I have this on my wall. No, really.

Two weeks ago the dental community was in an uproar. Morning news shows were making claims that “dental x-rays cause brain tumors” and “dental x-rays are linked to brain tumors.” What made dentists so mad? For one thing, dentists are an easy target. Many people have had bad experiences with dentists, many people are afraid of shots and a lot of folks associate toothaches with dentists. Dentists have baggage, and this news story didn’t help. So we’re kind of touchy.

There are a couple problems with the Yale research that these news stories were based on. First, the methods used in the study were questionable. But even if the results had been accurate, the news media took “x is related to y” to mean “x causes y.” This is a conclusion that the data do not support. There’s a lot more work that would need to be done before that conclusion would be fair. Just because red cars are twice as likely to be in accidents as blue cars, you cannot assume that the color of the car is what’s causing all the accidents!

Humans are kind of funny that way. Our brains love to “assign a cause.” We like to take two things that are proven to be related in some way and jump to a conclusion. Usually the conclusion we jump to is: “one thing is caused by another.” Dentists do it, too.

A recent statement from the American Heart Association has taken the dental world by storm over the last few days. Apparently the assumption that many dentists made about periodontal disease causing heart disease was firmly clarified by the AHA:

“The message sent out by some in health care professions that heart attack and stroke are directly linked to gum disease can distort the facts, alarm patients and perhaps shift the focus on prevention away from well-known risk factors for these diseases.”

Boom. That seems very clear to me. The statement continues:

“Although periodontal interventions result in a reduction in systemic inflammation and endothelial dysfunction in short-term studies, there is no evidence that they prevent ASVD [“atherosclerotic vascular disease” aka heart disease] or modify its outcomes.”

From what I can tell, the American Heart Association is saying “don’t use heart disease as a scare tactic about gum disease.” I think that’s fair. I’ve noticed for years that some dentists have played a little fast and loose with the relationship between gum disease and heart disease. The truth of the matter is that gum disease and heart disease share quite a few risk factors: smoking, age and diabetes to name a few. Gum disease is worth treating in its own right. Potential tooth loss, pain and bad breath are pretty compelling reasons to keep your gums healthy. It’s just that dentists were getting comfortable lumping potential systemic problems in with the other problems gum disease presents as a selling point to the treatment. This is intellectually lazy and we need to re-evaluate it.


The moral of the story is this: “is linked to” does not mean “is caused by.” Even when your brain really wants to take that leap, you need to take a step back and really look at the relationship between whatever variables are connected.

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If you’re looking for a dentist in Saginaw, we’re always happy to accept new patients! You can request an appointment online or call the office at (989) 799-9133. And, as always, you can email me at alan@meadfamilydental.com. I always answer my own emails!