Brain tumors linked to dental X-rays
April 10th, 2012
12:01 AM ET

Brain tumors linked to dental X-rays

A study published this week in the journal Cancer shows that people who have had dental X-rays are more likely to develop a type of brain tumor called meningioma than those who have not.

This does not prove that dental X-rays cause tumors. But it supports previous research about the connection. Dental X-rays have also been implicated in thyroid cancer. But there's still significant doubt about the existence of any direct relationship between meningioma and dental X-rays, and dental professionals were quick to call for more research, saying the study was less than perfect.

"It’s a cautionary tale ... we do know that radiation can cause tumors, and we have to be judicious with its use," said Dr. Donald O’Rourke, an associate professor of neurosurgery at the University of Pennsylvania who was not involved in the study.

Meningiomas are the most frequently occurring tumor in the head. They are located in the meninges, the tissues covering the brain. The vast majority are "benign" - or noncancerous - but, depending on their location, could cause blindness or other serious neurological damage. Those in the skull base are more difficult to remove in their entirety. Depending on the tumor, surgery may not be required.

Dr. Elizabeth Brooks Claus, director of medical research at Yale University's School of Public Health, led the Cancer study, which focused on patients whose tumors required surgery. The patients were mostly Caucasian because of the regions from which they came; Claus' group plans a follow-up looking at more African Americans, who have a statistically increased risk for meningiomas.

The average age of the 1,433 patient participants was 57, which means their exposures to dental X-rays were likely of a higher radiation doses because of older technology, Claus said. But they ranged between 20 and 79 years old, and came from select parts of the United States. Researchers also looked at data from 1,350 people with similar characteristics who had never had a meningioma.

The meningioma patients had more than a two-fold increased likelihood of having ever experienced a dental X-ray test called a bitewing exam. Depending on the age at which the exams were done, those who'd had these exams on a yearly basis, or more often, were 1.4 to 1.9 times more likely to have had a meningioma.

Four of these X-rays is about the same amount of radiation you're exposed to in a typical day: .005 .millisieverts, according to the American College of Radiology.

Panorex exams, which involve images of all of the teeth on one film, were also linked to meningioma risks. If study participants had panorex exams when they were younger than 10 years old, their risk of meningioma went up 4.9 times. One of these around-the-head X-rays carries about twice as much radiation as four bitewing X-rays.

"My impression is that people get more dental X-rays more frequently than the American Dental Association says," Claus said.

For an adult without cavities and no increased risk for cavities, who is not new to his or her dentist, x-rays are recommended every two to three years. For a child without cavities who's not at increased risk, the interval is every one to two years, according to this chart from the Food and Drug Administration.

There's currently a low threshold for dentists to order dental X-rays, says Dr. Keith Black, director of the Maxine Dunitz Neurosurgical Institute at Cedars-Sinai Medical Center in Los Angeles, who was not involved in the study. Even if X-rays are not necessary for a procedure, dentists often request them as part an annual exam. Black hopes dentists will pay attention to this research linking the X-rays to brain tumors.

There are important uses for dental X-rays in making decisions regarding certain procedures. But if the teeth are otherwise healthy, Black recommends against the radiation.

There is a latency period - a lag time - of about 20 to 25 years with meningiomas induced by radiation, O'Rourke said. Only about 1% to 5% of meningiomas are cancerous, but in people with known increased radiation exposure, that risk can go up, he said.

But Dr. Otis Brawley, Chief Medical Officer of the American Cancer Society, which publishes the journal Cancer, points out that the study relied upon individuals' memories of how many dental X-rays they'd had, including in childhood, so there is room for error in that regard. And, again, it does not prove that X-rays directly cause tumors.

There are, however, estimates that up to 1% of all cancers in the United States are due to medical radiation, Brawley said.

In response to the study announcement, the American Dental Association also mentioned the study's reliance on individuals' memories.

"Studies have shown that the ability to recall information is often imperfect," said a written statement from the ADA. "Therefore, the results of studies that use this design can be unreliable ..."

The ADA also pointed out that the study included people who received dental x-rays decades ago from older technology that exposed them to more radiation. "The ADA encourages further research in the interest of patient safety," said the statement.

If you've already been getting annual dental X-rays, there's nothing you can do to mitigate whatever risk you already have. But Black said this research is important to keep in mind when making decisions in the future, and for children.

soundoff (532 Responses)
  1. priyanka

    Read this!!!

    April 10, 2012 at 06:57 | Report abuse | Reply
  2. SixDegrees

    There's a frustrating lack of information here, namely: what is the absolute rate of these cancers, both with and without x-ray exposure? A doubling of cancer rates certainly sounds like a bad thing, but if the baseline rate is 1 in 100,000, increasing my risk to 1 in 50,000 – for a cancer that is only malignant 1% of the time – doesn't seem like a bad trade off.

    But we get nothing. Shoddy reporting.

    April 10, 2012 at 06:58 | Report abuse | Reply
    • FactChecker

      @SixDegrees :"There's a frustrating lack of information here, namely: what is the absolute rate of these cancers," - The article is full of information and it does say "Meningiomas are the most frequently occurring tumor in the head". If you want to do specific calculations you will have to do your own literature search.

