetic remains in that area longer, because there is less blood flow to take the local anesthetic away. Simply stated, the epinephrine helps you feel and stay number longer.

As anyone can imagine, a dentist who does not get their patients adequately numb will soon find themselves with an empty chair! And epinephrine is a key factor in keeping patients adequately numb for procedures.

An Epinephrine Allergy?

So how can you have an allergy to a substance that your own body produces and uses every second of the day? The answer is it’s impossible! If you were allergic to it, you would be developing symptoms all the time! I won’t bore people with the technical definition of an allergy, but this is a good summary.

Carpule of lidocaine and epinephrine used by dentists in our Orange CT practice

Lidocaine with epinephrine.

So where did this myth originate? Well, most people confuse an adverse reaction with an allergic reaction. Common adverse reactions to an injection of epinephrine at the dentist can include:

  • Your heart starts to beat much more rapidly.
  • Your heart starts to beat much more forcefully.
  • The skin on your cheek – near the injection site – gets very pale.
  • You become suddenly dizzy.
  • Your shirt becomes wet from sweating (called diaphoresis).
  • You become very nervous.
  • You develop a headache.
  • And many others.

In addition, many other patients are unable to receive epinephrine due to certain medical conditions and/or medications they are taking. But this is NOT because they are allergic to it!

Dental Myth Busted!

Just like the other dental myths that I have written about (dentists no longer use novocaine, the dentist put his knee on my chest to pull my tooth, etc.), let’s bust this myth! So the next time you are at the dentist and you don’t want epinephrine, you should say:

“Doc, for the shot, don’t use the one with epinephrine. I had an adverse reaction to it.”

Until the next Dental MythBuster…

Note: since publishing this post there have been literally dozens of comments and posts which attacked me personally and/or used profanity. These comments prompted me to publish a sequel to this titled More on the Fabled “Epinephrine Allergy”. Please note that any/all comments with personal attacks and/or profanity will not be published.

Dental MythBuster #9 – You can’t get a cavity under a crown

This is one dental myth that I wish I did not have to see.  The myth typically plays out like this:

“Mrs. Jones, I can see both on the x-ray and upon clinical exam that there is decay on this particular tooth.”

She will typically respond by saying:

“How can I have a cavity on that tooth? It has a crown!”

After years of practicing dentistry, I can say that this happens about 98% of the time when there is decay on a tooth which already has a crown. So this dental myth definitely needs to be busted!

Photograph of a cavity under a crown

Seeing is believing, so let’s take a look at a photo I took of a patient in my dental office in Orange, CT.

Photo showing a cavity, also known as dental decay, under a dental crown

A cavity, known more formally as dental decay, evident underneath a crown on a lower molar on a patient of mine in Orange, CT.

The decay is visible in the above photo at the gum line. Treatment will most likely involve a new crown. Without treatment, this patient will lose his tooth eventually.

By looking at the photo, you can see that it is possible to get decay under a crown. So the myth is busted! But let’s look at how it happens.

What are dental cavities?

Dental decay photo showing a cavity on an upper canine tooth

Decay on an upper canine near the gum line.

Dental decay (known less formally as dental cavities) occurs when bacteria inside the mouth ingest certain foods and then attack the teeth. This leads to a weakening of the tooth and can ultimately lead to an actual hole (a.k.a cavity) in the tooth.

Decay can occur on any part of any tooth in the mouth. It can occur on teeth that have never had a filling before. Or the decay can start on teeth that have had fillings, crowns, or root canals.  It can start at age 2 or age 100! For a more detailed explanation, you can refer to a page I authored on my main practice website.

How teeth with dental crowns can develop decay

As stated earlier, decay can develop on any tooth. But cavities are more likely to occur in certain areas.

Dental x-ray radiograph showing decay or cavities under or below a dental crown

The red circles indicate the decay at the margin of two different crowns.

When it comes to teeth with crowns, the area most susceptible to developing decay is the margin. The margin, as you would guess, is where the crown meets the tooth. It is the weak spot. It is the Achilles Heel.

Food and other debris can collect right at the margin. A crown that was poorly made will collect even more food. If you combine this with a diet rich in sugar or acid, along with home hygiene that is not ideal, you have a perfect storm. That perfect storm affected the two crown to the upper right on the x-ray, resulting in decay.

Another Dental Myth Busted

The above photos, descriptions, and x-ray show that even with a crown, a tooth can still develop a cavity. So it bears repeating:

Crowns will protect an already weakened tooth but you still need to brush and floss sensibly. If you don’t, you can develop decay just like you would on any other tooth.