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Tooth Cavities May Protect Against Cancer

Soulskill posted 1 year,3 days | from the take-that-dentists dept.

Medicine 149

Hugh Pickens DOT Com writes "John Gever reports at MedPage Today on a new study conducted by researchers from the University of Buffalo, which found that people with more cavities in their teeth are 32 percent less likely to suffer from head and neck cancers. 'To our knowledge, the present study suggests, for the first time, an independent association between dental caries and head and neck squamous cell carcinoma.' The researchers proposed a mechanism for the apparent protective effect: that cariogenic, lactic acid-producing bacteria prompt cell-mediated Th1 immune responses that suppress tumor formation. The team examined records of patients older than 21 seen in the university's dental and maxillofacial prosthetics department from 1999 to 2007, identifying 399 who were newly diagnosed with head and neck squamous cell carcinoma. Assuming that the association between caries and reduced cancer risk is real, the team suggests that one could regard the cariogenic bacteria as beneficial overall, with caries 'a form of collateral damage.' Therefore an appropriate strategy could be to target that effect specifically without aggressively targeting the bacteria. 'Antimicrobial treatment, vaccination, or gene therapy against cariogenic bacteria may lead to more harm than good in the long run.'"

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or brushing your teeth causes cancer (4, Insightful)

dominux (731134) | 1 year,3 days | (#44854793)

or people who fail to take care of their teeth happen to do something else beneficial. I don't see a cause -> effect mapping between these observations.

The bacterial excretions (4, Informative)

dutchwhizzman (817898) | 1 year,3 days | (#44854857)

The research suggests that the excretions of the bacteria and the bodies reaction to that are the cause -> effect mapping. However, your suggestion that toothpaste may have unknown carcinogenic properties could be just as valid.

Re:The bacterial excretions (0)

LesFerg (452838) | 1 year,3 days | (#44854997)

I recall an "alternative" medicine article I read recently (but didn't take too seriously) which insisted that raising the body's overall pH level above a certain point would pretty much give protection against cancer. This would seem to agree, if the acid excreted by these bacteria is the link, as suggested.
Hopefully these avenues are being investigated.

Re:The bacterial excretions (5, Informative)

Anonymous Coward | 1 year,3 days | (#44855117)

Raising PH level means less acidic. Acid excreted by these bacteria would decrease PH, not raising it.
PH less than 7 is acidic while PH greater than 7 is alkaline.

Re:The bacterial excretions (5, Funny)

Anonymous Coward | 1 year,3 days | (#44855955)

Let's not allow reality to get in the way of alternative medicine.

Re:The bacterial excretions (0)

hedwards (940851) | 1 year,3 days | (#44856959)

And your point is? Strong bases can burn tissue just as well as strong acids can.

It's alternative medicine so it's bunk, but dismissing it out of hand by drawing questionable conclusions makes you look just as foolish. It was the GP that said that these bacteria would raise the pH, not the article he was referring to.

Re:The bacterial excretions (4, Funny)

ColdWetDog (752185) | 1 year,3 days | (#44855763)

Sure, raising your body's pH to 12 (Clorox level [thecloroxcompany.com] ) would prevent cancer.

And a lot of other things.

Re:The bacterial excretions (2)

MightyYar (622222) | 1 year,3 days | (#44855495)

X-Rays??? LOL. Seriously, people who go to the dentist more often get more of 'em.

Re:The bacterial excretions (1)

mcgrew (92797) | 1 year,3 days | (#44855613)

I've wondered whether or not a dentist's drill could set you up for more cavities, does it perhaps cause microscopic cracks from the vibration?

At any rate I only see a dentist when a tooth hurts. I dislike having unnecessary ionizing radiation focused on my head, and dentists always want x-rays..

Re:The bacterial excretions (4, Informative)

lightknight (213164) | 1 year,3 days | (#44855897)

The X-Ray dose is trivial...especially the digital versions, which use, I believe, six times less radiation than a normal non-digital version.

http://www.physics.isu.edu/radinf/dental.htm

2 or 3 mrem is the reported dose for a dentist X-Ray.

http://www.nrc.gov/about-nrc/radiation/around-us/doses-daily-lives.html

On average, Americans receive a radiation dose of about 0.62 rem (620 millirem) each year.
   

Re: The bacterial excretions (1)

iamhassi (659463) | 1 year,3 days | (#44855741)

So then wouldn't it be the opposite? People with cavities had to have an x-ray to have those cavities filled, so more cavities = more xrays. Those without cavities just brushed their teeth frequently = no X-rays.

Re:The bacterial excretions (2)

gmuslera (3436) | 1 year,3 days | (#44856401)

Not just Triclosan [wikipedia.org] is present in several toothpastes [drbenkim.com] , but is also indiscriminate in what it kills. Not just kills the bacterias that cause the cavities, but all the others too, maybe including the ones that as a side effect, protect us from those cancers.

The trend of using antibacterial products indiscriminately is affecting the ecosystems that we have in us, in the gut, the mouth, and other places where having a bacterial ecosystem is something good for our health. Yes, could be bad boys down there, but killing most living animals because we don't like mosquitoes or tigers will affect us as part of that ecosystem in the middle/long run.

Another possible explaination (0)

Anonymous Coward | 1 year,3 days | (#44856703)

Floride is a carcinogen. Duh.

http://oehha.ca.gov/prop65/hazard_ident/pdf_zip/FLUORIDE070811.pdf

On the other hand, stop brushing your teeth and enjoy the heart attacks.