      April 10, 2012 at 07:52 | Report abuse |
    • JC

      Did you get up on the wrong side of the bed today? Shoddy reporting? I wouldn't go that far. Try http://www.ada.org for more info.

      April 10, 2012 at 08:03 | Report abuse |
    • inachu

      Getting cancer to inspect your teeth is a good tradeoff?
      Along with other x-rays while the x-ray technician sits behind the shielded room area with a lead vest and you are being nuked by x-rays. Sounds very healthy indeed!

      April 10, 2012 at 08:42 | Report abuse |
    • SixDegrees

      "Getting cancer to inspect your teeth is a good tradeoff?" – As noted, there's no way to make such a determination from the information provided in the article. The relative difference is high, but a rational determination on whether x-rays are worthwhile or not requires the absolute rate. If x-rays move the chances of such cancers from 1 n 100 to 1 in 50, I'd be considerably more reluctant to have one than if the change were from 1 in 100,000 to 1 in 50,000.

      April 10, 2012 at 09:24 | Report abuse |
    • SixDegrees

      "do your own literature search"

      "{insult} Look at {some website}"

      Like I said: shoddy reporting. It shouldn't be too much to ask of the reporter to provide such a simple fact, or to have them understand that the article provides little useful information without it. If I have to go dig up the information myself, what's the point of paying a reporter anything in the first place? Why not just have a list of headlines, with a link to Google below each one and no further text at all?

      April 10, 2012 at 09:34 | Report abuse |
    • pam

      Isn't cancer always malignant?

      April 10, 2012 at 09:36 | Report abuse |
    • Lois

      @Pam, Yes, cancer is always malignant, but not all tumors are cancer. The article says that not all meningiomas are cancerous but not very clearly. I can see how it can be confusing.

      April 10, 2012 at 10:10 | Report abuse |
    • JeramieH

      > the x-ray technician sits behind the shielded room area with a lead vest

      Because he's doing it 8 hours a day, 5 days a week. You're doing it once every few years.

      April 10, 2012 at 11:08 | Report abuse |
    • JC

      This report is about the findings of a study relating some types of brain tumors and dental x-rays. It's is not intended to be a end-all resource on radiation and cancer.

      April 10, 2012 at 23:15 | Report abuse |
  3. az

    So all this is bad but the naked body scanners by TSA are good for you?

    April 10, 2012 at 07:16 | Report abuse | Reply
    • tatatoothy

      Great point.

      April 10, 2012 at 07:32 | Report abuse |
    • FactChecker

      One thing that might ease your mind - the TSA scans are at a frequency designed not to penetrate flesh so things carried can be seen clearly without skeletons, etc. Dental X-rays penetrate flesh very easily.

      April 10, 2012 at 08:01 | Report abuse |
    • factcheckernumber2

      one thing that may not ease your mind. as mentioned above the scanners are designed to not penetrate flesh, however to get skin cancer it does not need to penetrate very far

      April 10, 2012 at 08:14 | Report abuse |
    • Thegoodman

      The TSA scanners are not FDA approved. There is no research being done to determine if they are even remotely bad for us. There are two types of scanners, one uses x-rays and one uses ultrasound. From what I have read recently, no research has been done on either.

      Opt out of the scans. I do.

      April 10, 2012 at 08:55 | Report abuse |
    • cpt obvious

      Not only are the TSA scanners bad for you, they've already been defeated. Search for bypassing body scanners to see how trivial that is. Way to go TSA!

      April 10, 2012 at 09:14 | Report abuse |
  4. The TRUTH

    So, I go back to what concerns me even more ... the overuse of cell phones, which are held up to the ear for hours a day over the course of years .... low level radiation for a LONG time. Let's see what trends begin to happen in 2015 +, twenty years after the masses really starting using cell phones.

    April 10, 2012 at 07:22 | Report abuse | Reply
    • Consultofactus

      There's radiation and then there's ionizing radiation. Planck's equation E=hf tell us that a photon of cell phone energy withits 2.50E9 frequency (actually most are even lower) does NOT have the energy required to break bonds in organic chemistries – not by a long shot. For a frame of reference, UV DOES have such energy, but its frequency is 1E16 or ten million times the energy of cell phone radiation per photon.

      April 10, 2012 at 07:56 | Report abuse |
    • OldIgnorantEuropean

      @Consultofactus – that's rubbish too, a bond does not need to be broken for a photon to have had an effect. That is so Bohr. If you are a physicist, you know that too. You cannot prove that a wave of vibration sent along the bonds of a complicated molecule – which is in interaction with complicated, surrounding molecules – has no functional effect, or that a standing waves along the double helix is impossible etc. Physics is great, but mind the hubris.

      April 10, 2012 at 13:06 | Report abuse |
    • Consultofactus

      @OldIgnorantEuropean "....molecules vibrate" Ummm yes, unless it is at absolute zero, molecules are in constant motion, vibrating, twisting you name it. You are confusing the mechanical stress of materials at macroscopic levels with the notion of an atomic bond. Big difference – an atomic bond doesn't "wear out" like an overused piece of string. Like other quantum phenomena, the bond either exists or it doesn't....there's no such thing as a weakened atomic bond.

