I really enjoy being a dentist, one of my big worries is who will wheel me into the operatory to work when I am 95 years old and insist on continuing to work because I refuse to retire. I enjoy fixing things, giving people a better smile, whether it be with crowns or veneers or with invisalign. There are a million other things I like that I won’t bore you with, but the thing I may enjoy the most is getting to know my patients and being able to see them every six months. Six months is usually just long enough where the event you were excited about six months prior has had time to occur and I get to hear about how it went, or wonder why my invitation to go on your cruise never came as I sat by the phone. I get to see how your new job is going, how the wedding went (again I have to ask because I was not invited) and how your honeymoon went (again, NOT invited!) As the six month visits add up over time I see kids grow up, go off to school and maybe get married. At times we use this information to our benefit, if a patient is about to be a new grandparent we know to schedule an extra 15 minutes for baby pictures. Not to look at the pictures, but for the new grandparent to find the pictures on their phones. You may laugh, but you can count on the new grandparent inevitably looking for these pictures convinced the harder they push on the screen the more likely the desired pictures will appear.
There is bad with the good however, people worrying about upcoming cancer treatment or talking with patients after their long-time spouse has passed away or having to listen to their half-hearted excuses of why I wasn’t invited to their family reunion. While I do like to think I am a delight to talk to, many patients think I am charging them for the five minute discussion and bad jokes that occurs every six months. This is not the case. If you recall I do also take a look at your teeth to ensure they continue to be in upstanding condition. It is during this exchange that one of the least enjoyable things about my job occurs, as we discuss any potential treatment, whether it be a filling, a crown or the need for a possible extraction I will do my best to explain: 1. What needs to be done 2. Why it needs to be done 3. What will happen if something isn’t done. Please feel free to ask any and all questions. However, informing me that “nothing hurts” more often than not is irrelevant. There is rarely a correlation between discomfort and treatment needs in the beginning stages of dental treatment. There is almost always a correlation between discomfort and treatment needs in the more advanced stages of dental treatment. In those cases you are telling me what is hurting and what must be done. Well, if you don’t want to listen to my advice unless it hurts, but when it hurts you can tell me exactly what the problem is, why do you need my input in the first place? The point is just because something doesn’t hurt, doesn’t mean it isn’t currently a problem and doesn’t mean it won’t become a much worse problem.
Why is it too late to address it once it starts to hurt? (Nerd Alert DEFCON-1)
Here is a cross-section of a tooth that shows where the nerves are located. We all have gotten our hair cut and know that doesn’t hurt, why? There are no nerve endings in our hair. Well as it turns out there are no nerve endings in the enamel of our teeth as well so you will not feel a cavity if it is in the enamel of the tooth. The layer under the enamel of your teeth is called the dentin. Now this layer does not have nerves in it either, however once a cavity progresses to this layer that is when you feel the characteristic sensitivity with it.
Why? Something referred to as the “hydrodynamic theory” (It is imperative you put your fingers around your eyes like they are glasses and say it in a nerdy high pitched voice).
Basically in the dentin there are little channels with water in them and when the water goes up and down the channels it causes the nerve in the pulp to become irritated. Hot and cold temperatures, as well as air being blown on the tooth or sucking in air through your teeth, will cause sensitivity because those things cause the air to travel up and down the tubules.
Sweets or anything really concentrated, like orange juice, will also cause water to travel up and down the tube to even out the concentration gradient by diffusion. Why am I even typing surely everyone has stopped reading now……..
This discomfort is different than your classic “toothache” pain. That pain is due to the decay (bacteria) extending all the way into the nerve, causing an infection on the outside of the tooth which then can press on the nerve of the tooth and potential swelling.
Now what about those times when I have sensitivity on my teeth, but I don’t have a cavity Mr. Know-It-All? A great majority of that sensitivity can be attributed to the root surface being exposed and that occurs because there is no protective enamel layer on the surface of the root, it is just dentin covered by a very thin protective layer called cementum. Generally, it is not too much of an issue because the gums cover the root surface, but if they have receded the exposed root surface can be sensitive for a short time. It is this root surface exposure that causes that feeling we all experience when we bite into really cold ice cream. Now the ice cream headache? That is just your garden variety case of sphenopalatine ganglioneuralgia of course. Clearly a topic for another day.
So now that we understand discomfort or pain has little or no association with the likelihood of having a cavity until the decay has gotten all the way through the enamel of the tooth and into the dentin, you can now understand the frustration when a patient has a cavity and they reply with, well that is weird, I don’t feel anything. That is essentially saying things such as…..
Cardiologist: Sir your heart is 99% blocked, we need do have open heart surgery.
Patient: I don’t feel anything, it is probably fine………….
Mechanic: Sir you need new brakes yours are well past needing repair.
Driver: Well, when I push them they still work, I will wait until I can’t stop anymore.
Doctor: Congratulations you are pregnant.
Patient: I don’t see a baby yet so I am probably fine.
Husband: Honey, you seem upset;
Wife: I’m fine.
(actually at this point it is probably too late)