FRAUD ALERT! JAMA again. (2, Interesting)

Futurepower(R) (558542) | 1 year,3 days | (#44854965)

I agree. It could be the opposite, that whatever prevents cancer causes tooth decay. Or, that there is an accidental association caused by some effect not studied, like accidental, unknown bias in the selection of patients to study.

This seems to be intentional fraud by JAMA, the Journal of the American Medical Association. The abstract of the JAMA Otolaryngology -- Head and Neck Surgery article calls the effect an "association".

The abstract should carry a warning something like this: "This is just a discovery of an association. No claim is made that one effect causes the other."

Instead, "MedPage Today, LLC and the Perelman School of Medicine at the University of Pennsylvania" published the "association" as cause and effect: "Dental Caries May Protect Against Cancer". In my opinion, that is fraud of a kind that is engaged in again and again. JAMA knows this occurs and does nothing to stop it. Instead, the public is encouraged to believe that something far more important than an "association" has been discovered. In effect, JAMA is allowing dishonest advertising of the medical and dental professions. JAMA seems to be an aggressive organization that sometimes promotes financial success for doctors against the interests of the public.

Also, the PDF of the slides is misleading. My understanding is that fluoridation means monitoring the levels of fluoride and adding fluoride so that the amount in the water is sufficient, as a child's permanent teeth are growing, to prevent tooth decay over the child's entire young and adult life. Once fluoride is incorporated into the teeth of children, the problem of dental infection by decay-causing bacteria is solved, because the pH required to cause decay in teeth that have fluoride included is never achieved by the bacteria. So, the slides are talking about cures for problems that occur only in people who did not have fluoridated water in childhood. I have friends who say that fluoridation had that effect in themselves and their children.

Hugh Pickens (2)

Futurepower(R) (558542) | 1 year,3 days | (#44855053)

Another question: Does Hugh Pickens get paid for promoting this Slashdot article? Did someone at Slashdot get paid for including it?

Re:Hugh Pickens (-1, Offtopic)

mcgrew (92797) | 1 year,3 days | (#44855627)

Another question: Does Hugh Pickens get paid for promoting this Slashdot article?

Are you getting paid to make offtopic comments? Nobody made you click the link. If you don't want to read it, don't read it.

Re:Hugh Pickens (1)

jones_supa (887896) | 1 year,3 days | (#44856089)

His questions were not offtopic.

Whoa, slow down there! (5, Informative)

mark_reh (2015546) | 1 year,3 days | (#44855497)

"Once fluoride is incorporated into the teeth of children, the problem of dental infection by decay-causing bacteria is solved, because the pH required to cause decay in teeth that have fluoride included is never achieved by the bacteria."

It doesn't work that way. I am a dentist and can guarantee you that even fluoride treated teeth and teeth with systemic fluoride incorporation can and do get cavities. I drill and fill them all day every day. Fluoride is only one factor in keeping teeth healthy. You still have to brush, floss, maintain a healthy diet, etc.

You changed the subject. (0)

Futurepower(R) (558542) | 1 year,3 days | (#44856821)

I feel uncomfortable with what you said, "I am a dentist and can guarantee you that even fluoride treated teeth...", because you jumped away from the subject, which was people who had fluoride during their entire childhoods, not "fluoride treated teeth". My understanding is that people who have had fluoride applied externally get some benefits, but not the complete benefits, which are far greater.

If you felt a need to change the subject, maybe you know what you said is not reliable. For example, as a dentist, you have no way of knowing the history of a patient when the patient was a child, unless the parent tells you.

So, for example, maybe a child lived in an area with fluoridated water, but drank sodas, or fruit juice made with fruit from another area with no fluoride in the water.

My information comes from people who have not had trouble with their teeth, and who lived with fluoridated water. They were all from well-educated families, so they did not do things that would, to an educated person, seem obviously self-defeating.

Re:You changed the subject. (1)

mark_reh (2015546) | 1 year,3 days | (#44857229)

I don't understand. Are you a dentist? And what does changing the subject line have to do with the reliability of what I am saying?

I am confused.

Re:FRAUD ALERT! JAMA again. (1)

Anonymous Coward | 1 year,3 days | (#44855891)

Except this is a medical journal (by one of the big four publishers) with a specific target audience of medical doctors.

"Association" has a specific definition, doctors know this definition and would never confuse this article as stating a direct causal relationship. This definition is used throughout the medical literature (not just JAMA). From the journal's abstract (http://archotol.jamanetwork.com/article.aspx?articleid=1736930) they are merely reporting an unusual association.

If you go and read literature of a specialist field, that is great. But don't complain when you misunderstand the specific vocublarly of that specialty. You are obviously advocating for scientific journals to dumb down the language (impairing the readability), instead of using a concise word with a specific definition. Should we do the same for Physics journals or even Computer Science/Engineering journals?

You missed the point. (1)

Futurepower(R) (558542) | 1 year,3 days | (#44856711)

You completely missed the point. JAMA publishes scientific articles which are mis-reported in articles for average readers. JAMA does not try to stop the sensationalism.

Re:FRAUD ALERT! JAMA again. (2, Informative)

Anonymous Coward | 1 year,3 days | (#44856037)

JAMA is a publication by healthcare professionals, for healthcare professionals. Not for the public. In fact, very little of what is published in the medical literature can be interpreted without a broad understanding of physiology, pathophysiology, research design, and biostatistics. Your points against JAMA Otolaryngology are all based off of fundamental misunderstandings due to deficiencies in those areas. Let me address them not in the order you've brought them up, but from the "bottom up" so we can build off of prior knowledge.