      April 12, 2012 at 08:12 | Report abuse |
  5. OldIgnorantEuropean

    I am very surprised. Dental checkups with x-rays are very infrequent in my country. Although the equipment is very
    modern, they only make a photograph when there is an indication or uncertainty (as in changing the dentist, but even in that case, you usually bring along/they ask for the previous shoots). The dentist and his assistant duck away, one to two rooms further away, whenever they do an X-ray: they don't like it either. The whole idea of an annual x-ray is appalling. It must be an endemic rip off of the insurance companies by US dentists.

    April 10, 2012 at 07:31 | Report abuse | Reply
    • okiejoe

      The reason the x-ray tech steps away is that, while you may have one x-ray in a year, she may do a thousand or more in a year. That makes a big difference.

      April 10, 2012 at 08:55 | Report abuse |
    • Laura

      I agree. I lived in Germany for 10 years and had one x-ray. Here, every dentist I called said they would insist on shooting my children with radiation. So my children have not seen a dentist in 3 years. I feel the benefits of not catching a cavity in its infancy do NOT outweigh the risks of cancer.

      April 10, 2012 at 09:03 | Report abuse |
    • Corpus Christian

      It seems to me that having dental x-rays has become more common recently. I would love to know if patients without Dental Insurance have as many x-rays taken as those with Dental Insurance.

      April 10, 2012 at 10:13 | Report abuse |
    • JuneCleaversBeaver

      Lemme guess; Rotten European teeth are common in your country.....

      April 10, 2012 at 10:15 | Report abuse |
    • Mark

      Surprise, in the United States we provide modern medicine! I'm a dentist, and I make sure that my own kids, my mom, myself, friends, etc. get tooth x-rays every year. If it were some sort of money making conspiracy, I wouldn't expose my own kids. One small cavity contains trillions of colonizing bacteria releasing waste, hormones, and byproducts into your mouth and body. Periodontal disease is linked to heart disease, diabetes, pre-term birth, etc. X-rays are the only way to detect early decay that forms in between the teeth. This study is inherently flawed. With a hundred million people getting routine dental checkups in the US, why only do a study with 1400 people? Research bias. Don't listen to these fearmongers. Your oral health is worth protecting.

      April 10, 2012 at 10:30 | Report abuse |
    • OldIgnorantEuropean

      Do I fit your US-stereotype 'rotten European mouth'? No, one crown, a few dental composites, not a single new cavity in the last five years. But I also don't have the US-modeled hyper-white teeth that look exactly like dentures but are real teeth when you ask about it.

      April 10, 2012 at 11:26 | Report abuse |
  6. Peter

    My dentist has been trying to get me to go for XRays for the past 5 years. I told him that I will let him know when my teeth hurt.
    At the airport, I go through pat-downs.
    Cell-phone, use an ear piece with the phone remote.
    You have got to use common sense people.

    April 10, 2012 at 07:32 | Report abuse | Reply
    • Brian Davis

      "...Cell-phone, use an ear piece with the phone remote. You have got to use common sense people..."

      Thank you. The combination of those two sentences was the funniest thing in my morning. Keep working on the common sense 🙂

      April 10, 2012 at 08:51 | Report abuse |
    • Mark

      i'm laughing too. If you wait until it hurts it means that you have a cavity big enough to effect the nerve in the tooth, which probably means a root canal. Root canals usually require 6-10 x-rays, so you're getting your radiation exposure all at once rather than over time with a couple of x-rays per year.

      April 10, 2012 at 10:38 | Report abuse |
  7. tatatoothy

    I truly worry that we haven't learned enough yet about radiation's negative effects and that news like this will become more and more prevalent in years to come.

    April 10, 2012 at 07:33 | Report abuse | Reply
    • JeramieH

      X-rays were discovered in 1875. I think we've learned some about them in the past 137 years.

      April 10, 2012 at 11:13 | Report abuse |
  8. TM

    The study relies on the patients ability to remember bitewing X-rays? I wonder how many patients even know what a bitewing xray is.

    "Four of these X-rays is about the same amount of radiation you're exposed to in a typical day: .005 .millisieverts" – ACR


    take a look at that chart, something tells me that judicious use of the CT scan may be more at cause. Even if a person goes and gets these "dangerous" bitewing X-rays taken every 6 months from 13 years old to 80 that equals .67 mS, significantly less than just one CT scan.

    CNN has a responsibility to accurately report articles and be critical of bad research practices. Please use that to educate the public, not instill fear into them.

    April 10, 2012 at 07:42 | Report abuse | Reply
    • L C B

      Good input – thanx for adding some helpful calculation ... that makes some sense, for the general reader!

      April 10, 2012 at 08:02 | Report abuse |
    • JC

      No one remembers bitewing x-rays? Perhaps you don't visit a dentist or have refused x-rays for years, but they're still used today. What is inaccurate about the story? The report is about a correlation between dental x-rays and a specific type of tumor. It is not a comparative analysis between dental x-rays and other types of diagnostic x-ray exposure. OK, I'll buy that CT scans expose a person to more radiation than dental x-rays, but it would appear to me that the average person would have many more dental x-rays than CT scans. In fact, I've never had a CT scan.

