Psycho-Babble Medication Thread 223248

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Re: Dental Amalgam, and paranoia » mattdds

Posted by leeran on April 30, 2003, at 21:05:40

In reply to Dental Amalgam, and paranoia » leeran, posted by mattdds on April 30, 2003, at 19:07:31

Matt,

Thank you for your concern.

One of my links was invalid due to a double quote I added at the end.

http://www.epa.gov/seahome/mercury/src/ways.htm

The last paragraph from this EPA (Environmental Protection Agency, a government run agency here in the United States), link states the following (I am referencing the last sentence in particular):

"Humans are exposed to mercury primarily through ingestion of fish that contain methylmercury. Inhalation of mercury vapors is a potential occupational risk in industries that process or use mercury. Skin contact with materials containing organic mercury and elemental mercury may also result in mercury exposure. People with dental amalgams that contain mercury have greater exposure."

It doesn't state "may" have greater exposure. I took that into careful consideration when making my decision.

Perhaps you didn't have time to read my post closely. I am having a broken molar repaired as well as the tooth in front of it. Two repairs. No one has suggested the complete removal of my amalgam fillings, nor have I requested that procedure.

I researched my dentist thoroughly before choosing him from the list of providers who are covered by my family's insurance plan. I research everything that I feel might have an impact on my family, health, finances or future, i.e. my psychiatrist, the medications Lexapro, Wellbutrin, my son's prospective high school before we moved, stocks, savings accounts, etc.

I don't believe that either one of my posts indicated that I was advocating any action on anyone else's part regarding their choices in dental care. Someone asked a question, and I responded based on my recent experience.

As an aside, I live in California. This state requires posting notices in environments where dangerous materials are used. For example, in dry cleaners, on lead china as well as in dental offices (or anywhere else a material is used that is labeled as toxic).

My dentist is not a someone suggesting a "quack-o" procedure, as you put it.

He is a professor at a major university in Southern California, considered to be one of the leading private research universities in the world. He also has a large dental practice in this area and has been in the dental profession for about thirty years.

The proposed plan of treatment, which includes two porcelain fillings, was his diagnosis. I had never even heard much about the amalgam filling debate until I followed a link from this board to a website regarding magnesium and depression.

That said, I did not mention any fear I may have of mercury or the desire to have any and all of my fillings replaced during my visit. I usually leave the diagnosis to the doctor/dentist.

Although I respect the American Dental Association's position on amalgam fillings, I do not adopt a profession's beliefs just because they say it is so. As a consumer, I consider it my option to investigate anything on which I choose to spend my money, including health care.

Given my dentist's proposed plan of treatment I came home and decided to review my options from what I considered reliable sources (the FDA, the EPA and others) before making my final decision.

To be honest, I felt that your post seemed to be leaning toward an implication that I'm paranoid or that I'm advocating the notion that people adopt certain behaviors based on my own beliefs - which couldn't be farther from the truth.

From what I've observed on these boards, people are free to offer up suggestions, links, and ask questions with the natural assumption that no one is trying to push anything off on anyone else(medications, advice, natural remedies, etc.)

As for Hal Huggins, I have no idea who he is or what point you were trying to make.

Lee

 

Dental amalgam, again » leeran

Posted by mattdds on May 1, 2003, at 21:05:46

In reply to Re: Dental Amalgam, and paranoia » mattdds, posted by leeran on April 30, 2003, at 21:05:40

Lee,

My apologies!

You're right, perhaps I misunderstood, and just assumed (wrongly) that you were getting amalgam removed because you thought it would help with depression or bipolar. This was the topic being discussed in the thread, so I wrongly assumed that was what you were talking about. I did read your post briefly, and probably made too many assumptions (and we all know what happens when we make those, haha).

If you are just getting teeth repaired because they are broken (you said a molar broke?), then that changes things. When teeth break, an onlay or a crown is usually indicated, and amalgam is generally a poor choice anyway. Amalgam is only used for direct onlays when that is the only option economically for a patient. Otherwise, onlays with noble metals (e.g. gold), or porcelain is the way to go for molars. So, why did you go through all the research on amalgam then? Did your dentist present an amalgam onlay as a treatment option?

Not to meddle, but did you discuss a gold onlay with your dentist? They are wonderful and last an incredibly long time. They also do not fracture, and wear opposing dentition as porcelain does.

When you say porcelain filling, do you mean a porcelain onlay or inlay, or crown? I have never heard of porcelain "fillings". Plus, if your tooth "broke" as you say, it doesn't sound like you need a filling. And what happened to the tooth in front of it? Why are you removing that amalgam?

Porcelain is a very inert and highly esthetic material (though it does have a tendency to fracture, and wears the opposing dentition, which I imagine your dentist took into consideration when treatment planning - I hope you dont grind your teeth!). Porcelain is a great material when used in the right places.

In my opinion, the health scare about amalgam are misguided. This was not implying at all that you are paranoid, but was responding to the (in my opinion, paranoid) anti-amalgam movement that the thread was discussing. I apologize if it sounded like I was calling you paranoid. I was not.

The dentist you describe sounds very qualified. That's great! Sounds like he has some neat accomplishments. However, I'm almost sure if you ask him, he will agree that having amalgam removed for purported health benefits is indeed quackery (I understand now that he is just repairing teeth, not suggesting you remove amalgam to improve your mood or health, right?). At least this is what I have been taught by countless similarly qualified dentists, although they practice in Manhattan, and teach at Columbia University, not in Southern California, so the philosophy may differ over there. I do know that the overwhelming majority of researchers feel that removing dental amalgam for health reasons is a "quack-o" procedure. The same majority is also convinced it is very safe in dental restorations.

In your first post, you wrote:

>>I had a molar with an amalgam filling break in March and I have not felt good since then.

Then you said that you did not know whether you felt bad because it was the anxiety of a tooth broken or the mercury. For whatever my opinion is worth, I strongly suspect it is the former.

You are absolutely right, mercury IS a neurotoxin, at high enough doses. But the amounts released by dental amalgam do not reach these high levels (unless you remove them, then the levels get higher, but still probably not neurotoxic). That is the message I was trying to get across, although I did it ineffectively, and came across a bit rude. I apologize for that.

Best of luck,

Matt

P.S. FYI, Hal Huggins is a dentist who advocates removing all your dental amalgam to improve systemic diseases such as depression, multiple sclerosis, and Parkinsons. Another poster brought up his name, so I thought you might have heard of him. Again, bad assumption on my part.

 

Re: Dental Amalgam, and paranoia

Posted by Katia on May 3, 2003, at 3:57:50

In reply to Re: Dental Amalgam, and paranoia » mattdds, posted by leeran on April 30, 2003, at 21:05:40

HI!
I had to respond. Itried to read all the links before responding,but coulnd'tbefore going cross-eyed!

i simply want to state my own experience with this and it is:
replacing the mercury in my mouth four years ago was just another sub/unconscious way i'd been dealing with a depression. I lived for so long with depression and didn't know "it" as such that i've tried every "new age" every holistic thing energy healing thing I could come across w/out realizing that I was trying to heal depression. Anyway, since replacingthose fillings, i've only experienced worse depression. everyone's different and maybe I'vedonesomethinggood for me in the longrun, but for depression it didn'tseemto work forme!
katia

 

Re: Dental mercury is a real threat (long)

Posted by Larry Hoover on May 3, 2003, at 12:36:56

In reply to Dental Fillings, posted by David Smith on April 29, 2003, at 19:31:44

> Does this information sound credible to anyone?
> Thanks.
>
> http://www.yourhealthbase.com/amalgams.html

Yes, it sounds credible.

About Quackwatch: Dr. Barrett, the dude who runs the site, has been successfully sued for providing biased and defamatory information. Take him with a grain of salt. He generally ignores any science that doesn't fit with his preconceived notions. That's not to say that he's always wrong, but he is often so.

I spent quite a while investigating mercury, and amalgam fillings, as part of a toxicological background study for the World Wildlife Fund. There is *no* safe exposure to mercury, in my perhaps not so humble opinion. Even arsenic (another toxic heavy metal in the same reactivity group as mercury) may be conditionally essential for health (in tiny amounts), but there has never been any evidence that mercury serves any health-giving role. Quite the contrary.

So-called silver amalgams are about 50% by weight in mercury. The mercury is not chemically bound to the other metals; in fact, the other metals are in solution and crystallized in the mercury. There are a number of mechanical (e.g. chewing, bruxism), physical (e.g. hot beverages, saliva), and chemical (saliva again, and bacterial action) processes which liberate mercury from the surface of the amalgam. It is quite possible that mercury vapour is absorbed directly into the brain across the membranes of the naso-pharynx, and via the lungs. Swallowed mercury is less well absorbed, but bacterial transformation in the gut converts it to methyl mercury, which *is* readily absorbed.

