Emails about fluoride

I recently received an email from a student at one of our local community colleges. The student was taking a journalism course and was writing a story about the “controversy over fluoride.

“Hi my name is **** and I’m a Journalism and Emerging Media student at ***** I’m contacting you in regards to an article I’m doing for my newspaper class on the controversy over fluoride. I was just hoping to ask you a couple questions on the subject of fluoride and I’ll leave them below in this email. The basis of my article is to have a fair and balanced debate between those in the Dental community who support the use of fluoride in our hygiene products/water supplies and arguments made by the anti-fluoridation movement that fluoride causes harm to the body (one website I’ve looked at before is I haven’t had much luck contacting anyone else who would speak with me about this. 


1. Have you heard of the arguments made by anti-fluoridation movement? If so, do you feel they have any merit? If Yes, Why? If No, Why not?

2. Do you have any personal hygiene suggestions for those who would rather not use fluoride based products?

3. As a Dentist do you have patient refusal of fluoride often? If you do, does it change how you approach cleaning their teeth? Or change what products to recommend to them?

4. What advice would you give parents who are worried about their child’s fluoride exposure (regarding hygiene product usage, etc)?

5. Anything else you would like to add?”

Right away my skeptical alert system went off. Lots of peer reviewed research has determined that the use of optimal fluoride concentrations in drinking water is safe and incredibly effective. The CDC called public water fluoridation one of the top 10 public health achievements of the 20th century. By any reasonable standard, there is no scientific controversy about fluoride. I felt it was important that I let this journalism student know what I felt about science journalism and “teaching the controversy” when there isn’t really a controversy.

“Hi *****,

I’m curious about where your research has taken you. I’m wondering what you personally think about fluoride, both systemic and topical. It won’t change how I answer, but it might help me frame where I’m coming from.

A story like this is interesting. Health and science reporting is kind of special. I understand that you want to have a fair and balanced debate. But when you frame it like that, it assumes that both sides of the debate have equal merit. That might work for political stories, or stories about art. It’s not the same for science. Science journalism is special. Often, there aren’t two sides to a story. There’s the side which the science supports and the side of people who don’t like what that science says. These are not viewpoints with equivalent standing. The evidence weight heavily on one side. Unfortunately, people unfamiliar with the scientific process don’t necessarily understand this.

A great example is the “theory of evolution.” The scientific use of “theory” is unfortunate. To lay people, the term “theory” implies that it’s just someone’s best guess of how something happened. That’s not what a scientific theory is. An excellent definition of “scientific theory” is from Wikipedia: ‘A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method, and repeatedly confirmed through observationand experimentation.’ In other words, when scientists use the word theory they mean something that is essentially an explanation of something in the natural world that has been tested and confirmed over and over again. Not just some guy’s idea of how something works.

So I guess what I’m saying is that the fluoride “controversy” isn’t really a controversy. There isn’t credible scientific research that suggests systemic (fluoride in the water) fluoride is dangerous and/or toxic. There is lots of evidence suggesting that systemic fluoride is helpful in preventing tooth decay as well as very cost effective. There’s also lots of evidence suggesting that topical fluoride can help with prevention in tooth decay as well as reversing early “precavitated” lesions.

The problem for a journalist is that doesn’t make for much of a story. The recognized science that includes well designed research says fluoride, when used as directed is safe and effective. If those who believe otherwise have properly designed research published in well peer reviewed journals, the scientific consensus will start to change. Up to now, that’s not been the case.

I’m happy to help, but I want to think a little bit about my answers so I’ll get them to you in a day or so.”

I went ahead and answered her original questions. I answered them in the the way that the current science would indicate. I had done my part by standing on my soapbox and yelling about “teaching the controversy” when there really wasn’t a controversy. This was a college student who didn’t realize they had stumbled upon a dyed-in-the-wool skeptic with a tendency toward rambling emails. Then I received a reply about where this student was coming from.

“My main goal for this article is to basically weigh both sides of the issue and let the audience decide what is best for them and their health. I’m just trying to give each side to the debate a chance to voice their opinion on it. As a journalist I am doing my best to be unbiased while reporting. (As far as me personally),I choose not to use fluoride based toothpaste or mouthwash, and I also have a water bottle that filters fluoride among other things out of my water such as: heavy metals like lead, mercury, radiation etc. I have gone on other websites besides the one I mentioned to research the fluoride debate more. I have contacted the media director for the Fluoride Action Network to get their take on why they believe fluoride is toxic and I was able to get in contact with two Dental Hygienists on what they think. At this point in my life I feel I’ve made the best decision (for me) on fluoride. I understand ‘too much’ fluoride can be toxic, but I’m also told a ‘little bit’ helps our teeth. I just want to make sure all those ‘little bits’ don’t turn into something bigger in the future (If that makes any sense). A main concern to me would be fluorosis of the teeth, and to avoid things like using way more than a pea-size amount. I would just like the opportunity through further exploration finding other ‘all natural’ ways of caring for my mouth.”