      April 10, 2012 at 08:23 | Report abuse |
    • TM

      i didn't say that no one remembers bite wings. To say that someone remembers the number of bite wings received in their lifetime is ridiculous and to base a research paper off of that is even more so

      April 10, 2012 at 08:56 | Report abuse |
  9. Veteran's Son

    I was always sure that there was a link between dental xrays and brain cancer. My father and two of his best friends were dental technicians in WWII. Although they were otherwise quite healthy, they all died in their 60's with brain tumors. I always wondered how many others in their field suffered similar deaths.

    April 10, 2012 at 07:45 | Report abuse | Reply
    • JeramieH

      As dental technicians, were they constantly x-raying their own heads for some reason?

      April 10, 2012 at 11:14 | Report abuse |
  10. SM

    Chances are good that people that are anal retentive enough to get yearly dental X-rays are probably getting all sorts of other tests as well. Hypochondriacs get sick more often because they tend to hang out around places that have lots of sick people. A self-fulfilling prophecy.

    April 10, 2012 at 07:52 | Report abuse | Reply
    • Jim

      Do you really think that someone fortunate enough to have annual dental appointments, and who then follows the advice of his dentist to have a bitewing xray done, is anal-retentive and a hypochondriac? I hope you don't work in the medical field.

      April 10, 2012 at 08:28 | Report abuse |
    • Brian Davis

      Thanks. I had no idea that brain cancer was catching. I'll be more careful in hospitals in the future.

      April 10, 2012 at 08:53 | Report abuse |
  11. Carla

    When my daughter went to Six Day Dental, they gave her a panaromic x-ray becuase the regular x-ray machine was full. She was 7 years old. I had no idea that was a concern and no one told me.

    April 10, 2012 at 07:59 | Report abuse | Reply
  12. Hugh Jass

    Cheez, I've had a bunch of those over the years. More good news.

    April 10, 2012 at 08:03 | Report abuse | Reply
  13. BillRubin

    A flight from NY to LA has about 8x the amount of radiation from a dental x-ray. The amount of radiation from an airport scanner is equivalent to the radiation received from eating 1 to 25 bananas. But you rarely see articles about the radiation from flying or eating bananas.

    Source: http://www.informationisbeautiful.net/visualizations/radiation-dosage-chart/

    April 10, 2012 at 08:05 | Report abuse | Reply
    • Joshua Ludd

      Well, those types of radiation are also not directed fully at your head.

      April 10, 2012 at 10:55 | Report abuse |
    • BillRubin

      Yeah it's not just to your head, it's 8 times the radiation to your head and body. I think you're confused about energy measurements and distribution – your head is still getting 8x the radiation.

      April 10, 2012 at 11:44 | Report abuse |
  14. ppedo

    /the people who developed the tumors also watched TV and pumped their own gas. This is like saying that geese flying south in the fall cause winter! Totally irresponsibe journalism. (is that redundent?).

    April 10, 2012 at 08:05 | Report abuse | Reply
    • JC

      You are criticizing the study, which was conducted by Yale University. CNN is reporting on the study. That in itself is not irresponsible journalism.

      Sounds like you don't have any faith in the scientific method. Personally, I give the researchers a little more credit than you do. I admit I haven't read the details on this research beyond this report, but I believe the researchers do interview each patient to look for other common factors that could explain the tumors.

      April 10, 2012 at 08:38 | Report abuse |
    • RobC

      Most gas stations were full-service (attendants pumped the gas) until the '90s, and the older-style television sets used different technology.j If it comforts you to dispute this likely link between a common procedure and brain cancer, though, go for it.

      April 10, 2012 at 08:41 | Report abuse |
    • Darth Cheney

      You do not understand the logic of science. People who do NOT get x-rays also pump gas and watch TV, presumably at similar levels as everyone else. Yet, people who DO get x-rays get tumors at a higher rate. Thus, we do not attribute increased tumor rates to gas pumping and TV watching. You got that?

      April 10, 2012 at 10:16 | Report abuse |
  15. Saint_John

    I'll take my chances with the dental x-rays. Decaying teeth and infected gums can kill you, not to mention it makes one very unattractive, not tha there's anything wrong with that. Just say'n

    April 10, 2012 at 08:08 | Report abuse | Reply
  16. naro

    1433 patients studies is a tiny number for such a rare benign tumor. I think that the study can be discarded. So the risk in this unrepresentative group was 1.4 to 1.9 times non exposed (why such a wide range is not explained). So if you take their conclusion as true then instead of 1 in a million getting the tumor 2 in a million will get it. Not a big difference.
    Just another academician trying to do something with their time to show that they are busy.

    April 10, 2012 at 08:13 | Report abuse | Reply
  17. Quid Malmborg in Plano TX

    This explains why the British- the English in particular- have the lowest rates of brain cancer in the entire world.

    April 10, 2012 at 08:18 | Report abuse | Reply
  18. twang

    I recomend that all african americans get as many dental xrays as posible

    April 10, 2012 at 08:20 | Report abuse | Reply
  19. nros

    This article doesn't mention the use of digital x-rays that are now commonly used in a lot of dental offices. 4 bitewing X-rays in digital form is equal to 1 bitewing X-ray in the old-school film form. So the exposure to radiation is a lot less than before. Given that 4 regular film bitewing X-rays is equal to the amount of radiation you're exposed to on a regular day, I don't see what the big deal is getting a little extra dose every one to two years. I'd say tanning beds, CT scans, and sun bathing at the beach is more dangerous...

