Skeptical Thoughts From The Dentist Chair: Part I, The Questions

The Skeptical Cardiologist found himself lying in a  dentist chair one day having his  teeth poked, prodded, scraped, rubbed and polished, when fears of the adverse consequences of these procedures suddenly overwhelmed him.

Previously I had considered routine dental cleaning a necessary annoyance, something that I guiltily avoided, primarily because of the time wasted and discomfort associated with it. But as I lay with my mouth open, a series of questions erupted in my consciousness.

Perhaps this anxious skepticism was related to the writing and thinking that I have done about the downsides of routine annual electrocardiograms or routine stress testing after stents. It has become clear to me that the risk/benefit ratio of any annual medical evaluation should be questioned.

The hygienist introduced herself (we’ll call her Donna), put away her crossword puzzle book, guided me back to the exam room and told me that she was going to do an X-ray.  I wasn’t asked if I wanted an X-ray or explained the purpose of it, but dental radiography now seems to be the norm. Perhaps I am given one every time I visit a dentist because I go infrequently, much less than annually, and dental insurance tends to pay for an annual X-ray. The dental offices probably assume if it is free, no sane patient will reject it.

More and more, I have become concerned about the radiation from medical radiologic procedures (see my discussion on the radiation from coronary calcium CT scans here).

The  hygienists are always careful to put a lead apron over my groin and around my neck, which makes me feel a little better, but I can’t help but wonder…what is the yield of the x-ray in a patient with no symptoms, what is the risk of developing oral cancer from the procedure, if performed every year? And what is the probability that something will be identified that is not really a problem, which may lead to more testing or procedures?

These concerns are similar to ones that we face daily in cardiac testing (and for PSA and mammography), but unlike stress testing and breast cancer screening, there seems to be little scrutiny of the value of the routine annual dental x-ray.

Donna placed a bib around my neck and I noticed that she was wearing medical gloves and that she was preparing a device covered with plastic to stick in my mouth. That’s nice, I thought, good sterile technique! However, adjacent to the part of the device covered in plastic, was metal that was uncovered and I saw her touch that, then manipulate the plastic and put that in my mouth. 

 I began worrying about transmission of hepatitis or HIV virus from a previous patient which was now being inserted into my mouth.

I began thinking that if one case of hepatitis is created by a routine dental visit, that probably negates the benefits, if any, of the thousand patients that had their teeth cleaned and didn’t get hepatitis.

After irradiating my teeth for unclear reasons, Donna began preparing her pointy metal probes, picks, and claws for the “cleaning.”

As she began picking, clawing and scraping away at my teeth, I began to wonder if this could be more harmful for me than helpful. What if this process was somehow damaging the enamel of my teeth and making it more likely that I would have problems?

I worried about my tongue: what if it I wasn’t positioning it in the right spot? Could it be hit by one of her picking devices, causing me to bleed, which would then cause the multiple bacteria now swarming in my saliva to gain entry into my bloodstream, perhaps landing on a heart valve and causing an infection, endocarditis, that would then result in a need for valve replacement surgery?

Periodically she would squirt a liquid into my mouth and then ask me to close my lips around the plastic sucking device. How well had the sucking device and the squirting tool been cleaned before the last patient and how I could I possibly verify this? I had to put my complete trust in this dental hygienist who I had never met before. I didn’t know what her training was.  I didn’t know what her level of compulsiveness with regard to germ transmission was.

Did I want her to be very aggressive with the cleaning or superficial? Which was better? Previously, I have had both approaches and I’m usually thankful for the brief, superficial variety.

Donna announces that she will be “polishing” my teeth and the dreaded rotary brush, coated with nasty paste is applied. What are the component of the paste? Is it likely to fly off into my lungs and set up a nidus for an inflammatory nodule?  If I swallow it will its toxic contents be absorbed into my blood stream and destroy my liver?

At the very instant that she is done, the dentist enters the room and greets me with a hand shake; he is an affable, fifty-something fellow in  casual dress. I have revisited this dentist a second time because he didn’t find anything amiss the first time I visited him.

I have an intense distrust of dentists, as I have found their “cavity detection rates” differ wildly. (I went to the same dentist in Louisville for 5 straight years and he gave me rave reviews about my teeth.

My first visit to a different dentist (highly recommended by a mysophobic ex-wife), resulted in the identification of several (asymptomatic) cavities and subsequent fillings – the first cavities I had had in twenty years. I left her and went back to the guy who never found cavities. (Interestingly, one who studies cavities is termed a cardiologist).

Donna told me that I have some build up of tartar. I ask her to define it and she tells me tartar is plaque on the teeth that has become calcified. I ponder the similarities between the development of calcified plaque in the coronary arteries and the teeth. About ten years ago cardiologists felt there was a connection between ginigivitis and coronary atherosclerosis, possibly mediated by inflammation, but this has mostly been discredited.

I ask Dr. Watley what the significance of tartar and plaque is. He seems a little taken aback and launches into a description of what “some say:” bacteria build up in the plaques around the gums and launch themselves into the blood stream,  landing on heart arteries, pancreas, and spleen.  

At first I think he must have forgotten that I am a cardiologist, but then he asks me what I think of his theory;  I tell him there is little scientific support for it. He admits that his other cardiologist patient doesn’t believe it either.

I ask him what the value of a routine cleaning is.  He says “Donna, what do you think? Donna, clearly nervous, talks about preventing bacteria from building up.

I ask “Is there any evidence that annual cleaning is better than another interval?” He says that those who get cleaning every 4-6 months do much better than those who don’t. No doubt!!!

Dentists, like cardiologists, benefit financially from having exams done on a regular basis.  It’s hard to get unbiased information from your dentist or cardiologist, or an organization run by dentists or cardiologists, on the value of routine cleaning or cardiac testing or the frequency at which examinations or testing should be performed.

In Part II of this post, I’ll present the scientific evidence, if any, to answer some of the questions I’ve posed above.

Despite my distrust of dentists, I want to make it very clear that I am not a RABID anti-dentite.

-ACP

Part 2, can be found here