You're not going to avoid mercury. General distribution of mercury is increasing in all areas of the environment, most particularly from industrial activity (especially coal burning). What you can do is try to limit exposures in any way you can.

A little bit about mercury toxicology.....

First, about organic mercury, from:
http://www.ansci.cornell.edu/courses/as625/1998term/Cadmium/cadmium.html
"Mercury (MeHg) (and perhaps Hg 2+) exerts its toxic effects through
numerous mechanisms. In neurons, MeHg disrupts calcium homeostasis by
affecting both voltage-gated calcium channels as well as disruption of
intracellular pools. MeHg, like cadmium, binds to sulfydral groups on
cysteine, which may compromise the function of enzymes and ion channels.
MeHg also interacts with DNA and RNA, resulting in reductions in protein
synthesis, and disrupts the structure of the microtubules of neurons. MeHg
poisoning produces oxidative stress in cells. This may occur through
multiple mechanisms: decreased expression and activity of anti-oxidant
enzymes, participation in a Fenton-like reaction by Hg 2+, or disruption of
electron transport in the mitochondria through inhibition of enzymes of the
electron transport chain, and subsequent uncoupling of the e- transport
chain and ATP synthesis (oxidative phosphorylation). Methylmercury has also
been shown to induce programmed cell death (apoptosis) in exposed neurons."

Inorganic mercury, as found in amalgams:
http://www.calpoison.org/public/mercury.html
"Long-term exposure (usually work-related) of inhaled vapors is generally
more dangerous than a one-time short exposure. After long-term inhalation
exposure, the nervous system is the main target of toxicity. Symptoms may
occur within weeks but usually develop insidiously over a period of years.
Neurologic symptoms include tremors, headaches, short-term memory loss,
incoordination, weakness, loss of appetite, altered sense of taste and
smell, numbness and tingling in the hands and feet, insomnia, and excessive
sweating. Psychiatric effects are also seen after long-term exposure."

From the Agency for Toxic Substances and Disease Registry:
http://www.atsdr.cdc.gov/ToxProfiles/phs8916.html
"A potential source of exposure to metallic mercury for the general
population is mercury released from dental amalgam fillings. An amalgam is
a mixture of metals. The amalgam used in silver-colored dental fillings
contains approximately 50% metallic mercury, 35% silver, 9% tin, 6% copper,
and trace amounts of zinc. When the amalgam is first mixed, it is a soft
paste which is inserted into the tooth surface. It hardens within 30
minutes. Once the amalgam is hard, the mercury is bound within the amalgam,
but very small amounts are slowly released from the surface of the filling
due to corrosion or chewing or grinding motions. Part of the mercury at the
surface of the filling may enter the air as mercury vapor or be dissolved in
the saliva. The total amount of mercury released from dental amalgam
depends upon the total number of fillings and surface areas of each filling,
the chewing and eating habits of the person, and other chemical conditions
in the mouth. Estimates of the amount of mercury released from dental
amalgams range from 3 to 17 micrograms per day (µg/day). The mercury from
dental amalgam may contribute from 0 to more than 75% of your total daily
mercury exposure, depending on the number of amalgam fillings you have, the
amount of fish consumed, the levels of mercury (mostly as methylmercury) in
those fish, and exposure from other less common sources such as mercury
spills, religious practices, or herbal remedies that contain mercury."

Amalgam that is left over after a filling is prepared is considered toxic waste, and must be handled under strictly controlled conditions. How is it that amalgam in the mouth, where it is exposed to a variety of degradative processes, is non-toxic? Think about the brilliance of the first dentist who used it: "Duh! I know! Let's store mercury in people's mouths, and we'll tell them it's safe."

At the risk of being excessively long-winded, I'll move on to references you may want to consider.

I'm only home for a few minutes to get a shower, so I won't be around till Wednesday or so.

Lar


Altern Med Rev 1998 Aug;3(4):262-70 Related Articles, Books, LinkOut


Cysteine metabolism and metal toxicity.

Quig D.

Doctor's Data, Inc., West Chicago, IL, USA. dquig@doctorsdata.com

Chronic, low level exposure to toxic metals is an increasing global problem. The symptoms associated with the slow accumulation of toxic metals are multiple and rather nondescript, and overt expression of toxic effects may not appear until later in life. The sulfhydryl-reactive metals (mercury, cadmium, lead, arsenic) are particularly insidious and can affect a vast array of biochemical and nutritional processes. The primary mechanisms by which the sulfhydryl-reactive metals elicit their toxic effects are summarized. The pro-oxidative effects of the metals are compounded by the fact that the metals also inhibit antioxidative enzymes and deplete intracellular glutathione. The metals also have the potential to disrupt the metabolism and biological activities of many proteins due to their high affinity for free sulfhydryl groups. Cysteine has a pivotal role in inducible, endogenous detoxication mechanisms in the body, and metal exposure taxes cysteine status. The protective effects of glutathione and the metallothioneins are discussed in detail. Basic research pertaining to the transport of toxic metals into the brain is summarized, and a case is made for the use of hydrolyzed whey protein to support metal detoxification and neurological function. Metal exposure also affects essential element status, which can further decrease antioxidation and detoxification processes. Early detection and treatment of metal burden is important for successful detoxification, and optimization of nutritional status is paramount to the prevention and treatment of metal toxicity.

Altern Med Rev 1998 Jun;3(3):199-207 Related Articles, Books, LinkOut


Dimercaptosuccinic acid (DMSA), a non-toxic, water-soluble treatment for heavy metal toxicity.

Miller AL.

Alternative Medicine Review. P.O. Box 25, Dover, ID 83825, USA. alan@thorne.com

Heavy metals are, unfortunately, present in the air, water, and food supply. Cases of severe acute lead, mercury, arsenic, and cadmium poisoning are rare; however, when they do occur an effective, non-toxic treatment is essential. In addition, chronic, low-level exposure to lead in the soil and in residues of lead-based paint, to mercury in the atmosphere, in dental amalgams and in seafood, and to cadmium and arsenic in the environment and in cigarette smoke is much more common than acute exposure. Meso-2,3-dimercaptosuccinic acid (DMSA) is a sulfhydryl-containing, water-soluble, non-toxic, orally-administered metal chelator which has been in use as an antidote to heavy metal toxicity since the 1950s. More recent clinical use and research substantiates this compound s efficacy and safety, and establishes it as the premier metal chelation compound, based on oral dosing, urinary excretion, and its safety characteristics compared to other chelating substances.

Int Arch Occup Environ Health 1994;66(3):209-12 Related Articles, Books, LinkOut


Long-term mercury excretion in urine after removal of amalgam fillings.

Begerow J, Zander D, Freier I, Dunemann L.

Medizinisches Institut fur Umwelthygiene, Dusseldorf, Germany.

The long-term urinary mercury excretion was determined in 17 28- to 55-year-old persons before and at varying times (up to 14 months) after removal of all (4-24) dental amalgam fillings. Before removal the urinary mercury excretion correlated with the number of amalgam fillings. In the immediate post-removal phase (up to 6 days after removal) a mean increase of 30% was observed. Within 12 months the geometric mean of the mercury excretion was reduced by a factor of 5 from 1.44 micrograms/g (range: 0.57-4.38 micrograms/g) to 0.36 microgram/g (range: 0.13-0.88 microgram/g). After cessation of exposure to dental amalgam the mean half-life was 95 days. These results show that the release of mercury from dental amalgam contributes predominantly to the mercury exposure of non-occupationally exposed persons. The exposure from amalgam fillings thus exceeds the exposure from food, air and beverages. Within 12 months after removal of all amalgam fillings the participants showed substantially lower urinary mercury levels which were comparable to those found in subjects who have never had dental amalgam fillings. A relationship between the urinary mercury excretion and adverse effects was not found. Differences in the frequency of effects between the pre- and the post-removal phase were not observed.
J Toxicol Clin Toxicol 2000;38(7):697-700 Related Articles, Books, LinkOut


Urinary excretion of trace elements in humans after sodium 2,3-dimercaptopropane-1-sulfonate challenge test.

Torres-Alanis O, Garza-Ocanas L, Bernal MA, Pineyro-Lopez A.