First off, study design. Many of your points concern deficiencies in the abstract. The abstract's function is to allow a physician to gauge interest in the article's contents without having to read the entire thing. They're written under a strict word limit and are often submitted to the journal before the final draft of the article is completed, rendering many of them inaccurate. Additionally, the journal does not need to state that this is "just a discovery of an association". This is self-evident by the study design, which is identified in the abstract as "case control". This means that it is a retrospective study, and, by definition, cannot prove causality.

Moving onto the slides, I cannot find a download link, so I cannot verify that they are correct. I can, however, verify that your understanding of dentistry is incomplete. Fluoridation is the process of converting the outer layer of your tooth enamel from a weaker, non-fluoridated form to a stronger form which incorporates fluoride ions. This change renders the outer layer of your teeth more resistant to (but not immune to) scratching, chipping, and dissolution at low pH (such as is produced by oral bacteria). Fluoridation is not a permanent process; like nearly all biological reactions, it is reversible, given time and liquid with which to dissolve extra fluoride ions. Your saliva is perfect for this. As such, humans need constant dental fluoridation. Fluoridated water goes a long way to providing this, but the process is easily overwhelmed by poor dental hygiene.

In addition, the "news article" against which you rail is another publication by and for doctors. Specifically, the article is intended as "Continuing Medical Education" (although I strongly doubt that it's accredited as such). Nowhere in the article is the discovery presented as causation. Nowhere in the article is a distinction between "link" or "association" or "correlation" and "causation" even necessary, given its target audience. In my opinion, the article provides a very brief and thorough overview of the article that helpfully highlights some of its major flaws--that it's single-center, retrospective, and was unable to control for confounding variables.

What your post does highlight is a huge issue regarding health information. In that there is quite a lot of it, and, despite being written in an approximation of normal English, many terms have connotations that lay people will not have the training to understand. When you add in a number of "health news reporters" without any medical background who write articles that are either materially false or easily misconstrued, you have a recipe for a system that the public does not trust. As of right now, there is a relative paucity of trustworthy health news for the general public. I urge you instead to speak with a doctor or pharmacist about the latest and greatest news so that you get the context required for interpreting the information.

Are you intentionally dishonest? (0)

Futurepower(R) (558542) | 1 year,3 days | (#44857165)

JAMA is a publication by healthcare professionals, for healthcare professionals. Not for the public. In fact, very little of what is published in the medical literature can be interpreted without a broad understanding of physiology, pathophysiology, research design, and biostatistics. Your points against JAMA Otolaryngology are all based off of fundamental misunderstandings due to deficiencies in those areas. Let me address them not in the order you've brought them up, but from the "bottom up" so we can build off of prior knowledge. First off, study design. Many of your points concern deficiencies in the abstract. The abstract's function is to allow a physician to gauge interest in the article's contents without having to read the entire thing. They're written under a strict word limit and are often submitted to the journal before the final draft of the article is completed, rendering many of them inaccurate. Additionally, the journal does not need to state that this is "just a discovery of an association". This is self-evident by the study design, which is identified in the abstract as "case control". This means that it is a retrospective study, and, by definition, cannot prove causality.

You completely missed the point, as I said above. JAMA publishes scientific articles which are mis-reported in articles for average readers. JAMA does not try to stop the sensationalism and dishonesty in the reporting for the public. There is a financial interest for doctors in being presented as knowing far more than they do.

Moving onto the slides, I cannot find a download link, so I cannot verify that they are correct.

The link to the PDF file is at the bottom of the Slashdot story: Antimicrobial treatment, vaccination, or gene therapy against cariogenic bacteria [ada.org] .

I notice that you don't say if they are correct.

Fluoridation is the process of converting the outer layer of your tooth enamel from a weaker, non-fluoridated form to a stronger form which incorporates fluoride ions. This change renders the outer layer of your teeth...

For some reason you have changed the subject to externally applied fluoride. I clearly said I was talking about fluoride internally ingested during the growth of a child's teeth, so that all the teeth have fluoride incorporated into the entire structure of the tooth, not just the outer layer, as you say.

Nowhere in the article is the discovery presented as causation.

Amazing that you say that! The discovery is presented a possible causation in the title: "Dental Caries May Protect Against Cancer".

What your post does highlight is a huge issue regarding health information. In that there is quite a lot of it, and, despite being written in an approximation of normal English, many terms have connotations that lay people will not have the training to understand. When you add in a number of "health news reporters" without any medical background who write articles that are either materially false or easily misconstrued, you have a recipe for a system that the public does not trust. As of right now, there is a relative paucity of trustworthy health news for the general public.

Again, you have jumped away from the subject. The subject is that JAMA knows the problem of exaggeration and dishonesty in medical reporting exists, but does nothing to stop it.

Fluoridation is the process of converting the outer layer of your tooth enamel from a weaker, non-fluoridated form to a stronger form which incorporates fluoride ions. This change renders the outer layer of your teeth more resistant to (but not immune to) scratching, chipping, and dissolution at low pH (such as is produced by oral bacteria). Fluoridation is not a permanent process; like nearly all biological reactions, it is reversible, given time and liquid with which to dissolve extra fluoride ions. Your saliva is perfect for this. As such, humans need constant dental fluoridation. Fluoridated water goes a long way to providing this, but the process is easily overwhelmed by poor dental hygiene.