    April 10, 2012 at 08:22 | Report abuse | Reply
    • Jim

      The radiation from dental x-rays is concentrated in one area – your face/throat/brain, not disseminated throughout your body (which still isn't a good thing).

      April 10, 2012 at 08:38 | Report abuse |
  20. Juan Torres

    To all: get rid of your microwaves. To all "Google" this " dangers of eating microwaved foods".

    April 10, 2012 at 08:29 | Report abuse | Reply
  21. Faith

    What about TSA and the XRay's at the airport.... Everywhere we go there is XRays.... or Radiation. What about the new Smart Meters on our homes.... they shoot it into every plug in your home, all TV's and Computers as well.

    April 10, 2012 at 08:33 | Report abuse | Reply
    • Don

      You mean the electric meters? Those use radio waves. They aren't any more dangerous than . . . a radio.

      April 10, 2012 at 09:05 | Report abuse |
    • Hugh Jass

      ". they shoot it into every plug in your home, all TV's and Computers as well."
      X-rays? No. Electricity is not x-rays. None of the stuff you mentioned is x-rays. Radios and telephones are not x-rays. Even the airport scanners are backscatter scans, not direct x-rays.

      April 10, 2012 at 16:30 | Report abuse |
  22. BFranklin

    Where do you find people who haven't had dental X-rays?

    April 10, 2012 at 08:34 | Report abuse | Reply
    • Hugh Jass

      They are called "the poor." Amazingly, they don't have a lot of money. Let 'em eat cake though, eh?

      April 10, 2012 at 10:27 | Report abuse |
  23. Youth Advocate

    Every study has limitations and flaws. I am certain if you read the published journal article, the authors will highlight those limitations. This is one study of hundreds, most of which send the message that there may be a link between those x-rays dentists say are innocuous (and generate income from) and cancer. One bottom-line is that never should you agree to a procedure that has no direct benefit to prevention or treatment, such as yearly/bi-annual dental x-rays.

    April 10, 2012 at 08:38 | Report abuse | Reply
  24. mdbill

    i'll tell you why dentist do xrays at the drop of a hat, money – clear and simple. i see my child's cleaning bill go from $160 to nearly $300 as soon as the xrays start. i've argued with my wife until i'm blue in the face about the necessity of these xrays and the potential dangers, to no avail. maybe she will take notice now....

    April 10, 2012 at 08:44 | Report abuse | Reply
  25. Terry

    Frankly, I believe the research paper is weak at best. When interviewing the patients, the researchers were asking people to recall how many dental X-rays they had throughout their lifetime, which may be factual or not. What about cell phone use, or commercial airline flights taken, or tanning beds utilized prior to a special event, and the list goes on and on. Xray exposure has been reviewed for years and the trade offs can be an option going forward. However, the use of dental X-rays once or twice a year cannot be the sole cause of brain tumors.

    April 10, 2012 at 08:44 | Report abuse | Reply
  26. Anne

    Okay, so lots of more-or-less good information. The problem remains that medical studies result in statistical data, without demonstrating any cause and effect relationship. That is because every "body" reacts differently to stress ( radiation ), so some get tumors and some don't. Some "bodies" are somewhat radiation-resistant, others not so somewhat. And symptoms can develop over widely different time periods ( and arise from various "causes" ) so how can say what causes what? So how do we measure how much "our" bodies can take ( without killing us in the process ) ? The answer is we can't. Which means we each have to decide what risk we should take.

    This problem has been around for a very long time. During the early days of above-ground nuclear testing we routinely and deliberately exposed people to radiation to see what would happen. Some showed immediate symptoms. Some developed symptoms years later. Some never showed any symptoms ( and died of something apparently unrelated to radiation exposure ( but can we ever be sure ? ). So every "body" has a unique threshold and a unique body chemistry with regard to radiation exposure..

    Bottom line #1. Too much of anything can kill you ( the question is how much is too much ). Bottom line #2. Embrace a healthy lifestyle ( this reduces your chances of ill health, but may not prevent something more hereditary ).

    April 10, 2012 at 08:57 | Report abuse | Reply
  27. Lindalou

    There are so many man made hazards in this world, and unless we absolutely have to be exposed to any radiation it's a risk I don't want to take. Yes, I've heard the airplane comparison, but flying every couple of years puts me out of that danger. If that was the case wouldn't there be a high prevalence of cancer among pilots and flight attendants? Putting an x-ray millimeters away from my head and brain never sat well with me..I'll take my chances and turn them down every time. Dentists will have to make their money somewhere else with their bloated fees. How an hour in a chair equals a thousand dollars is beyond me.

    April 10, 2012 at 09:00 | Report abuse | Reply
  28. ann

    I wish they would quit reporting on studies that are clearly in the beginning stages as if they were totally proven. I know they give caveats to show that it isn't proven, but it gives the impression that they already know for sure that xrays cause brain tumors. Why not report on the studies that are further along and cover more individuals.