Centro Antivenenos, Departamento de Farmacologia y Toxicologia, Facultad de Medicina, Universidad Autonoma de Nuevo Leon, Monterrey Nuevo Leon, Mexico. otorres@ccr.dsi.uanl.mx

OBJECTIVE: To evaluate the effects of intravenous sodium 2,3-dimercaptopropane-1-sulfonate (DMPS, Dimaval) on urinary excretion of essential trace elements in subjects who received this chelating agent as a mercury challenge test. SUBJECTS: Eleven subjects sought medical attention due to concern with the toxicity of mercury released from dental amalgam fillings. DESIGN: The subjects were given DMPS 3 mg/kg intravenously. Spot urine samples were collected 1 hour before and 1 hour after the DMPS dose for laboratory analysis. In addition to mercury, the urinary excretion of copper, zinc, selenium, magnesium, manganese, molybdenum, chromium, cobalt, and aluminum were measured. RESULTS: A significant increase in urinary excretion of mercury (3- to 107-fold) was observed after the DMPS dose. The DMPS treatment led to a 2- to 119-fold increase in copper excretion; 3- to 43.8-fold in selenium excretion; 1.6- to 44-fold in zinc excretion; and 1.75- to 42.7-fold in magnesium excretion. The excretion of manganese, chromium, cobalt, aluminium, and molybdenum remained unchanged. CONCLUSIONS: In this study, an intravenous DMPS challenge test produced a significant increase in mercury excretion and also led to an increased excretion of copper, selenium, zinc, and magnesium.

Occup Environ Med 1995 Feb;52(2):124-8 Related Articles, Books, LinkOut


People with high mercury uptake from their own dental amalgam fillings.

Barregard L, Sallsten G, Jarvholm B.

Department of Occupational Medicine, Sahlgrenska University Hospital, Goteborg, Sweden.

OBJECTIVES--To describe people with high mercury (Hg) uptake from their amalgam fillings, and to estimate the possible fraction of the occupationally unexposed Swedish population with high excretion of urinary Hg. METHODS--Three case reports are presented. The distribution of excretion of urinary Hg in the general population was examined in pooled data from several sources. RESULTS--The three cases excreted 23-60 micrograms of Hg/day (25-54 micrograms/g creatinine), indicating daily uptake of Hg as high as 100 micrograms. Blood Hg was 12-23 micrograms/l, which is five to 10 times the average in the general population. No other sources of exposure were found, and removal of the amalgam fillings resulted in normal Hg concentrations. Chewing gum and bruxism were the probable reasons for the increased Hg uptake. Extrapolations from data on urinary Hg in the general population indicate that the number of people with urinary excretion of > or = 50 micrograms/g creatinine could in fact be larger than the number of workers with equivalent exposure from occupational sources. CONCLUSION--Although the average daily Hg uptake from dental amalgam fillings is low, there is a considerable variation between people; certain people have a high mercury uptake from their amalgam fillings.

J Dent Res 1998 Apr;77(4):615-24 Related Articles, Books, LinkOut


Mercury in biological fluids after amalgam removal.

Sandborgh-Englund G, Elinder CG, Langworth S, Schutz A, Ekstrand J.

Department of Basic Oral Sciences, Karolinska Institutet, Huddinge, Sweden.

Dental amalgam is the major source of inorganic mercury (Hg) exposure in the general population. The objective of the present study was to obtain data on changes in Hg levels in blood, plasma, and urine following removal of all amalgam fillings during one dental session in 12 healthy subjects. The mean number of amalgam surfaces was 18 (range, 13 to 34). Frequent blood sampling and 24-hour urine collections were performed up to 115 days after amalgam removal, and in eight subjects additional samples of plasma and urine were collected up to three years after amalgam removal. A transient increase of Hg concentrations in blood and plasma was observed within 48 hours after amalgam removal. In plasma, the peak concentrations significantly exceeded the pre-removal plasma Hg levels by, on average, 32% (1.3 nmol/L; range, 0.1 to 4.2). No increase in the urinary Hg excretion rate was apparent after amalgam removal. An exponential decline of Hg was seen in all media. Sixty days after the amalgam removal, the Hg levels in blood, plasma, and urine had declined to approximately 60% of the pre-removal levels. In seven subjects, who were followed for up to three years, the half-lives of Hg in plasma and urine were calculated. In plasma, a bi-exponential model was applied, and the half-life was estimated at median 88 days (range, 21 to 121). The kinetics of Hg in urine (nmol/24 hrs) fit a mono-exponential model with a median half-life of 46 days (range, 35 to 67). It is concluded that the process of removing amalgam fillings can have a considerable impact on Hg levels in biological fluids. After removal, there was a considerable decline in the Hg levels of blood, plasma, and urine, which slowly approached those of subjects without any history of amalgam fillings.

J Dent Res 1985 Aug;64(8):1069-71 Related Articles, Links


Intra-oral air mercury released from dental amalgam.

Vimy MJ, Lorscheider FL.

Intra-oral air was analyzed for mercury (Hg) vapor concentration in 46 subjects, 35 of whom had dental amalgam restorations. Measurements were made with a Jerome Hg detector both before and ten min after chewing stimulation. Subjects with dental amalgams had unstimulated Hg vapor concentrations that were nine times greater than basal levels in control subjects with no amalgams. Chewing stimulation in subjects with amalgams increased their Hg concentration six-fold over unstimulated Hg levels, or a 54-fold increase over levels observed in control subjects. Concentrations of Hg measured in intra-oral air larger than those reported in expired air were attributed to the rate and direction of air passage across amalgam surfaces. There were significant correlations between Hg vapor released into intra-oral air after chewing stimulation and the numbers and types of amalgam restorations. It is concluded that intraoral air is a reliable physiological indicator of Hg released from dental amalgam that may reflect a major source of chronic Hg exposure.

J Dent Res 1985 Aug;64(8):1072-5 Related Articles, Links


Serial measurements of intra-oral air mercury: estimation of daily dose from dental amalgam.

Vimy MJ, Lorscheider FL.

Serial measurements of Hg concentration in intra-oral air were made during and after chewing stimulation in 35 subjects with occlusal amalgam restorations. Hg concentrations remained elevated during 30 min of continuous chewing and declined slowly over 90 min after cessation of chewing. By curve-fitting and integration analysis of data during these time periods (including corrections for respiratory volume, retention rate of inspired Hg, oral-to-nasal breathing ratios, and consumption of three meals and three snacks per day), we calculated that all subjects received an average daily Hg dose of approximately 20 micrograms. Subjects with 12 or more occlusal amalgam surfaces were estimated to receive a daily Hg dose of 29 micrograms, whereas in subjects with four or fewer occlusal amalgam surfaces, the dose was 8 micrograms. These Hg dosages from dental amalgam were as much as 18-fold the allowable daily limits established by some countries for Hg exposure from all sources in the environment. The results demonstrate that the amount of elemental Hg released from dental amalgam exceeds or comprises a major percentage of internationally accepted threshold limit values for environmental Hg exposure. It is concluded that dental amalgam Hg makes a major contribution to total daily dose.

Clin Prev Dent 1991 May-Jun;13(3):5-7 Related Articles, Links


Long-term dissolution of mercury from a non-mercury-releasing amalgam.

Chew CL, Soh G, Lee AS, Yeoh TS.

National University of Singapore.

The hazards of mercury from dental amalgams have long been recognized. This study examined the mercury release from a "non-mercury-releasing" dental amalgam, Composil, over a 104-week period. Four cylindrical specimens were incubated in 10 ml of purified water at 37 degrees C. The incubate was changed at the end of each 24-hour period and assayed for its mercury content at biweekly intervals. Mercury estimation was carried out using cold-vapor, atomic absorption spectrophotometry over a 104-week period. Results showed that the overall mean release of mercury was 43.5 +/- 3.2 micrograms/cm2/24 hr, and the amount of mercury released remained fairly constant during the duration of the experiment. This study showed that Composil releases mercury in quantities that far exceed those detected in other amalgam systems.
J Prosthet Dent 1987 Dec;58(6):704-7 Related Articles, Links


Correlation of dental amalgam with mercury in brain tissue.

Eggleston DW, Nylander M.

Department of Restorative Dentistry, University of Southern California, School of Dentistry, Los Angeles.

Data from this project demonstrate a positive correlation between the number of occlusal surfaces of dental amalgam and mercury levels in the brain (p less than .0025 in white matter). This is indirect evidence suggesting that mercury from dental amalgam fillings may contribute to the body burden of mercury in the brain. The toxic levels of mercury in human tissues have not been sufficiently investigated and the amount of mercury in human brain tissue from dental amalgam may or may not be clinically significant. Nevertheless, dental amalgam exposure should be considered in monitoring sources of mercury accumulation in human brain tissue.