So there you have it. As much as I want to believe that this is just a mistake of a somewhat naive college student, I think it’s a bit more than that. In many cases, journalism is about generating a story. The “facts” in this case aren’t hard to find with a little looking. I actually have to give credit to our journalism student for being honest about their biases. Most don’t believe that they have biases. Having biases isn’t a problem. It’s actually part of being human. Recognizing them and overcoming them is really difficult, though. I admit that I struggle with this often. Our aspiring journalist admits that they feel that fluoride isn’t for them. Further, they worry about fluorosis and would prefer a more “all natural” way of caring for their mouth.

Our journalism student commits an “appeal to nature” fallacy here, which is so common that it’s probably not worth dissection. Let’s just say that fluoride is natural, as it is naturally found in most water sources and leave it at that. A bigger problem is our journalist’s concern about fluorosis. Dental fluorosis is a developmental problem. Enamel defects can form in developing teeth if a person is exposed to a high level of fluoride during the time that their teeth are developing. However, it doesn’t effect teeth that have already developed (e.g.–in an adult). This is a fact that can be verified on Wikipedia or any other medical website. Yet our journalist who wants to tell both sides of the story didn’t know that and was, in fact, concerned about it for themselves. A science journalist with clear biases that hasn’t done the basic research can do a lot of damage by simply not knowing the truth about their subject.

On the other hand, the “controversy” is much easier to find. Anti-fluoridation groups make up as much of the first page of a Google search for”water fluoridation” as straight up information sources. The movement against water fluoridation is getting its story out very well, while the boring and decades old success story of public water fluoridation doesn’t have that many blogs and websites dedicated to its advancement. The internet has allowed anyone with an idea and a way to get online the chance to disseminate whatever information they like, whether it is accurate or not.

To their credit our hopeful journalist was seeking out a dentist’s input on fluoride. When asked, “have you heard of the arguments made by the anti-fluoridation movement and do you think they have any merit” I answered like this:

“Yes, I have read about some of the arguments made by the anti-fluoride movement. I think it is legitimate to be concerned about ingesting too much fluoride. But I find most of their arguments to be based in emotion and lacking scientific credibility. Fluoride is present in all water sources. ‘Fluoridation’ is actually more ‘fluoride optimization.’ Some communities with public water supplies have optimized the levels of fluoride in the water supply for dental health. In some cases that means removing fluoride and in some cases that means adding it. Much of the concern of those opposed to fluoride in the water is based upon the idea that it is poisonous and damaging. Fluoride is toxic in chronic high doses. It can cause problems in brain development, problems in bone and tooth development, kidney injury and in certain cases thyroid problems. These injuries happen at high doses over a long period of time. Optimal fluoride (1ppm) is well below a dose that could cause these kinds of problems. Much of what the anti-fluoride groups claim is an extrapolation: since fluoride can cause these problems, it is toxic and poisonous at any level. Toxic effects from anything are dose dependent, and thus optimal fluoridation is safe.

There is overwhelming evidence that optimal fluoride reduces dental disease in a population. Occasionally the anti-fluoride movement will point to research that questions this, but the studies that they tout are usually questionable in their design or interpretation. There is overwhelming scientific support for the use of fluoride in the water supply as safe and effective as well as cost effective on a community wide basis.”

You cannot give “both sides” of a story like this without at least a cursory review of the scientific literature. The water fluoridation issue reminds me a lot of the vaccination issue. For some, the public health gains we’ve achieved with vaccinations are only now being appreciated by people for the fact that many vaccine preventable illnesses are coming back with a vengeance. I only hope that’s not how it goes with public water fluoridation.

Dr. Oz is wrong about amalgam fillings


Dr. Oz is wrong about amalgam fillings. He’s super wrong. He couldn’t be more wrong if his name was W. Wrong Wrongington. An episode of Dr. Oz recently aired where several “experts” weighed in on whether your amalgam fillings are poisoning you. That was the question that all the promos for the show asked: “are your mercury fillings poisoning you?” So I tuned in with bated breath to hear his answer.

His answer, of course, was that yes, they are poisoning you. Seriously, you knew that was the answer, right? If he’s said, “nope, they’re actually pretty safe” that would make the most boring television ever. And Dr. Oz is not about boring TV.