    April 10, 2012 at 09:00 | Report abuse | Reply
  29. Snaggle Toof

    This is precisely why I advocate complete exodontia and replacement with complete dentures. Based on this article I can save my brain!

    April 10, 2012 at 09:08 | Report abuse | Reply
  30. Jess

    I wonder if they thought to ask any of the participants in the study if they had braces as a kid. I had braces and had all kinds of x-rays done in the late 90's.

    April 10, 2012 at 09:09 | Report abuse | Reply
  31. Skeptic

    What do you know! Poverty could be a blessing in disguise. Not having money to see a dentist and therefore avoided the dental X-ray and therefore avoided meningiomas.

    April 10, 2012 at 09:17 | Report abuse | Reply
  32. Sam

    There's a "kickback" for the hygiensts if they can do xrays. For a regular patient there's absolutely no reason for them in your basic checkup. I found out that xrays do not even show if you've got a cracked tooth for example. That very very bright exam light can show many basic things that a dentist would need to know. As I look back over the years, my xrays have never, ever shown one problem!....and I'm in my 70s!

    April 10, 2012 at 09:21 | Report abuse | Reply
    • Honey Badger

      @ Sam.....How would a hygienist get a kick back if she's on an hourly wage? Did you develop a meningioma? If you didn't then maybe those radiographs prevented you from getting one huh? Same causal effect of the study logic don't you think? How many teeth did you have saved by those xrays and you not get a tumor? No matter. If you are 70 then it really doesn't matter if you have teeth or not. You don't need teeth in retirement homes where all you eat is tapioca. But don't give up hope...you could still develop a meningioma and have cause to blame us.

      April 11, 2012 at 01:17 | Report abuse |
  33. Peter

    I am a dentist and I can't believe that CNN would report on such a shoddy study. This study doesn't link dental x-rays and cancer. It provides a very tenuous correlation. This is a very big difference. COrrelation does not mean that the two are linked. Recall studies are also notoriously unreliable. No researcher worth their weight puts much stock in recall studies.

    It is stories like this that cause the public to fear dentists and what they do. I think Yale and CNN have done a great disservice to the public in perpetuating the idea that many people should avoid dental x-rays. We cannot treat what we cannot see. Cavities between the teeth can only be seen with x-rays unless they have already become very large – greatly increasing the risk of a root canal, crown, or extraction in the future. This is what bitewings allow us to see. Panoramic x-rays allow us to see the development of teeth, infections, and screen for cancer of the jaw. I would gladly trade the very small risk that dental x-rays pose for the ability to keep my teeth for the rest of my life.

    April 10, 2012 at 09:23 | Report abuse | Reply
    • Lois

      And Peter, am I right in understanding that the kinds of problems you mention frequently lead to gum disease? And isn't gum disease very highly correlated with increased cardiac risk? Something about similarities in the plaque? In any case, I'm all for making sure X-rays aren't overused, but I agree with you that this article is unnecessarily sensationalistic and fear-mongering. Recall studies are the least reliable. They said that the study participants were mostly Caucasians that needed surgery–the fact they could afford surgery suggests a higher level of income that would suggest the availability of regular dental checkups that would necessarily mean they have a greater chance of having any X-rays at all compared to a random samplying of the population, but that doesn't mean that radiation caused the tumors. Also, the study participants came from "select" parts of the U.S. Different parts of the country have different cancer rates due to natural and manmade reasons. Furthermore, to claim a true correlation between radiation from dental x-rays and these tumors, you would also have to adjust for vastly varying amounts of background radiation – residents of Denver receive twice the background dose as those at sea-level. People living and working in buildings with a lot of granite, those that travel by plane frequently, all of these people receive greater amounts of radiation exposure than the average person. If only I had time to go on on this topic...

      April 10, 2012 at 10:06 | Report abuse |
    • texas

      Thank you. I was looking for a response from a dentist & I'll be asking my dentist her opinion next time I go. As someone that has been going to the dentist & getting annual x-rays since the age of about 9 (yeah, we were poor and uninsured so I didn't go before then) & as someone diagnosed with a benign meningioma in my late twenties, I found the article interesting. I don't think we should jump to conclusions and stop dental x-rays, but this research simply suggest that it should be investigated in depth. This is a weird comparison, but it wasn't long ago that annual rabies shots were required for pets, but research showed that they could be given every 2 to 3 years and be just as effective. With the advances in dental care maybe annual x-rays aren't necessary, but complete research should be done to reach that conclusion.

      April 10, 2012 at 10:10 | Report abuse |
    • Sunshine

      I agree with your post. I work as a dental assistant and it is sad that people think we are asking for x-rays to run up a bill. Dentists are required to take x-rays to diagnose problems or potential problems. It also makes me upset when people don't see dentists as real doctors. These types of articles just make it worse for the profession and drive a wedge between patients and dentists. If you have concerns or questions ask your dentist, he is a licensed professional – not cnn or the public.

      April 10, 2012 at 10:17 | Report abuse |
    • Hugh Jass

      I have bad teeth and have lost them one by one until I have an upper plate. I'd rather have the teeth.