Your are obviously a very sophisticated writer who knows a lot of science. So, I am guessing, and it is just a guess, that you are intentionally being dishonest. What you just called "Fluoridation" is topical fluoridation, not the complete incorporation of fluoride into teeth that occurs in children who have drunk fluoridated water during their entire childhoods.

Your saliva is perfect for this. ["dissolve extra fluoride"]

Saliva does not dissolve teeth enamel during the entire life of an adult. Saliva does not dissolve the stronger fluoridated teeth structure, either, of course.

By far the biggest problem with fluoridation of drinking water seems to be that it causes dentists to make less money, so they oppose it. When paint rollers were first introduced in the 1950s or late 1940s, professional house painters opposed them, because rollers encouraged people to do their own painting.

I urge you instead to speak with a doctor or pharmacist about the latest and greatest news so that you get the context required for interpreting the information.

That is my entire point, corrupted entirely! Medical professionals should allow the public to become educated. Instead, you are suggesting the public should remain ignorant, and be entirely dependent on professionals.

Re:or brushing your teeth causes cancer (3, Funny)

Shavano (2541114) | 1 year,3 days | (#44855043)

Flouride in our water is contaminating our precious bodily fluids.

Re:or brushing your teeth causes cancer (1)

Mystakaphoros (2664209) | 1 year,3 days | (#44855407)

Flouride in our water is contaminating our precious bodily fluids.

Mandrake? Can you hear me Mandrake?

Re:or brushing your teeth causes cancer (1)

MightyYar (622222) | 1 year,3 days | (#44855517)

I can assure you it has not recurred, Mandrake. Women uh... women sense my power and they seek the life essence. I, uh... I do not avoid women, Mandrake. But I... I do deny them my essence.

Re:or brushing your teeth causes cancer (-1)

Anonymous Coward | 1 year,3 days | (#44855131)

And vaccinating your kids causes autism.
Yeah, no thanks. I'll just keep brushing my teeth just in case.

Re:or brushing your teeth causes cancer (1)

DragonTHC (208439) | 1 year,3 days | (#44855557)

or perhaps sodium fluoride is carcinogenic.

Re:or brushing your teeth causes cancer (1)

Guppy (12314) | 1 year,3 days | (#44855793)

or people who fail to take care of their teeth happen to do something else beneficial.

Here's another possibility beyond what people have already mentioned -- People with bad teeth may have less oral sex. No, I'm serious:
http://www.hopkinsmedicine.org/kimmel_cancer_center/centers/head_neck/HPV_and_head_and_neck_cancer/hpv.html [hopkinsmedicine.org]

Re:or brushing your teeth causes cancer (0)

Anonymous Coward | 1 year,3 days | (#44855943)

No. It is because people who eat more sugar, get more cavities and it is the sugar that stops cancer. Thank you, I will accept the Nobel Prize in Medicine now.

Re:or brushing your teeth causes cancer (0)

Anonymous Coward | 1 year,3 days | (#44856243)

Or perhaps if a virus causes the cancer, the virus is also killing the bacteria that causes the cavities.

Re:or brushing your teeth causes cancer (1)

xtronics (259660) | 1 year,3 days | (#44856427)

Correlation does not show causation - did these so called 'science reporters' ever learn the scientific method?

It could be that people that get cancer are more prone to cavities - or both are induced by a third factor or just another random correlation.

Idiots are always reporting 'associations' and 'correlations' as if it proves cause and effect..

Re:or brushing your teeth causes cancer (1)

rsilvergun (571051) | 1 year,3 days | (#44856701)

I recommend reading up on the Scientific Body of literature put forth by Gen. Jack D Ripper.

Re:or brushing your teeth causes cancer (0)

Anonymous Coward | 1 year,3 days | (#44856851)

Maybe people with rotting teeth do not have as much oral sex.

Re:or brushing your teeth causes cancer (2)

hedwards (940851) | 1 year,3 days | (#44856939)

They may be onto something with this.

But it's also worth realizing that people with cavities are also more likely to have a dentist spending a prolonged period of time examining their mouths. And probably more time during each visit. Consequently having the dentist notice something on the x-rays that hasn't yet gotten to the point of being cancerous. I know I've had a biopsy done just to make sure that it was just a benign cyst.

I also wonder what the data looks like if you normalize it for people that have cavities because they take poor care of their teeth and individuals that just go long periods of time between seeing the dentists. It would be interesting to know if there's a difference in the rates.

Re:or brushing your teeth causes cancer (0)

Anonymous Coward | 1 year,3 days | (#44857233)

Could be something like the immune response to stress caused by cavities also happens to kill any cancer cells before they multiply into a bigger problem. I'd be willing to bet that a person with cavities is going to have a more robust immune system than those without.

Correlation != causation (0)

Anonymous Coward | 1 year,3 days | (#44854795)

Did anyone check the number / type of fillings used on the people with no cavities?

Re:Correlation != causation (0)

Anonymous Coward | 1 year,3 days | (#44855089)

Of course, "fillings" are irrelevant. It is "obviously" the bacteria causing the cavities ;-)

Welcome to "science"!