A couple of “experts” weighed in that the problem is the mercury vapor that comes off of silver fillings. According to the experts, any time you contact your teeth together, like chewing or heaven forbid grinding your teeth together, you’re emitting toxic gas into your mouth. That, my friends, is pretty scary stuff. But since you can’t see mercury vapor coming off of your teeth, Dr. Oz and another “expert” did a demonstration to measure how much mercury is released when you brush your teeth.

The demonstration consisted of a plastic model mouth with a bunch of silver fillings in the teeth. The model mouth was kept in a clear box that was ventilated. Dave Wentz, the guy doing the demonstration with Dr. Oz, let everyone know that they do the demonstration in a box so they don’t let any of the toxic mercury out. Which is interesting since it’s very likely that many people in the audience have silver fillings. If they’re that worried about the toxicity of silver filling, wouldn’t they screen the audience to not let folks with toxic fillings in the door? But I digress.

So, they do the demonstration. Dr. Oz puts his hands in the gloves in the clear box and scrubs these amalgam fillings like he’s cleaning the grout in the bathroom tiles. And, low and behold, they measure mercury gas coming off the fillings!

So Dr. Oz is scrubbing away at these silver fillings and asks:

“…at what point should I be concerned. At what [mercury vapor] level is it more than we’re supposed to have?”

Anything over zero is toxic. We’re at 61. 61 micrograms.”

Then Dr. Oz comes up with: “Now how can anyone dispute that there’s no mercury coming off of amalgams?”

And his guest expert Dave Wentz replies. “You can’t. You really can’t.”

If you aren’t careful or observant, this seems like a smoking gun. Amalgam fillings are dangerous and they are poisoning you. I ask you to step back.

The first thing that jumps out at me is the language that is used to frame the discussion. I typically refer to amalgam fillings as “silver fillings.” I never have thought of this as the element silver, but the color of the fillings, when polished is silvery. The Dr. Oz show refers to them as “mercury fillings.” Neither of these terms is probably adequate. Amalgam is a generic term for something that is mixed together. When the term is used in metallurgy it means: “an alloy made with Mercury.” So probably the most accurate term for these fillings would be “amalgam” and not “silver” or “mercury” fillings.

Language matters. When I use the term silver filling I’m indicating the color. When Dr. Oz uses the term mercury filling he’s pointing out the scary, toxic ingredient of the filling. That’s used to frame the discussion, so right away someone who isn’t thinking critically is thinking, “whoa, I didn’t know they placed mercury fillings!”

The next thing that jumps out at me is the way that they created and measured the mercury gas. It is assumed that the model that they offer (a plastic typodont with a ton of silver fillings in a plastic box) is an accurate representation of what’s going on in a human being’s mouth when they have silver fillings and they brush their teeth. I’m not sure it’s fair to assume that for the following reasons:

  • There was no moisture in this model mouth. A normal human being has saliva flow, which keeps the entire mouth moist and lubricated. Moisture on a surface could clearly affect the amount of vapor coming off the surface of a tooth.
  • We don’t know when these fillings were placed, if they were placed correctly, or if they were polished. All of those things can make a difference in the amount of vapor that might come off of these fillings. It wasn’t mentioned on Dr. Oz’s show.
  • We’ll also ignore the fact that the quadrant of fillings he scrubbed had anywhere between 4 and 7 surfaces of amalgam. I did my best to figure out how many surfaces the teeth had but they never showed the far side of the typodont. In any case, that’s quite a bit of amalgam…more than the average patient has for sure.
  • The model had no lips, tongue or cheeks and also wasn’t breathing. Wouldn’t a more accurate measure come from actual patients with actual fillings that were actually brushing their teeth?

They have measured the vapor that comes off of teeth in human models, and it is true that there is a measurable amount. In fact, there’s some question about the most accurate way to measure mercury vapor released from a silver filling. Is the vapor in someone’s breath the most important factor, or would absorbed levels of mercury in urine and blood be the most important measure? The Dr. Oz show wasn’t interested in an actual discussion. They went from “hey look, there’s mercury vapor in this model” to “your fillings are poisoning you.” No mention of actual outcomes based research. No mention of the millions and millions of teeth saved by the use of amalgam fillings with virtually no verifiable reports of bad health outcomes due to amalgam fillings. Clearly the most important message was that there is scary, poisonous vapor coming off of your silver fillings. Awesome.

The final thorn in my side was the statement made by the guest who was putting on the tooth brushing demonstration, Dave Wentz. He says, “anything over zero is toxic.”