      April 10, 2012 at 16:32 | Report abuse |
  34. Joe

    When my young son goes to the dentist, I insist that they only use an x-ray if absolutely necessary.

    The dentist finally told me last time that she's going to drop him as a patient because it is her duty as a dentist to make sure his teeth are x-rayed every 6 months and that she can lose her license if she does not.

    April 10, 2012 at 09:27 | Report abuse | Reply
    • Montre

      Your dentist is flat out lying. She will NOT lose her license for not performing an xray. She will however lose a great deal of money from you.

      April 10, 2012 at 10:02 | Report abuse |
  35. Joe

    Further, as a nuclear engineer, I was surprised by the claims by the dentist's office that "We use a very, very small amount of radiation".

    Studies have shown that very small amounts of ionizing radiation can cause more damage than moderate amounts because when subjected to a moderate amount, the body recognizes it and responds... when it is a slight amount, the body doesn't respond. How could a dentist not be familiar with this concept?

    April 10, 2012 at 09:29 | Report abuse | Reply
    • Lois

      Joe, I was with you on the dentist wanting to X-ray your child every 6 months. She is lying if she says she would lose her license. But now, with the statement about "studies" on "very small" versus "moderate" amounts of radiation, I wonder if you're the one lying or delusional. If you really have a degree in nuclear engineering it's either been a very long time ago and your recollection from health physics lectures are faulty, or your school's accreditation should be yanked.

      April 10, 2012 at 09:46 | Report abuse |
    • Dan

      Can you name all the natural sources that emit very small amounts of ionizing radiation every day? We are constantly bombarded with very small amounts of "natural" radiation everywhere we go. Many of these new dental sensors are digital, requiring nothing near the radiation to what the conventional films required (which was small anyway). Goodness forbid we are non-SPF wearing, second-hand smokers living next to a mountain in Denver complaining about four bitewings every year. Look at the relative dosages.

      April 10, 2012 at 09:53 | Report abuse |
    • bellasue

      That is very interesting. I was never taught that in school but makes sense. The really never say much about exposure to radiation in schools. Mainly just taught to get a good view and read film.

      February 6, 2015 at 09:08 | Report abuse |
  36. pam

    Well hopefully this will slow down the ordering x-rays just to stick it to you when they aren't necessary.

    April 10, 2012 at 09:39 | Report abuse | Reply
    • bellasue

      I wouldn't count on it on their side but I would refuse

      February 6, 2015 at 09:10 | Report abuse |
  37. Robert

    Annual chest X-rays were discontinued years ago because of the dangerous and unnecessary radiation exposure. Why are dental x-rays the only diagnostic x-rays used regularly on healthy people? The answer is simple – all the dentists have these very expensive machines in their offices and have to pay for them by recommending annual x-rays! Why does every dentist need a machine? Most other doctors send their patients to an imaging center for these type procedures.

    April 10, 2012 at 09:44 | Report abuse | Reply
  38. Chacko Chakiath


    April 10, 2012 at 09:50 | Report abuse | Reply
  39. Saboth

    Now watch 40 years in the future: "X cancer rates are found to be higher in people that flew in the 2000s, due to government mandated scanning machines in airports."

    April 10, 2012 at 09:51 | Report abuse | Reply
  40. janie

    This kind of reporting is very unfortunate because it does not allow us as dental professionals to do our job. Bitewing xrays are designed to be diagnostic and catch cavities very early. Instead, people wait until they turn into something big like an abecess which is very dangerous and if left untreated could cause big problems other than needing a root canal which could have been prevented. Do your own research people. By the way, hygienist do not get a kickback, at least not in my office. If you are in an office like that, you were in the wrong office anyway.

    April 10, 2012 at 09:56 | Report abuse | Reply
  41. Jack H.

    Dental X-rays also cause reduction in your vision. Over 40 and If you dont wear reading glasses then after a few visits to Dentist you will need them, if you already do then you will have to get your glasses updated. There are mindless dentists that keep taking un-needed Xrays every time you visit.

    April 10, 2012 at 10:02 | Report abuse | Reply
    • Elisabeth King

      Sounds absurd to me....

      April 10, 2012 at 10:34 | Report abuse |
    • bellasue

      Oh they are not mindless. Their mind is on buying their kid that new car they are going to have to pay for

      February 6, 2015 at 09:11 | Report abuse |
  42. tooth

    what about digital radiographs were they included in the study which are about 60% less exposure

    April 10, 2012 at 10:03 | Report abuse | Reply
  43. Rob B

    Not having looked at the data, there could be some hidden correlation here. People who are more likely to have had dental x-rays tend to be wealthier people who have access to good medical care. Those same people are also more likely to: use cell phones, travel through body scanners at airports, and be around a lot of electronic equipment that could emit harmful radio waves.

    April 10, 2012 at 10:05 | Report abuse | Reply
    • Don

      Rob, could you expand a bit more on what electronic equipment emits "harmful radio waves" and in what way those radio waves are harmful? Some cited studies would be really nice to see.

      April 10, 2012 at 10:22 | Report abuse |
    • Vic

      Whatever the other person says, this the right way to think about it.