Alternative explanation of results (0)

Anonymous Coward | 1 year,3 days | (#44854801)

The reduction in head and neck cancers could instead be due to the fact that people with many cavities are likely to brush their teeth less often, and hence have less contact with (unknown) carcinogens in toothpaste.

xrays (1, Insightful)

Anonymous Coward | 1 year,3 days | (#44854803)

haven't read TFA, but could also mean those who get their carries fixed have more bitewing x-rays, which increases radiation to the head.

Re:xrays (1)

Shavano (2541114) | 1 year,3 days | (#44855057)

haven't read TFA, but could also mean those who get their carries fixed have more bitewing x-rays, which increases radiation to the head.

Because radiation prevents cancer???

Re:xrays (2)

Guppy (12314) | 1 year,3 days | (#44855559)

haven't read TFA, but could also mean those who get their carries fixed have more bitewing x-rays, which increases radiation to the head.

Because radiation prevents cancer???

He's saying that people who go to the dentist regularly (to get some cavities fixed) get fewer cavities overall thanks to better care, but they also get more dental X-rays. The amount of radiation in a dental X-ray is super-small and generally not considered a cancer risk; however, there's been growing use of Dental CT scans, which actually require a substantial dose to obtain.

Re:xrays (1)

kencurry (471519) | 1 year,3 days | (#44855739)

I think the hypothesis works better the other way: people who have fewer cavities because of regular dental checkups & regular x-rays, and are more prone to cancer in the head. Conversely, people who have more cavities are not taking care of their teeth, so less dental check-ups & x-rays.

Re:xrays (2)

MightyYar (622222) | 1 year,3 days | (#44855565)

Yes, they would need to account for extra dental care. It's also possible that people with fewer cavities see the dentist MORE often - that is, they take care of their teeth. This would make them more likely to floss, get regular cleanings, have tartar removed, get exposure to fluoride and toothpaste, and have regular x-rays. I'd bet this is an older population getting the cancers, so really we might be controlling for things they were exposed to years ago.

According to this research... (0)

Anonymous Coward | 1 year,3 days | (#44854807)

The British ought to have the lowest rates of head and neck cancers in the world...

Re:According to this research... (0)

Anonymous Coward | 1 year,3 days | (#44854989)

The blighties make up for it with ass cancer from all the bummings.

Re:According to this research... (1)

Anonymous Coward | 1 year,3 days | (#44855011)

Uh-oh. An Australian was awake.

Re:According to this research... (0)

Anonymous Coward | 1 year,3 days | (#44855141)

The blighties make up for it with ass cancer from all the bummings.

Not if they have their heads up their asses. Then it's a wash.

Fluoride (1)

return 42 (459012) | 1 year,3 days | (#44854845)

It seems that they did not control for exposure to fluoridated water. The article says "they had no data on the causes of missing teeth." It would be interesting to see if any clear results emerged from a study that did control for that.

However, given the level of entrenched interest in water fluoridation, I suspect it would be difficult to find funding for such a study, at least in the US.

Re:Fluoride (1)

AK Marc (707885) | 1 year,3 days | (#44854903)

"previous work examining periodontitis, which found that infections below the gum line are associated with increased cancer risk."

Gum disease causes cancer, cavities prevent cancer. I've not seen anything on fluoridated water in relation to the two, but it should address teeth only, and not the gums, so far as the tooth decay doesn't aggravate gum issues.

Re:Fluoride (2)

MightyYar (622222) | 1 year,3 days | (#44855581)

IINAD, but I seem to recall a study showing the tradeoff between people with acidic mouths and people with more basic mouths. The acidic mouths are more amenable to tooth decay, but less susceptible to tartar buildup and gum disease. The basic mouths tend to get fewer cavities, but they get more tartar and are more likely to see gum disease. Gum disease is inflammation, and inflammation gets tied to cancer.

On the other hand, they controlled for very little in this study, it would seem. Fluoride, x-rays, frequency of dental visits, etc.

effect of toothpaste? (0)

Anonymous Coward | 1 year,3 days | (#44854851)

Maybe time to study the effect of toothpaste and/or mouthwash on these afflictions.

The Fiendish Fluoridators (0)

Anonymous Coward | 1 year,3 days | (#44854915)

Florine causes cancer.

One page of Results and Methods (-1)

Anonymous Coward | 1 year,3 days | (#44854917)

3 pages of opinions...

There really isn't anything to say about this type research anymore except NHST is totally flawed and the results of studies analyzed this way mean nothing and contribute zero to negative value in terms of cumulative knowledge. In the future when actual medical scientists create models that predict things they will ignore this research because it provides no useful information such as the distribution of outcomes for each group. Mean and standard deviation means nothing for external validity in medical research.

I mean they couldn't even be bothered to make a bargraph to allow easy comparison of the results..

Re:One page of Results and Methods (1)

Joining Yet Again (2992179) | 1 year,3 days | (#44855021)

I read this article on some self-absorbed 'reason' site (any time a site explicitly describes itself with words like "reason"/"logic/"truth", you can take them as seriously as a site which uses phrases like "the way""the path"/"the light") about how common hypothesis testing is ALL WRONGGGGGGGGGGGGGGGGGGGGGG - never mind how in practice it confirms well enough the intended outcome.

FTFY.

Re:One page of Results and Methods (0)

Anonymous Coward | 1 year,3 days | (#44855029)

Yea, two groups are different somehow. That is all NHST will ever tell you and it will always be true. It is a tool of pseudoscience.