Caries Res 2001 May-Jun;35(3):163-6 Related Articles, Links


Dental amalgam fillings and the amount of organic mercury in human saliva.

Leistevuo J, Leistevuo T, Helenius H, Pyy L, Osterblad M, Huovinen P, Tenovuo J.

The National Public Health Institute, Antimicrobial Research Laboratory, Turku University, Turku, Finland.

We studied differences in the amounts of organic and inorganic mercury in saliva samples between amalgam and nonamalgam human study groups. The amount of organic and inorganic mercury in whole saliva was measured in 187 adult study subjects. The mercury contents were determined by cold-vapor atomic absorption spectrometry. The amount of organic and inorganic mercury in paraffin-stimulated saliva was significantly higher (p<0.001) in subjects with dental amalgam fillings (n = 88) compared to the nonamalgam study groups (n = 43 and n = 56): log(e) (organic mercury) was linearly related to log(e) (inorganic mercury, r(2) = 0.52). Spearman correlation coefficients of inorganic and organic mercury concentrations with the number of amalgam-filled tooth surfaces were 0.46 and 0.27, respectively. Our results are compatible with the hypothesis that amalgam fillings may be a continuous source of organic mercury, which is more toxic than inorganic mercury, and almost completely absorbed by the human intestine.

FASEB J 1994 Nov;8(14):1183-90 Related Articles, Links


Adverse immunological effects and autoimmunity induced by dental amalgam and alloy in mice.

Hultman P, Johansson U, Turley SJ, Lindh U, Enestrom S, Pollard KM.

Department of Pathology, Linkoping University, Sweden.

Dental amalgam fillings are the most important source of mercury exposure in the general population, but their potential to cause systemic health consequences is disputed. In this study, inbred mice genetically susceptible to mercury-induced immune aberrations were used to examine whether dental amalgam may interfere with the immune system and cause autoimmunity. Female SJL/N mice were implanted in the peritoneal cavity with 8-100 mg silver amalgam or silver alloy for 10 weeks or 6 months. Chronic hyperimmunoglobulinemia, serum IgG autoantibodies targeting the nucleolar protein fibrillarin, and systemic immune-complex deposits developed in a time- and dose-dependent manner after implantation of amalgam or alloy. Splenocytes from mice implanted with amalgam or alloy showed an increased expression of class II molecules. The functional capacity of splenic T and B cells was affected in a dose-dependent way: 10 weeks of low-dose and 6 months of high-dose amalgam implantation strongly increased mitogen-induced T and B cell proliferation, whereas 10 weeks of high-dose implantation decreased the proliferation. Not only mercury but also silver accumulated in the spleen and kidneys after amalgam implantation. In conclusion, dental amalgam implantation in a physiological body milieu causes chronic stimulation of the immune system with induction of systemic autoimmunity in genetically sensitive mice. Implantation of silver alloy not containing mercury also induced autoimmunity, suggesting that other elements, especially silver, have the potential to induce autoimmunity in genetically susceptible vertebrates. Accumulation of heavy metals, from dental amalgam and other sources, may lower the threshold of an individual metal to elicit immunological aberrations. We hypothesize that under appropriate conditions of genetic susceptibility and adequate body burden, heavy metal exposure from dental amalgam may contribute to immunological aberrations, which could lead to overt autoimmunity.

FASEB J 1990 Nov;4(14):3256-60 Related Articles, Links


Comment in:
FASEB J. 1991 Feb;5(2):236.

Whole-body imaging of the distribution of mercury released from dental fillings into monkey tissues.

Hahn LJ, Kloiber R, Leininger RW, Vimy MJ, Lorscheider FL.

Department of Radiology, University of Calgary, Faculty of Medicine, Alberta, Canada.

The fate of mercury (Hg) released from dental "silver" amalgam tooth fillings into human mouth air is uncertain. A previous report about sheep revealed uptake routes and distribution of amalgam Hg among body tissues. The present investigation demonstrates the bodily distribution of amalgam Hg in a monkey whose dentition, diet, feeding regimen, and chewing pattern closely resemble those of humans. When amalgam fillings, which normally contain 50% Hg, are made with a tracer of radioactive 203Hg and then placed into monkey teeth, the isotope appears in high concentration in various organs and tissues within 4 wk. Whole-body images of the monkey revealed that the highest levels of Hg were located in the kidney, gastrointestinal tract, and jaw. The dental profession's advocacy of silver amalgam as a stable tooth restorative material is not supported by these findings.
Antimicrob Agents Chemother 1993 Apr;37(4):825-34 Related Articles, Links


Comment in:
Antimicrob Agents Chemother. 1993 Aug;37(8):1730-1.

Mercury released from dental "silver" fillings provokes an increase in mercury- and antibiotic-resistant bacteria in oral and intestinal floras of primates.

Summers AO, Wireman J, Vimy MJ, Lorscheider FL, Marshall B, Levy SB, Bennett S, Billard L.

Department of Microbiology, University of Georgia, Athens 30602.

In a survey of 640 human subjects, a subgroup of 356 persons without recent exposure to antibiotics demonstrated that those with a high prevalence of Hg resistance in their intestinal floras were significantly more likely to also have resistance to two or more antibiotics. This observation led us to consider the possibility that mercury released from amalgam ("silver") dental restorations might be a selective agent for both mercury- and antibiotic-resistant bacteria in the oral and intestinal floras of primates. Resistances to mercury and to several antibiotics were examined in the oral and intestinal floras of six adult monkeys prior to the installation of amalgam fillings, during the time they were in place, and after replacement of the amalgam fillings with glass ionomer fillings (in four of the monkeys). The monkeys were fed an antibiotic-free diet, and fecal mercury concentrations were monitored. There was a statistically significant increase in the incidence of mercury-resistant bacteria during the 5 weeks following installation of the amalgam fillings and during the 5 weeks immediately following their replacement with glass ionomer fillings. These peaks in incidence of mercury-resistant bacteria correlated with peaks of Hg elimination (as high as 1 mM in the feces) immediately following amalgam placement and immediately after replacement of the amalgam fillings. Representative mercury-resistant isolates of three selected bacterial families (oral streptococci, members of the family Enterobacteriaceae, and enterococci) were also resistant to one or more antibiotics, including ampicillin, tetracycline, streptomycin, kanamycin, and chloramphenicol. While such mercury- and antibiotic-resistant isolates among the staphylococci, the enterococci, and members of the family Enterobacteriaceae have been described, this is the first report of mercury resistance in the oral streptococci. Many of the enterobacterial strains were able to transfer mercury and antibiotic resistances together to laboratory bacterial recipients, suggesting that the loci for these resistances are genetically linked. Our findings indicate that mercury released from amalgam fillings can cause an enrichment of mercury resistance plasmids in the normal bacterial floras of primates. Many of these plasmids also carry antibiotic resistance, implicating the exposure to mercury from dental amalgams in an increased incidence of multiple antibiotic resistance plasmids in the normal floras of nonmedicated subjects.

J Dent Res 1998 Jun;77(6):1415-25 Related Articles, Links


Activation of the immune system and systemic immune-complex deposits in Brown Norway rats with dental amalgam restorations.

Hultman P, Lindh U, Horsted-Bindslev P.

Department of Health and Environment, Linkoping University, Sweden.

Dental amalgam restorations are a significant source of mercury exposure in the human population, but their potential to cause systemic health effects is highly disputed. We examined effects on the immune system by giving genetically mercury-susceptible Brown Norway (BN) rats and mercury-resistant Lewis (LE) rats silver amalgam restorations in 4 molars of the upper jaw, causing a body burden similar to that described in human amalgam-bearers (from 250 to 375 mg amalgam/kg body weight). BN rats with amalgam restorations, compared with control rats given composite resinous restorations, developed a rapid activation of the immune system, with a maximum 12-fold increase of the plasma IgE concentration after 3 wks (p < 0.001; Mann-Whitney's test). LE rats receiving amalgam restorations showed no significant increase of plasma IgE (p > 0.05). After 12 wks, BN rats with amalgam restorations showed significantly increased (p < 0.05) titers of immune-complex (IC) deposits in the renal glomeruli and in the vessel walls of internal organs. These rats also showed a significant (p < 0.05), from six- to 130-fold, increase in tissue mercury concentration in the concentration order kidney > spleen > cerebrum occipital lobe > cerebellum > liver > thymus, and the tissue silver concentration was significantly (p < 0.05) increased from three- to 11-fold. Amalgam-implanted BN rats showed a significant (p < 0.05) increase in copper concentration in the kidney and spleen, and in kidney selenium concentration. We conclude that dental amalgam restorations release substantial amounts of their elements, which accumulate in the organs and which, in genetically susceptible rats, give rise to activation of the immune system and systemic IC deposits.