      April 10, 2012 at 11:16 | Report abuse |
  44. Janet

    Having had a large 4.5 cm. meningioma removed 7 years ago, this story interesting to me. Suffered for two years with blinding headaches, photophobia......left eye hemorrhages, saw 3 great opthalmologists, but nobody did a CT or MRI......then had both a day apart when headaches began waking me at night. My right leg had begun to drag when walking quickly, and handwriting changed significantly over 7 years. Could basrely sign my name. Good dental care is necessary.....so are bitewings......but I also had significant dental X-rays as a child for orthodontia......at a teaching center, SLU, and the dentist assigned to me was almost barbaric in his treatment of care, doing procedures over and over again in training, which my mother later confirmed were not the norm. So long ago, water under the bridge, so much more information now than then. Just glad my tumor was able to be safely removed and just had another clean MRI this week.

    April 10, 2012 at 10:10 | Report abuse | Reply
  45. prognosis

    We will see a dramatic increase in the number of cases of brain cancer in young adult's and men and women under 50"s in the future, as children who grew up with these procedures as norm will go through the stages of exposure more rapidly. This can be said about vaccines, cellphone waves, television affects on adhd... pretty much every negative, highly sensational, political controversial modern health diagnosis. And it is possible that these findings, even though some may say all the facts are never there in reporting, is in fact true. However, look over medicine over the course of our history. We have changed methods of various medical procedures and treatments so many times, if not more so in the past 30-40 years. So here is the question we should ask. How are such procedures put to bill and practice if it takes this long to undergo the research to understand the adverse effects? Is it all in the name of science? Should science then be contained until it is safe? Or is that an impossible feat, and as such is the sacrifices the present must make so the future can live on?

    April 10, 2012 at 10:21 | Report abuse | Reply
  46. rad666

    What is the energy level of Superman's x-ray vision?

    April 10, 2012 at 10:23 | Report abuse | Reply
  47. Cheetahe

    Not mentioned here that there are no rules on how much radiation the dental X-ray machines put out, and if they are no one is enforcing them.
    I had a dentist who had an old X-Ray machine, may be 40 years old, and when asked why he is not getting a new one he told me that the old one is still working. He was/is nuking his customers.
    Any increased cancer risk due a routine dental exam is not worth taking. We already are taking a tremendous amount of risk for a cancer due to our polluted environment and our food supplies.

    April 10, 2012 at 10:26 | Report abuse | Reply
    • TM

      there are laws stating that nuclear physicists need to come around every year to ensure that your machine is working up to standards.

      April 11, 2012 at 19:48 | Report abuse |
    • bellasue

      I worked for a dentist for years that had old machines. I now have a meningioma just discovered.

      February 6, 2015 at 09:16 | Report abuse |
  48. Elisabeth King

    A full set of dental xrays is the equivalent of 1 hour in the sun at the beach or a 4 hour flight across country. The amount of radiation is the same. This article is misleading and will only cause people to forgo xrays when clearly that is unneccesary.
    Your teeth are important and dental x-rays are needed to diagnose problems that your dentist cannot evaluate without them.
    My sister had a meningioma at age 17. It was benign and was removed in 1964 and she's 63 years old now and fine.

    April 10, 2012 at 10:30 | Report abuse | Reply
  49. John B

    I've been screaming at dentists for years about this. My son has had 8 dentists now because I REFUSE to allow them to do Xrays every 6 months to a year on him. He was diagnosed with a OPG (optic nerve glioma) 2 years after his first "panaramic" xray serious. Now...I never said that was the cause but when these damned doctors keep pushing the xrays in a perfectly health mouth they are just being greedy. I've had 4 doctors tell me that the LAW says they have to do Xrays. Stop irradiating your children people. Unless they need a quick bitewing there is really no reason for an xray ESPECIALLY in baby teeth.

    April 10, 2012 at 10:32 | Report abuse | Reply
    • OldIgnorantEuropean

      @JohnB A panoramic dental xray on a young kid? Without any serious medical indication? That is what you get in a society where everybody is taught to become a control freak and be proud about it. While the 'brain-tumor article' is an early report, at best, the insights that this thread gives me in US dentistry are highly fascinating. This thread is getting weirder than I thought already. [Note: must print and show to dentist.]

      April 10, 2012 at 13:25 | Report abuse |
    • bellasue

      You are so right. A kid does not need xrays. It is pretty easy to see a cavity by just looking on baby teeth. I bet you won't see them running their own babies through xray machines

      February 6, 2015 at 09:19 | Report abuse |
  50. Steve

    Trust me, between xrays, MRI's, CT Scans and dental xrays....you have more than likely already received more than the ADA's recommended levels of rad exposure. This was discussed just a few months ago, when the ADA was pondering if they should keep track, on your medical records, how many rads you had been exposed to, or how many tests you had that involved exposure to radiation due to the fact that Americans are getting zapped far more frequently than they have in the past.

    If the dr is looking inside you, you are being irradiated...and to be honest, other than the side effect of the dr getting a peek inside, you are getting cooked.

    April 10, 2012 at 10:46 | Report abuse | Reply
    • JeramieH

      > other than the side effect of the dr getting a peek inside

      Which is, after all, the whole point. That's like saying that staying alive is the side effect of breathing.

      April 10, 2012 at 17:46 | Report abuse |
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