Alternative medicine advocates aren’t known for their nuance. Poisons are dose dependent. In other words, something that is harmless in small doses can become harmful in larger doses. That is the case for most things that are known to be toxic to humans. So, how do we know if we’re getting a toxic dose of mercury vapor? Well, the World Health Organization describes a “tolerable intake” of elemental mercury vapor to be 2 micrograms/kg of weight per day. So if we take an average male of 150 lbs, they can tolerate a daily intake of around 136 micrograms of mercury per day. So, are our amalgams delivering that much? The short answer is no. Dr. Oz was able to generate an impressive 61 micrograms by scrubbing on some silver fillings in a box. However, actual measured amounts in human beings are more like 1-3 micrograms per day, depending on how many surfaces of amalgam a patient has.

There are reasons to dislike silver fillings. However, there is no credible evidence that they will cause anyone harm. The outcry by many poorly informed people has led to the outright ban of this material in some countries and the sharp reduction of it’s use here in the United States. Amalgam fillings are durable, long lasting and safe. That’s what credible evidence states. Until credible evidence says otherwise, I think Dr. Oz is wrong. Really wrong. Super duper wrong. His name should be W. Wrong Wrongington.

That last part is just my opinion, though. The rest of it is the truth as we know it.






Meet the new guidelines. Same as the old guidelines.

Yesterday, the American Dental Association and the American Academy of Orthopedic Surgeons released new, evidence based guidelines regarding antibiotic prophylaxis before dental treatment in patients with joint replacements. The press release states that there is no evidence that dental procedures cause joint infections. Prior to this statement, we were to assume that a dental cleaning or placement of a filling had a special and dangerous power to seed the blood with frightening bacteria that somehow knew to go directly to the joint spaces of innocent artificial knees or hips with the malicious intent to infect.

For years I’ve been complaining to anyone who would listen about the joint replacement conundrum. Even though there was no evidence that premedicating patients was doing anyone any good, we did it. Because giving a patient a giant dose of antibiotics before having dental treatment is a much better option than having to treat or replace an infected joint, right? So just shut up and give them the antibiotics, Doc.

And that’s what we do. Each time I consult with a patient’s surgeon I get similarly frustrated. Some surgeons want premedication for the the rest of the patient’s life. Some surgeons want 6 months. Some want 2 years. Some think Amoxicillin is the way to go. Some say it’s Keflex or nothing. The one thing that all surgeons agree on is that they aren’t going to write the prescription for the antibiotics. That’s the job of the dentist. Which also means it’s the liability of the dentist. Let’s face it. Some patients can develop hypersensitivity to antibiotics and a huge dose of antibiotics could cause a reaction. Even a potentially severe reaction. And no one wants to be the one who wrote that script, right?

Let’s just get this out of the way. Most dentists don’t believe we’re doing a valuable service by premedicating our patients. Most of us know that eating a Dorito is at least as great of a risk as a dental cleaning for seeding the blood with oral bacteria. But we’re not rushing to premedicate patients prior to Dorito consumption. We’re doing it to cover our asses! We’ve been trained to cover our asses about this stuff since dental school. It has nothing to do with excellent patient care and everything to do with making sure we did everything right so that if some future joint infection or infective endocarditis event comes along we can prove that “it wasn’t us.” If it was really about excellent patient care, we’d have the ADA lobbying Frito Lay to bring out “Blazin’ Amoxicillin” Doritos.

I’m a dentist. My strength is treating dental disease. I’m a pretty smart guy, but frankly I’m not really up on the real risks of artificial joint infection or antibiotic allergies. How can I be expected to weigh the likelihood of two incredibly rare but very serious outcomes (joint infection vs. antibiotic reaction)? I don’t think it’s legitimate for the dentist to have their own policy. How about if the professional group that represents me, the American Dental Association, gives me some solid guidance so I don’t have to worry that I’ll be 1) harming my patients by not correctly weighing the risk factors and 2) you know…the lawyers.

But now, the evidence (or lack thereof) is in! We can stop worrying about the premedication for people with joint replacements because there’s no evidence of harm, right? 

Ummm. No.

What the joint ADA-AAOS actually gives us are 3 “guideline recommendations.”

But recommendations are good, right? After all, the American Heart Association passed down (many times!) their recommendations on stone tablets for all dentists to know and heed! And by following recommendations it means that the lawyers can’t get us! I mean, as long as we follow the recommendations!  

You’d think so. I mean, you’d think that having recommendations from the two big professional groups representing dentists and orthopedic surgeons would give us actual guidance on this issue. But it’s just not true.

The ADA-AAOS statement made me skeptical almost as soon as I started reading.