Scand J Dent Res 1983 Apr;91(2):150-2 Related Articles, Links


Methylation of mercury from dental amalgam and mercuric chloride by oral streptococci in vitro.

Heintze U, Edwardsson S, Derand T, Birkhed D.

The capacity of the oral bacteria Streptococcus mitior, S. mutans and S. sanguis to methylate mercury was investigated in vitro. Mercuric chloride and pulverized dental amalgam in distilled water, respectively, were used as sources of mercury. Methylmercury was found in the bacterial cells of all three tested strains. The results indicate that organic mercury compounds may be formed in the oral cavity.

 

Re: Dental mercury is a real threat (long) » Larry Hoover

Posted by JrBecker on May 3, 2003, at 13:32:23

In reply to Re: Dental mercury is a real threat (long), posted by Larry Hoover on May 3, 2003, at 12:36:56

Larry, quite fascinating. Does a general dentist typically screen for high levels of mercury if requested? And would these tests actually tell something useful? In other words, is there some sort of standard measure of mercury levels that would warrant action? Or is it really much more hit or miss than that and the only way to see if the fillings have an effect is to actually remove them? Would like to know since I have a few myself.

Let us know if you have any instinct on this when you get back midweek. Thanks.

JB

 

Re: Dental mercury is a real threat (long) » JrBecker

Posted by leeran on May 3, 2003, at 13:57:00

In reply to Re: Dental mercury is a real threat (long) » Larry Hoover, posted by JrBecker on May 3, 2003, at 13:32:23

Hi there,

I don't mean to butt in (and I certainly don't want to cause a larger brouhaha then I already have by answering the first post), but I found this website with a page of links to mercury testing sources just the other day when I was researching all of this.

http://www.testfoundation.org/hglabs.htm

To be perfectly honest, I'm rather paranoid (to use MattDDS's word :-) about having these two (of many) amalgam fillings drilled out this Thursday. I didn't think to quiz the dentist about the precautions he uses during the drilling/removal process when I met with him last week. I'm particularly concerned about the inhalation hazard.

Back to the website link I posted - I feel relatively comfortable with the links on the aforementioned website because this site is organized by a (supposed) non-profit group that doesn't sell/market any services of their own (formed by the Dr. Boyd Haley, Ph.D. Biochemist, Professor and Chair of Chemistry Department, University of Kentucky).


 

Re: Dental amalgam, again » mattdds

Posted by stjames on May 4, 2003, at 15:12:13

In reply to Dental amalgam, again » leeran, posted by mattdds on May 1, 2003, at 21:05:46

Clearly mercury is toxic, but here is my quandry.
I have way over 100 amalgam fillings, top and bottom, past the canines. It is common in my fathers family to
have large #'s of cavities till about 18 and then have almost none. This despite excellent dental care (floride by pill, mouthwash and twice a year office treatments (while still a kid), good brushing, and limiting of foods that cause cavities). From the canines to the front epoxy
was used for the fillings,
(whatever composite that required a light source
to cure, in the 1970's-80). The front fillings have fallen out a few times, but the back only once, in 30 years. I have no crowns or anythng else, just fillings.

So it would seem removing this much amalgam would
render a huge dose of mercury into my body & the cost of this much gold makes this even more not an option. Not to mention the cost of removal and loss of even more tooth material. Comments, please.

With hind sight, what would of been a better option for a kid who has 6 cavities every 6 months, for over 10 years ? Gold seems too expensive on this scale. I suspect Epoxy would
fall out, for me, if used on the back teeth.

 

Re: Dental mercury is a real threat (long)

Posted by stjames on May 4, 2003, at 15:19:15

In reply to Re: Dental mercury is a real threat (long), posted by Larry Hoover on May 3, 2003, at 12:36:56

> About Quackwatch: Dr. Barrett, the dude who runs the site, has been successfully sued for providing biased and defamatory information. Take him with a grain of salt. He generally ignores any science that doesn't fit with his preconceived notions. That's not to say that he's always wrong, but he is often so.


So if the courts say it is not good science or heath, that's it ? All this tells me is the Qwacks have good lawyers and Qwackery is big business. Barrett is a zellot, but you, Larry
as a man of science (at least that is the role
you play here) quoting law and making it science
fact has given me pause to disgreguard your posts.

 

Thanks Larry! How much do I owe you? :-) (nm)

Posted by David Smith on May 4, 2003, at 22:31:22

In reply to Re: Dental mercury is a real threat (long), posted by Larry Hoover on May 3, 2003, at 12:36:56

 

Dental amalgam increases disease? Or just Hg level » Larry Hoover

Posted by mattdds on May 5, 2003, at 14:10:04

In reply to Re: Dental mercury is a real threat (long), posted by Larry Hoover on May 3, 2003, at 12:36:56

Larry,

You certainly seem to have done your homework on this, and I am overwhelmed by the amount of citations you have provided.

I briefly looked through them, and although the recurrent theme is that mercury is that mercury is indeed a neurotoxin, and definitely an environmental problem as far as disposal, I still am not convinced that there is any correlation between dental amalgams and actual disease. Do you know of any such convincing evidence? I am not aware of any. I don't mean evidence showing how much mercury is liberated during mastication, I mean actual epidemiological evidence linking, e.g. depression to the amount of restored tooth surfaces in amalgam.

Don't you think this would simplify things a bit? Because until we have real epidemiological evidence linking amalgam fillings to real diagnosable diseases, we are making rather large inductive leaps that cannot be considered good science. So all the discussion about mercury levels liberated during mastication, etc. seems like somewhat of a waste of time, when we could just cut to the chase and ask "does mercury used in a dental setting cause an increase in systemic diseases, or psychiatric problems?". As of now I think the answer is an unequivocal "NO, it does not".

Meanwhile, we have a real, tangible disease to be dealt with: dental caries. And we have to make decisions about how to treat it. Dental amalgam, for many years was THE only option in the armamentarium to treat dental caries, and it remains one of the best for it's strength and affordability. I mean, we can't just go extracting everyone's teeth, just because of what dental amalgam MIGHT do. So we have to make decisions, and to most dentists and people, this was the best one! There is no perfect restorative material, otherwise we would be using it, and avoiding amalgam altogether.

I was a bit put off by something you said:

>> Think about the brilliance of the first dentist who used it: "Duh! I know! Let's store mercury in people's mouths, and we'll tell them it's safe."

Do you really believe this was some evil plot by a dentist to get rid of mercury in the environment? Strange, I figured it was probably just some dentist trying to fix a tooth, rather than some elaborate evil scheme to poison everyone. Occams Razor comes to mind here. Which would be the simpler explanation? I was a bit surprised that you would say this, being the scientifically minded and intelligent person you seem to be. (Most) dentists are just doing their job of trying to restore function in peoples mouths and prevent further disease (with which dental amalgam has unquestionably helped). Saying this seems somewhat irresponsible to me, because people here value your opinions, and they might draw conclusions based on what you say (perhaps making them want to avoid the dentist altogether).

I am not married to any of the ideas promoted by the ADA, WHO or AMA, but I do feel that whoever makes the claim that dental amalgam is causing depression, multiple sclerosis, etc. bears a tremendous amount of burden to provide evidence for this. The ADA had nothing to gain from their numerous studies on amalgam (all of which failed to show associations between systemic disease and amalgam fillings).

I see using dental amalgam in dentistry somewhat akin to using Lithium or SSRI's in psychiatry. Although we whine that there is no perfect "silver" bullet in psychiatry, we use the best tools that we have, and we make calculated risk to benefit analyses. There are very tangible risks of using some psychiatric drugs, like the MAOI's, TCA's, benzos, and mood stabilizers. But we feel the benefits outweigh the risks. This is the same thing with dental amalgam, but I feel the risks are even smaller and the benefits are great.

Am I making sense here?

Respectfully,

Matt

 

Re: Dental mercury is a real threat » leeran

Posted by David Smith on May 5, 2003, at 22:20:52

In reply to Re: Dental mercury is a real threat (long) » JrBecker, posted by leeran on May 3, 2003, at 13:57:00

Thank you for the link JR.
That is a fascinating website. It seems unbiased,
with pros and cons on both sides. From what I
have read the biggest risks for amalgam removal
are associated with heart patients. Perhaps you
might discuss your concerns with your dentist.
I freak out whenever I am in "the chair."
Fortunately my dentist is able to alleviate my fears.
I hope you post a followup to let us know
how you are doing. GOODLUCK!!!