Re:One page of Results and Methods (1)

Anonymous Coward | 1 year,3 days | (#44855171)

Ronald Fisher, Jerzy Neyman, Karl Pearson, William Gosset, Egon Pearson, Paul Meehl, Jerome Cornfield, Alvan Fienstein

Short list (in rough chronological order) of big names who have expressed problems with NHST. And that ignores the Bayesian debate completely. Characterizing the issue as coming from blogs or whatever is completely disingenuous.

hmm (2)

Kaenneth (82978) | 1 year,3 days | (#44854939)

... Or is a common ingredient in toothpaste a carcinogen?

Re:hmm (0)

Anonymous Coward | 1 year,3 days | (#44855111)

THIS!

Re:hmm (1)

transporter_ii (986545) | 1 year,3 days | (#44855589)

Maybe they don't get cancer because they die of heart disease first: Tooth decay can cause heart problems

http://www.abs-cbnnews.com/lifestyle/11/25/10/tooth-decay-can-cause-heart-problems [abs-cbnnews.com]

MANILA, Philippines - Far as your pearly whites may be from your heart, dental experts say a small dental problem can go a long way. In fact, keeping your teeth healthy may just save your life.

-=-=

You know what else protects against cancer? Alzeimer's disease. People who get cancer rarely get Alzeimer's, and people who get Alzeimer's rarely if ever get cancer. see: http://www.nlm.nih.gov/medlineplus/news/fullstory_138596.html [nih.gov]

..but have a positive correlation w/ heart disease (0)

Anonymous Coward | 1 year,3 days | (#44854941)

Sorry can't find any good references right now, but here's this for starters:

http://www.webmd.com/heart-disease/features/periodontal-disease-heart-health

Fine, take them at their word. (1)

tlambert (566799) | 1 year,3 days | (#44854953)

Fine, take them at their word.

(1) Use the targeted approach to get rid of the bacteria.

(2) Immunize to provoke the Th1 response that prevents the cancer.

Leave it to a DDS to do a study saying "cavities are good, and we should not take any rash actions which would reduce the customer base for dentists, and if you do, you are all going to get cancer and die".

Re:Fine, take them at their word. (1)

Joining Yet Again (2992179) | 1 year,3 days | (#44854993)

Are there any good dentists in the UK? I used to think it was some antiquated stereotype that British people have poor dental health, but I've honestly never found a good dentist in the UK. And some of my dullest schoolchums went on to be dentists, eradicating confidence I might otherwise have in the profession's standards.

Re:Fine, take them at their word. (1)

mrbester (200927) | 1 year,3 days | (#44855137)

If you pay for it, most definitely. It has been my experience that NHS dentists aren't nearly as good.

Re:Fine, take them at their word. (1)

Joining Yet Again (2992179) | 1 year,3 days | (#44855239)

I've seen a private dentist nearly every time. And NHS dentists are just private businesses with an NHS contract, where the payments are shared between you and the government. Recent changes to payment structure have encouraged dentists to do slapdash NHS work, but even that's a symptom of the profession - contrast my GP, who already appreciates that he's well-paid, and actually spends his time maximising his productivity rather than squeezing out every last penny.

Re:Fine, take them at their word. (2)

mark_reh (2015546) | 1 year,3 days | (#44855515)

Ah! The old conspiracy theory of dentistry!

I can assure you, there is plenty of work for dentists without anyone having to try to promote cariogenic behavior. In fact, it is usually dentists who promote fluoridation of water as a preventive measure.

Oh wait, I know, fluoridation of water is some sort of conspiracy too...

Correlation due to lifestyle or diet? (2)

m00sh (2538182) | 1 year,3 days | (#44854967)

On Wikipedia, it's written that head and neck cancer

is strongly associated with certain environmental and lifestyle risk factors

The article says,

Other limitations included lack of data on potential confounders such as patients' diet and socioeconomic status

Isn't the work conditions one of the biggest things you look at in a cancer study? In the case of dental study, also diet.

Among 399 patients with head and neck cancer, current or previous dental caries were significantly less common than in 221 individuals without a cancer diagnosis,

Something like smoking or chewing tobacco would increase cancer risks but lower cavities.

Re:Correlation due to lifestyle or diet? (1)

DarkTempes (822722) | 1 year,3 days | (#44855221)

Or perhaps people who tend to get more cavities don't live as long (maybe even only for socioeconomic reasons) and thus are less likely to develop cancer?

I have no reason to believe that's true one way or another, it's just another potential idea.

Re:Correlation due to lifestyle or diet? (1)

umghhh (965931) | 1 year,3 days | (#44855353)

It actually may be the case. This type of cancer is not very common and is strongly correlated with risk factors like tobaco, alco etc use, but also exposure to some ugly things like HPV etc.

Re:Correlation due to lifestyle or diet? (4, Interesting)

Rockoon (1252108) | 1 year,3 days | (#44855231)

The problem with cancer studies is that so many disagree with each other, and there are so many studies that nobody in the field has a good grasp of things in general. Because of this, there isnt even a theory of cancer yet.

The U.S. National Cancer Institutes has resorted to hiring physicists such as Paul Davies [youtube.com] to try to get a better grasp of cancer, because the medical folk just arent getting anywhere. The video is in fact of Paul Davies giving a talk about the state of cancer research.

Re:Correlation due to lifestyle or diet? (1)

MightyYar (622222) | 1 year,3 days | (#44855681)

If I can't read TFA, do you think I can watch an hour-and-a-half video???