This summary of recommendations is not intended to stand alone. Treatment decisions should be made in light of all circumstances presented by the patient. Treatments and procedures applicable to the individual patient rely on mutual communication between patient, physician, dentist and other healthcare practitioners.

I read that and think, “these guidelines are perfectly fine, except you still have to evaluate patients on a case by case basis and if you get sued, we don’t have your back.”

I have to admit that I haven’t taken the time to read the full guideline, so my comments are based on the summary. The full guideline is somewhere around 100 pages and my own inability to concentrate for that length of time (thanks, internet!) has kept me from reading it. If someone does read it and find that I’m completely wrong, please let me know. I’d love to be wrong about this.

The recommendations strike me as incredibly watered down. They seem to be written as obliquely and indirectly as possible. Then each of them is given a “strength of recommendation” rating which means nothing to me. And they know this. So they give a definition about the strength of rating. Right after they give the strength of the rating. Honestly, it’s kind of bizarre.

The first recommendation addresses the use of prophylactic antibiotics:

The practitioner might consider discontinuing the practice of routinely prescribing prophylactic antibiotics for patients with hip and knee prosthetic joint implants undergoing dental procedures.

I might consider discontinuing antibiotics. Sure. I might. I might consider explaining my position to the patient, too. I mean they are the ones that are taking the very slight (but real!) risk here. But did I really need a recommendation from the ADA and the AAOS to tell me that I might think about it?

Further bolstering my opinion of this recommendation is the “strength of recommendation” score it’s given: “limited.”

A Limited recommendation means the quality of the supporting evidence that exists is unconvincing, or that well-conducted studies show little clear advantage to one approach versus another.

Practitioners should be cautious in deciding whether to follow a recommendation classified as Limited, and should exercise judgment and be alert to emerging publications that report evidence. Patient preference should have a substantial influencing role.

Recommendation 2 speaks to the use of preoperative topical oral antimicrobials:

We are unable to recommend for or against the use of topical oral antimicrobials in patients with prosthetic joint implants or other orthopaedic implants undergoing dental procedures.

So, they won’t say whether use of chlorhexidine prior to your filling is worth it or not. Great. Thanks for that. This strikes me as unnecessary because the risk profile of a swish of Peridex is a lot less than a megadose of Amoxicillin. In any case, they want us to know that we should feel “little contraint” in deciding whether to follow this recommendation. Gee, thanks.

Finally, the most bizarre recommendation.

In the absence of reliable evidence linking poor oral health to prosthetic joint infection, it is the opinion of the work group that patients with prosthetic joint implants or other orthopaedic implants maintain appropriate oral hygiene.

Really? Was there a time when I was supposed to be telling joint replacement patients that the risk of joint infection was so great that the shouldn’t floss? Or am I to assume that the ADA and AAOS feel that maintaining oral hygiene is vital to the health of an artificial joint? Honestly, I don’t even know what they’re trying to say. But at least they all agree on it. They give this recommendation a strength of: “consensus.”

A Consensus recommendation means that expert opinion supports the guideline recommendation even though there is no available empirical evidence that meets the inclusion criteria.

I had high hopes that the ADA would come through for us on this issue. I was hoping for an “AHA-like” guideline that would take the guessing out of this very common event for dental patients and dentists alike. It didn’t happen.

The most hopeful statement I got from the new guidelines is this:

Patient preference should have a substantial influencing role.

Although this statement was made specifically in reference to recommendation 2, I think it’s worth contemplating for the whole thing. Taking a large dose of antibiotics prior to dental appointments is not a risk-free event. I honestly don’t know if the data exists to weight the risk of taking antibiotics against the risk of joint infection at the dental office. I think patients can and should be part of the decision here.

The whole inconclusive data issue cuts both ways. Sure, there is no data to conclude that dental treatment causes joint infections. However, outside interests can just as easily claim that there isn’t data that dental treatment doesn’t cause infection in artificial joints. As a profession, we’re in the exact same spot that we were before these so called recommendations came out. We’re still going to cover our asses for the wrong reasons. It wasn’t good medicine before and it still isn’t.

What do I think should happen? I think the ADA and AAOS should sound off like they’ve got a pair. I think they should put a statement out that they’re going to help fund research on this topic to really answer the question and in the mean time they need to make a statement to dentists that “this is the recommendation and we’ve got your back if there’s a problem.” I think that the ADA should set aside a fund for the inevitable legal challenges that will come along to such a definitive statement and let member dentist’s know that they will be represented. It’s time to do the right thing for the right reason.

Am I right on the money? Am I completely dead wrong? I’d like to hear what you think. Feel free to leave a comment here or email me at