 

Re: Dental mercury is a real threat » David Smith

Posted by leeran on May 5, 2003, at 23:56:52

In reply to Re: Dental mercury is a real threat » leeran, posted by David Smith on May 5, 2003, at 22:20:52

Thanks, David Smith, for your well wishes.

I have a myocardial infarction, so I need to remember to take antibiotics before I go . . . not that I think the antibiotics would help with anything that's mercury/heart related.

One way or another, this filling will have to come out because of the broken tooth. I'll be so relieved when it's over . . .

Thanks again, and I'll post a follow-up.

 

Re: Dental amalgam, again Attn mattdds

Posted by stjames on May 6, 2003, at 13:46:09

In reply to Re: Dental amalgam, again » mattdds, posted by stjames on May 4, 2003, at 15:12:13

Clearly mercury is toxic, but here is my quandry.
I have way over 100 amalgam fillings, top and bottom, past the canines. It is common in my fathers family to
have large #'s of cavities till about 18 and then have almost none. This despite excellent dental care (floride by pill, mouthwash and twice a year office treatments (while still a kid), good brushing, and limiting of foods that cause cavities). From the canines to the front epoxy
was used for the fillings,
(whatever composite that required a light source
to cure, in the 1970's-80). The front fillings have fallen out a few times, but the back only once, in 30 years. I have no crowns or anythng else, just fillings.

So it would seem removing this much amalgam would
render a huge dose of mercury into my body & the cost of this much gold makes this even more not an option. Not to mention the cost of removal and loss of even more tooth material. Comments, please.

With hind sight, what would of been a better option for a kid who has 6 cavities every 6 months, for over 10 years ? Gold seems too expensive on this scale. I suspect Epoxy would
fall out, for me, if used on the back teeth.

 

Re: Dental amalgam increases disease? (long) » mattdds

Posted by Larry Hoover on May 8, 2003, at 9:57:19

In reply to Dental amalgam increases disease? Or just Hg level » Larry Hoover, posted by mattdds on May 5, 2003, at 14:10:04

> Larry,
>
> You certainly seem to have done your homework on this, and I am overwhelmed by the amount of citations you have provided.
>
> I briefly looked through them, and although the recurrent theme is that mercury is that mercury is indeed a neurotoxin, and definitely an environmental problem as far as disposal, I still am not convinced that there is any correlation between dental amalgams and actual disease. Do you know of any such convincing evidence? I am not aware of any. I don't mean evidence showing how much mercury is liberated during mastication, I mean actual epidemiological evidence linking, e.g. depression to the amount of restored tooth surfaces in amalgam.
>
> Don't you think this would simplify things a bit? Because until we have real epidemiological evidence linking amalgam fillings to real diagnosable diseases, we are making rather large inductive leaps that cannot be considered good science. So all the discussion about mercury levels liberated during mastication, etc. seems like somewhat of a waste of time, when we could just cut to the chase and ask "does mercury used in a dental setting cause an increase in systemic diseases, or psychiatric problems?". As of now I think the answer is an unequivocal "NO, it does not".

The problem is that the correlation between these two parameters has been little studied. It is an axiom in science, "The absence of evidence is not evidence of absence." There have been some reasonably large epidemiological reports finding no relationship, but in some studies within preselected populations, there have been correlations. Here are a few abstracts that are suggestive of physical, psychological and behavioural impacts directly linked to amalgam, or similar exposures:

J Nephrol 2002 Mar-Apr;15(2):171-6

Mercury in dental restoration: is there a risk of nephrotoxicity?

Mortada WL, Sobh MA, El-Defrawy MM, Farahat SE.

Urology and Nephrology Center, Mansoura University, Faculty of Science, Egypt.

BACKGROUND: Concern has been voiced about exposure to mercury (Hg) from dental amalgam fillings, and there is a need to assess whether this leads to signs of nephrotoxicity. METHODS: A total of 101 healthy adults (80 males and 21 females) were included in this study. The population as grouped into those having amalgam fillings (39 males and 10 females) and those without (41 males and 11 females). Hg was determined in blood, urine, hair and nails to assess exposure. Urinary excretion of beta2-microglobulin (beta2M), N-acetyl-beta-D-glucosaminidase (NAG), gamma-glutamyltransferase (gammaGT) and alkaline phosphatase (ALP) were determined as markers of tubular damage. Albuminuria was assayed as an early indicator of glomerular dysfunction. Serum creatinine, beta2M and blood urea nitrogen (BUN) were determined to assess glomerular filtration. RESULTS: Hg levels in blood and urine were significantly higher in persons with dental amalgam than those without; in the dental amalgam group, blood and urine levels of Hg significantly correlated with the number of amalgams. Urinary excretion of NAG, gammaGT and albumin was significantly higher in persons with dental amalgam than those without. In the amalgam group, urinary excretion of NAG and albumin significantly correlated with the number of fillings. Albuminuria significantly correlated with blood and urine Hg. CONCLUSION: From the nephrotoxicity point of view, dental amalgam is an unsuitable filling material, as it may give rise to Hg toxicity. Hg levels in blood and urine are good markers of such toxicity. In these exposure conditions, renal damage is possible and may be assessed by urinary excretions of albumin, NAG, and gamma-GT.


Sci Total Environ 1990 Dec 1;99(1-2):23-35

The relationship between mercury from dental amalgam and the cardiovascular system.

Siblerud RL.

Department of Physiology, College of Veterinary Medicine and Biological Sciences, Colorado State University, Fort Collins 80523.

The findings presented here suggest that mercury poisoning from dental amalgam may play a role in the etiology of cardiovascular disorders. Comparisons between subjects with and without amalgam showed amalgam-bearing subjects had significantly higher blood pressure, lower heart rate, lower hemoglobin, and lower hematocrit. Hemoglobin, hematocrit, and red blood cells were significantly lower when correlated to increased levels of urine mercury. The amalgam subjects had a greater incidence of chest pains, tachycardia, anemia, fatigue, tiring easily, and being tired in the morning. The data suggest that inorganic mercury poisoning from dental amalgam does affect the cardiovascular system.

Am J Psychother 1989 Oct;43(4):575-87

The relationship between mercury from dental amalgam and mental health.

Siblerud RL.

Colorado State University, Department of Physiology, Fort Collins.

The findings presented here suggest that mercury poisoning from dental amalgam may play a role in the etiology of mental illness. Comparisons between subjects with and without amalgam showed significant differences in subjective reports of mental health. Subjects who had amalgams removed reported that symptoms of mental illness lessened or disappeared after removal. The data suggest that inorganic mercury poisoning from dental amalgam does affect the mind and emotions.

Psychol Rep 1994 Feb;74(1):67-80

Psychometric evidence that mercury from silver dental fillings may be an etiological factor in depression, excessive anger, and anxiety.

Siblerud RL, Motl J, Kienholz E.

Rocky Mountain Research Institute, Inc., Fort Collins, CO 80524.

Scores on the Beck Depression Inventory were compared for 25 women who had silver dental fillings (amalgams) and for 23 women without amalgams. Women with amalgams had significantly higher scores and reported more symptoms of fatigue and insomnia. Anger scores from the State-Trait Anger Expression Inventory showed that the women with amalgams had statistically significantly higher mean scores on expressing anger without provocation and experiencing more intense angry feelings. The women without amalgams scored significantly higher on controlling anger, which suggested they invested more energy in monitoring and preventing the experience and expression of anger. Anxiety scores from the State-Trait Anxiety Inventory showed the women with amalgams scored significantly less pleasant, satisfied, happy, secure, and steady, and had a more difficult time making decisions. They had significantly higher Trait Anxiety scores. The women with amalgams also had significantly higher levels of mercury in the oral cavity before and after chewing gum. The study suggests that amalgam mercury may be an etiological factor in depression, excessive anger, and anxiety because mercury can produce such symptoms perhaps by affecting the neurotransmitters in the brain.

Psychol Rep 1992 Jun;70(3 Pt 2):1139-51

A comparison of mental health of multiple sclerosis patients with silver/mercury dental fillings and those with fillings removed.

Siblerud RL.

Rocky Mountain Research Institute, Inc., Colorado.