LOL, thanks for the link. It will make a nice podcast :)

Re:Correlation due to lifestyle or diet? (1)

Nate T (2879435) | 1 year,3 days | (#44856173)

I like his analogy of American colonization as cancer.

Preventing electrocutions by blowing up utilities (2)

K. S. Kyosuke (729550) | 1 year,3 days | (#44854981)

Even if this mechanism is real, cariogenic bacteria can only be beneficial if you're certain that tooth decay and the associated problems (abscesses, sepsis, etc.) won't kill you off before you get a chance to get cancer in the first place. It's all fine if you have access to a reasonably good dentist, like a third of the world or so in the past century, but otherwise...just ask Ramesses II.

Cool a win for a change (2)

Kuruk (631552) | 1 year,3 days | (#44854987)

Screw you colgate ! I win.

Ms Marsh, suck eggs :) (they prolly cause cancer)

Correlation != Causation (0)

Anonymous Coward | 1 year,3 days | (#44855073)

So on what basis do they conclude anything?

Honest investigation should investigate wether the "association" can have:
1) biological explanations (bacteria, viruses) associated with cavities.
2) dental hygiene explanations (dentist operations, toothpaste, mouthwash, wounds)
3) Hereditary explanations
4) Etc. I'm no expert, but I'm constantly irritated by poor reporting and poor scientific journals assuming too much.

This is what hinders progress: http://amasci.com/pathsk2.txt [amasci.com]

Re:Correlation != Causation (1)

K. S. Kyosuke (729550) | 1 year,3 days | (#44855093)

This is what hinders progress: http://amasci.com/pathsk2.txt [amasci.com] [amasci.com]

If the text you've linked is what hinders progress, why are you spreading links to it?

Feynman and brushing (0)

Anonymous Coward | 1 year,3 days | (#44855083)

http://m.youtube.com/watch?v=PsgBtOVzHKI&desktop_uri=/watch?v=PsgBtOVzHKI

Feynman was right making fun of tooth brushing ...

Maybe... (0)

Anonymous Coward | 1 year,3 days | (#44855125)

The body knows those cavites are there. Wants those germs dead just so bad. But. Can't really reach them or do much about it directly.
Oh but it can amp up the immune system patrols in the closest areas. Head and neck.
Just waiting for the bad guys to crawl out of their hole...

It's just a side effect (1)

Opportunist (166417) | 1 year,3 days | (#44855139)

They got so bad teeth that they can't even bite the dust.

Confounding Factors??? (0)

Anonymous Coward | 1 year,3 days | (#44855191)

Observational Studies are no where near being true nor scientific. Sure they're part of the scientific process but they aren't themselves scientific at all. Clinical studies are required. You could just as easily say that Eating less sugar, thus having less tooth cavities, may protect against cancer, or how about brushing your teeth more often may reduces the risk of getting cancer.

Please, for f**ks sake - stop taking shit out of context and drawing up conclusions. Has everyone forgot about the Nurses' Health Study recommending Estrogen to reduce heart disease? That turned out fantastic didn't it? Some clinical studies were discontinued since those taking Estrogen had an 40% increased risk of heart disease. Yet pills were sold and recommended by doctors based on Observational Studies.

Turns out Natural Estrogen is fine and beneficial, particularly in the early stages of menopause. Emphasis on NATURAL Estrogen.

Let's also not forget that this Cavity Cancer relationship study is conducted by JAMA. The same journal that published a similarly biased observational study on Estrogen (Heart and Estrogen-Progestin Replacement Study (HERS)) in the 1990s giving buzz to the Estrogen pills that were in 2002, clinically proven, to be completely false.

http://my.clevelandclinic.org/heart/prevention/estrogen-hormones/default.aspx
http://www.mayoclinic.com/health/hormone-replacement-therapy/WO00131

tonsils? (3, Interesting)

HybridST (894157) | 1 year,3 days | (#44855199)

How many of these people still have their tonsils? I recall reading in one of the journals, probably on arxxiv and phys.org too, that there is some supporting data showing essentially a second immune system just for the mouth.

No link 'cause my google-fu is coffee fueled.

Re:tonsils? (2)

Guppy (12314) | 1 year,3 days | (#44855643)

How many of these people still have their tonsils? I recall reading in one of the journals, probably on arxxiv and phys.org too, that there is some supporting data showing essentially a second immune system just for the mouth.

BTW, what people commonly refer to as "tonsils" are actually just the palatine tonsils, which are part of an entire loose "ring" of lymphoid tissue encircling the pharynx [wikipedia.org] that includes the pharyngeal tonsils (adenoids), tubal tonsils, lingual tonsils, and patchy bits of un-named Mucosa-associated Lymphoid Tissue (MALT) in between.

Confounding Factors_ (2)

Marco Bit (3080425) | 1 year,3 days | (#44855209)

Observational Studies are no where near being true nor scientific. Sure they're part of the scientific process but they aren't themselves scientific at all. Clinical studies are required. You could just as easily say that Eating less sugar, thus having less tooth cavities, may protect against cancer, or how about brushing your teeth more often may reduces the risk of getting cancer. Please, for f**ks sake - stop taking shit out of context and drawing up conclusions. Has everyone forgot about the Nurses' Health Study recommending Estrogen to reduce heart disease? That turned out fantastic didn't it? Some clinical studies were discontinued since those taking Estrogen had an 40% increased risk of heart disease. Yet pills were sold and recommended by doctors based on Observational Studies. Turns out Natural Estrogen is fine and beneficial, particularly in the early stages of menopause. Emphasis on NATURAL Estrogen. Let's also not forget that this Cavity Cancer relationship study is conducted by JAMA. The same journal that published a similarly biased observational study on Estrogen (Heart and Estrogen-Progestin Replacement Study (HERS)) in the 1990s giving buzz to the Estrogen pills that were in 2002, clinically proven, to be completely false.