In this study was compared the mental health status of 47 multiple sclerosis patients with silver/mercury tooth fillings (amalgams) to that of 50 patients with their fillings removed. On the Beck Depression Inventory the multiple sclerosis subjects with amalgams suffered significantly more depression while their scores on the State-Trait Anger Expression Inventory indicated the former group also exhibited significantly more anger. On the SCL-90 Revised, subjects with amalgam fillings had significantly more symptoms of depression, hostility, psychotism, and were more obsessive-compulsive than the patients with such fillings removed. On a questionnaire containing 18 mental health symptoms multiple sclerosis subjects with amalgam fillings reported a history of 43% more symptoms than those without amalgam fillings over the past 12 months. These data suggested that the poorer mental health status exhibited by multiple sclerosis subjects with dental amalgam fillings may be associated with mercury toxicity from the amalgam.

FASEB J 1998 Aug;12(11):971-80

Neurobehavioral effects from exposure to dental amalgam Hg(o): new distinctions between recent exposure and Hg body burden.

Echeverria D, Aposhian HV, Woods JS, Heyer NJ, Aposhian MM, Bittner AC Jr, Mahurin RK, Cianciola M.

Battelle Centers for Public Health Research and Evaluation, Seattle, Washington 98105, USA.

Potential toxicity from exposure to mercury vapor (Hg(o)) from dental amalgam fillings is the subject of current public health debate in many countries. We evaluated potential central nervous system (CNS) toxicity associated with handling Hg-containing amalgam materials among dental personnel with very low levels of Hg(o) exposure (i.e., urinary Hg <4 microg/l), applying a neurobehavioral test battery to evaluate CNS functions in relation to both recent exposure and Hg body burden. New distinctions between subtle preclinical effects on symptoms, mood, motor function, and cognition were found associated with Hg body burden as compared with those associated with recent exposure. The pattern of results, comparable to findings previously reported among subjects with urinary Hg >50 microg/l, presents convincing new evidence of adverse behavioral effects associated with low Hg(o) exposures within the range of that received by the general population.

Neurotoxicol Teratol 1995 Mar-Apr;17(2):161-8

Behavioral effects of low-level exposure to elemental Hg among dentists.

Echeverria D, Heyer NJ, Martin MD, Naleway CA, Woods JS, Bittner AC Jr.

Battelle Center for Public Health Research and Evaluation (CPHRE), Seattle, WA 98105, USA.

Exposure thresholds for health effects associated with elemental mercury (Hg degree) exposure were examined by comparing behavioral test scores of 19 exposed (mean urinary Hg = 36 micrograms/l) with those of 20 unexposed dentists. Thirty-six micrograms Hg/l is 7 times greater than the 5 micrograms Hg/l mean level measured in a national sample of dentists. To improve the distinction between recent and cumulative effects, the study also evaluated porphyrin concentrations in urine, which are correlated with renal Hg content (a measure of cumulative body burden). Subjects provided an on-site spot urine sample, were administered a 1-h assessment consisting of a consent form, the Profile of Mood Scales, a symptom and medical questionnaire, and 6 behavioral tests: digit-span, symbol-digit substitution, simple reaction time, the ability to switch between tasks, vocabulary, and the One Hole Test. Multivariate regression techniques were used to evaluate dose-effects controlling for the effects of age, race, gender and alcohol consumption. A dose-effect was considered statistically significant below a p value of 0.05. Significant urinary Hg dose-effects were found for poor mental concentration, emotional lability, somatosensory irritation, and mood scores. Individual tests evaluating cognitive and motor function changed in the expected directions but were not significantly associated with urinary Hg. However, the pooled sum of rank scores for combinations of tests within domains were significantly associated with urinary Hg, providing evidence of subtle preclinical changes in behavior associated with Hg exposure. Coproporphyrin, one of three urinary porphyrins altered by mercury exposure, was significantly associated with deficits in digit span and simple reaction time.


> Meanwhile, we have a real, tangible disease to be dealt with: dental caries. And we have to make decisions about how to treat it. Dental amalgam, for many years was THE only option in the armamentarium to treat dental caries, and it remains one of the best for it's strength and affordability. I mean, we can't just go extracting everyone's teeth, just because of what dental amalgam MIGHT do. So we have to make decisions, and to most dentists and people, this was the best one! There is no perfect restorative material, otherwise we would be using it, and avoiding amalgam altogether.

That begs the question, "Why avoid it, if it causes no harm?" You see, the question is framed in the dental community as one of risk-benefit analysis rather than one of simply assessing the risk. What is becoming clear is that the mercury in amalgam is quite labile in some cases. The quality of an amalgam restoration can only approach theoretical minimal release, but there are a variety of factors which can cause much higher releases. Every time you breathe or swallow, if you have amalgam in your mouth, you are being exposed to mercury. Some people are exquisitely sensitive to mercury, so the idea that there is a safe level of exposure based on population statistics has no bearing on their experience. Consider the following:

Toxicol Lett 1996 Feb;84(2):113-22

Comment in:
Toxicol Lett. 1998 Sep 1;98(1-2):123-7.

Psychological and somatic subjective symptoms as a result of dermatological patch testing with metallic mercury and phenyl mercuric acetate.

Marcusson JA.

Department of Dermatology, Huddinge University Hospital, Sweden.

Sixty patients with a history of malaise over the ensuing weeks following the drilling out of old amalgam fillings were included in the study. They were tested epicutaneously weekly (standard procedure) with either 0.5% metallic mercury in petrolatum or 0.01% phenyl mercuric acetate in water, and, on 2 separate occasions, with only saline or petrolatum as a control according to a randomized double-blind protocol. The presence or absence of an allergic patch test response was read on day 3. Two patients showed allergic cutaneous responses towards metallic mercury and 1 to phenyl mercuric acetate. There was a concurrent 7-day self-registration of subjective psychological and somatic symptoms, using a validated visual analogue scale (minor symptom evaluation profile; MSE). In the group analysis it was clearly shown that the patients reacted with subjective symptoms to phenyl mercuric acetate. A reaction to test doses of metallic mercury seems to exist but could only be visualized when a scoring system was elaborated to individually define those subjects with a psychological and somatic response to test doses of mercury. This psychosomatic reactivity, named intolerance, seems to be unrelated to the cutaneous delayed allergic skin response. Thus, it might be possible to identify patients intolerant to small test doses of percutaneously penetrating mercury (previously considered innocuous). These findings may have a bearing on the systemic side-effects attributed to mercury released from amalgam tooth fillings.

Now, the idea that there is a disorder of defined characteristics arising from exposure to mercury in amalgam, sometimes called "amalgam disease", has received some fairly intensive study. Not surprisingly (as I'll explain), most of the results have been negative, instead attributing the complaints of the subjects as somatization, i.e. of psychological rather than physical origin. The problem with this is that the very nature of the issue, that a commonly-experienced low-level exposure to a proven neurotoxin is almost certainly bound to attract the attention of those people who are somatizers. If you allow those people to self-select into the study population, you no longer have a representative population sample. Those with mercury sensitivities will surely be diluted to such an extent that no relationship will be found. Instead, consider the possibility that those with mercury sensitivity have been given reasonable alternative explanations for their symptomatology, such as dysthymia, depression, or chronic fatigue. They already have a plausible explanation, so may no longer seek out alternative viewpoints. I think it is reasonable to consider mercury exposure as a possible factor influencing mood disorders. Perhaps subtle, perhaps profound.

In some places in the world, amalgam disease is taken seriously.

Neuroendocrinol Lett 2002 Oct-Dec;23(5-6):459-82

Removal of dental amalgam and other metal alloys supported by antioxidant therapy alleviates symptoms and improves quality of life in patients with amalgam-associated ill health.

Lindh U, Hudecek R, Danersund A, Eriksson S, Lindvall A.

Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, SE-751 85 Uppsala, Sweden. Ulf.Lindh@bms.uu.se

OBJECTIVES: The purpose of this study was to evaluate treatment of patients suffering from chronic ill health with a multitude of symptoms associated with metal exposure from dental amalgam and other metal alloys. SETTING AND DESIGN: We included 796 patients in a retrospective study using a questionnaire about symptom changes, changes in quality of life as a consequence of treatment and assessment of care taking. METHODS: Treatment of the patients by removal of offending dental metals and concomitant antioxidant therapy was implemented according to the Uppsala model based on a close co-operation between physicians and dentists. RESULTS: More than 70% of the responders, remaining after exclusion of those who had not begun or completed removal, reported substantial recovery and increased quality of life. Comparison with similar studies showed accordance of the main results. Plasma concentrations of mercury before and after treatment supported the metal exposure to be causative for the ill health. MAIN FINDINGS: Treatment according to the Uppsala model proved to be adequate for more than 70% of the patients. Patients with a high probability to respond successfully to current therapy might be detected by symptom profiles before treatment. CONCLUSIONS: The hypothesis that metal exposure from dental amalgam can cause ill health in a susceptible part of the exposed population was supported. Further research is warranted to develop laboratory tests to support identification of the group of patients responding to current therapy as well as to find out causes of problems in the group with no or negative results.