One clarification (0)

Anonymous Coward | 1 year,3 days | (#44855233)

Confounding factors are in no way related to our founding fathers.

Carcinogenic dental procedures? (3, Insightful)

Nightlight3 (248096) | 1 year,3 days | (#44855253)

It may also be that people who take good care of their teeth, which includes regular dental checkups end up with more x-rays and more exposure to variety of viruses or bacteria which may be carcinogenic (such as HPV, cold sores). Another potential factor is carcinogenicity of the tooth care products, such as toothpastes and mouthwashes. These are couple possibilities that one wouldn't expect research by 'cavity industry' to consider.

Re:Carcinogenic dental procedures? (0)

Anonymous Coward | 1 year,3 days | (#44855563)

Someone actually told me with a straight face that eating sugar fuels cancer cells and that if you did not eat refined sugar you would never get cancer. Reckless headlines like these feed into these crackpot theories and could be potentially dangerous. What if the woman who said this decided to never wear sunscreen because she ate a sugar free diet?

X-rays (2)

jonnat (1168035) | 1 year,3 days | (#44855303)

Or, people with better dental hygiene and less cavities go with much more frequency to dentists, who nowadays won't touch you, even for simple cleaning, without taking X-rays.

Re:X-rays (0)

Anonymous Coward | 1 year,3 days | (#44855919)

Or, people who are more worried about their own physical appearance and hence take better care of their teeth are more sexually promiscuous. We know that sexual promiscuity is associated with HPV carriage (particularly the carcinogenic subtypes) and that increases the risk of cancers at specific sites - cervix, penile, vulva, anus, mouth/throat. Even Michael Douglas knows that!

murky statistics (0)

Anonymous Coward | 1 year,3 days | (#44855399)

Better link at PubMed
http://www.ncbi.nlm.nih.gov/pubmed/24030728

Let's look at some other statistics from the National Cancer Institute
Head and neck cancers account for approximately 3 percent of all cancers in the United States. About 52000 diagnoses in the US in 2012.
- so we're talking about a kind of cancer that is fairly rare (compared to, say, lung, prostate or breast cancer). A 32% reduction in the rate is not a huge change in this context.

"At least 75 percent of head and neck cancers are caused by tobacco and alcohol use"
Hmm, think there's a possibility of confounding factors there?
The patients who died were from 1999 onwards..

Tricky study composition
"Those with a history of cancer, dysplasia, or immunodeficiency or who were younger than 21 years were excluded." Useful for the study, but means that statistics for the study aren't directly applicable to the general population, because people with head/neck cancer in real life often would have *other* cancers.

Interestingly, according to the abstract (the paper is behind a paywall) people who received dental care (crowns, endodontal (e.g. root canal)) had lower incidence of the cancer.

Deliverance (2)

Sponge Bath (413667) | 1 year,3 days | (#44855403)

The hill folk in Deliverance were toothless and playing banjos. Maybe country music prevents cancer.

Mom's Basement (0)

Anonymous Coward | 1 year,3 days | (#44855455)

Nerds who live in Mom's Basement and never get out, just sit there drinking sugary drinks and eating junk food - versus healthy people who eat well, take care of their teeth, and have an active, outdoor lifestyle.

The former have many cavities and fewer instances of cancer owing to their indoor lifestyle. The latter has few or no cavities and more instances of cancer owing to their active, outdoor lifestyle.

Paywalled, once again (0)

Anonymous Coward | 1 year,3 days | (#44855487)

Time and time again, research paid by tax payers is paywalled by parasites...err publishers. But nobody seems to care...

Conclusion: British people don't get cancer :) (1)

JoeyRox (2711699) | 1 year,3 days | (#44855925)

Just sayin...

Instead - heart hisease and Alzheimer's (0)

Anonymous Coward | 1 year,3 days | (#44856475)

Hmmm..I read another article, maybe right here, that showed a strong correlation between tooth and gum disease and heart disease and Alzheimer's.

Given the much lower baseline probability of head/brain cancer, I will continue to brush my teeth.

Money (0)

Anonymous Coward | 1 year,3 days | (#44856807)

People with more money tend to have better dental care.
People with more money tend to have better overall healthcare.
People with better healthcare tend to live longer.
People who live longer are more likely to eventually develop cancer.
Correlation is not causation.

Lets try and express that properly shall we? (0)

Anonymous Coward | 1 year,3 days | (#44857023)

Cavities don't protect against cancer. An interest side effect of not brushing your teeth allows an abundance of tumor slowing chemicals to be secreted by the extra bacteria in your mouth.

That's like seeing penicillin and saying "Eating rotten oranges with fungus on them is a cure for infectious disease!"

Sounds a bit like sickle-cell anaemia (1)

akunak (256682) | 1 year,3 days | (#44857133)

http://en.wikipedia.org/wiki/Sickle-cell_disease [wikipedia.org]

This is a disease (an inherited disease, perhaps like dental caries) that conveys a fitness against something else that is more serious.

Let me interpolate. (1)

Grand Facade (35180) | 1 year,3 days | (#44857245)

Floride causes head and neck cancer.....

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