Moreover, it is entirely possible that the doctors have been looking in the wrong place all along. Mercury can form irreversible covalent bonds with selenium, which is both good and bad. It takes organic mercury out of the picture, but at the price of an esssential trace mineral. Consider:

Environ Res 2001 Dec;87(3):141-6

Dental amalgam and selenium in blood.

Hol PJ, Vamnes JS, Gjerdet NR, Eide R, Isrenn R.

Department of Odontology-Dental Biomaterials, University of Bergen, Aarstadveien 17, Bergen, N-5009, Norway.

It has been suggested that selenium (Se) exhibits protective effects against mercury (Hg) toxicity in humans due to formation of a Hg-Se complex bound to selenoprotein P in blood. The aim of the present study was to investigate Se concentrations in persons who had been examined with respect to general health problems associated with dental amalgam fillings. The Se concentrations were determined in whole-blood samples of 80 individuals by hydride generation atomic absorption spectrometry. The subjects comprised two main groups: 21 healthy controls with amalgam fillings and 20 patients who claimed symptoms from existing amalgam fillings. The median concentration of Se in blood (119.2 microg/L) was statistically significantly lower in subjects who claimed symptoms of mercury amalgam illness than in healthy subjects with amalgam (130.3 microg/L). The difference was more evident in individuals with more than 35 amalgam surfaces (P=0.003). Additional control groups without amalgam fillings comprised 19 healthy controls without amalgam experience and 20 subjects who have had amalgam fillings removed due to suspected symptoms associated with amalgam. The Se concentrations in these groups were not different from those with amalgam. It is indicated that persons with ill health self-related to dental amalgam might have a Se metabolism different from that of healthy people.

One of the reasons mercury is toxic is that it disrupts sulphur-bearing molecules, including many enzymes which rely on sulphur-linkages for their three-dimensional structure (and thus their functionality). Just look around this board and see how many people are dealing with sulphur-amino acid issues: S-adenosyl methionine (SAMe), methionine, betaine (indirectly), folate and B-12 supplements (indirectly), homocysteine. Consider the number of people taking supplemental sulphur in the form of MSM (methyl sulphonyl methane) for e.g. joint problems, or dimethyl sulphoxide (DMSO). People consider taking taurine (sulphur-bearing), and I'm forgetting many other examples right now (I'm still foggy from my trip). The point is, I have seen no research linking mercury exposure to disordered sulphur metabolism, but I have seen massive correlation between sulphur metabolism and depression. Stay tuned.

> I was a bit put off by something you said:
>
> >> Think about the brilliance of the first dentist who used it: "Duh! I know! Let's store mercury in people's mouths, and we'll tell them it's safe."
>
> Do you really believe this was some evil plot by a dentist to get rid of mercury in the environment?

Were I to rewrite that phrase today, I would use "place" instead of "store". I did not mean to suggest environmental concerns in any respect. You're a dentist, right? It just hit me that you are mattdds. You have very exacting protocols on what to do with excess amalgam, right? You wear rubber gloves to protect against even trivial dermal exposure, correct? But you have no problem placing an amalgam on a buccal surface, guaranteeing exposure to cheek skin, right? Or on an occlusal surface, even in bruxists? Doesn't this seem to suggest different standards being applied in these two situations?

>Strange, I figured it was probably just some dentist trying to fix a tooth, rather than some elaborate evil scheme to poison everyone. Occams Razor comes to mind here. Which would be the simpler explanation? I was a bit surprised that you would say this, being the scientifically minded and intelligent person you seem to be. (Most) dentists are just doing their job of trying to restore function in peoples mouths and prevent further disease (with which dental amalgam has unquestionably helped).

I apologize for offending you, but not for making my statement. I have been told that I can be over-the-top in my negative characterizations, but I do believe that my personal feelings came across, non?

Dentists, like any well-schooled people, are indoctrinated to believe what the extablishment has disseminated. Most of the time, that is an admirable and responsible process, guaranteeing a standard of care across the board. In some cases, it flies in the face of the evidence.

Consider the general concept known as GRAS (Generally Recognized As Safe). Basically, it "grandfathers" well-established practices, and exempts them from focussed inquiry into adverse affects of their use. I would ask you this: "If mercury amalgams were being proposed today as an innovative restorative material for dental caries, do you think that they would get past the regulatory approval process in existence today?" I can guarantee you, they would not get past the committee stage, let alone get into animal trials.

>Saying this seems somewhat irresponsible to me, because people here value your opinions, and they might draw conclusions based on what you say (perhaps making them want to avoid the dentist altogether).

I would hate to think that my statement would have that effect.

I am a human being, full of opinions, all of which are unabashedly biased. Just for the record, I ascribe to an AA aphorism, "Opinions are like assholes. Everybody's got one, and they all stink."

> I am not married to any of the ideas promoted by the ADA, WHO or AMA, but I do feel that whoever makes the claim that dental amalgam is causing depression, multiple sclerosis, etc. bears a tremendous amount of burden to provide evidence for this. The ADA had nothing to gain from their numerous studies on amalgam (all of which failed to show associations between systemic disease and amalgam fillings).

I must declare that I categorically oppose that viewpoint. Given the proclivity of the American culture to sue (that was not intended to slight Americans, but I don't think anyone would really deny that), do you really think that the dental establishment has nothing to gain?

> I see using dental amalgam in dentistry somewhat akin to using Lithium or SSRI's in psychiatry. Although we whine that there is no perfect "silver" bullet in psychiatry, we use the best tools that we have, and we make calculated risk to benefit analyses. There are very tangible risks of using some psychiatric drugs, like the MAOI's, TCA's, benzos, and mood stabilizers. But we feel the benefits outweigh the risks. This is the same thing with dental amalgam, but I feel the risks are even smaller and the benefits are great.
>
> Am I making sense here?
>
> Respectfully,
>
> Matt

Respect returned.

Lar

Random extras:

Toxicology 1995 Mar 31;97(1-3):19-22

The dental amalgam mercury controversy--inorganic mercury and the CNS; genetic linkage of mercury and antibiotic resistances in intestinal bacteria.

Lorscheider FL, Vimy MJ, Summers AO, Zwiers H.

Department of Medical Physiology, Faculty of Medicine, University of Calgary, Alberta, Canada.

Mercury (Hg) vapor exposure from dental amalgam has been demonstrated to exceed the sum of all other exposure sources. Therefore the effects of inorganic Hg exposure upon cell function in the brain and in the intestinal bacteria have recently been examined. In rats we demonstrate that ADP-ribosylation of tubulin and actin brain proteins is markedly inhibited, and that ionic Hg can thus alter a neurochemical reaction involved with maintaining neuron membrane structure. In monkeys we show that Hg, specifically from amalgam, will enrich the intestinal flora with Hg-resistant bacterial species which in turn also become resistant to antibiotics.

Biometals 1999 Sep;12(3):227-31

Dental amalgam mercury exposure in rats.

Galic N, Prpic-Mehicic G, Prester L, Blanusa M, Krnic Z, Ferencic Z.

Department of Dental Pathology, School of Dentistry, Zagreb, Croatia.

The aim of this study was to measure the distribution of mercury, in tissues of rats exposed to amalgam over a two months period. Possible interaction of mercury with copper and zinc in organs was also evaluated. Rats were either exposed to mercury from 4 dental amalgams, or fed the diet containing powdered amalgam during two months. Mercury was measured in the kidney, liver and brain, copper in kidney and brain and zinc in kidney. The results showed significantly higher concentrations of mercury in the kidneys and the brains of rats in both exposed groups compared to control. Even after two months of exposure to mercury brain mercury concentration in rats with amalgam fillings was 8 times higher than in the control and 2 times higher than in rats exposed to amalgam supplemented diet. The highest mercury concentration in the latter group was found in the kidneys and it was 5 times higher than in the control group. We found no significant differences between mercury levels in exposed and control rat's liver. Exposure to mercury from dental amalgams did not alter the concentrations of copper and zinc in the tissues. Histopathological analyses of rats tissues did not show any pathological changes. These results support previously proposed nose-brain transport of mercury released from dental amalgam fillings.

Biol Trace Elem Res 1997 Feb;56(2):143-52

Mercury from maternal "silver" tooth fillings in sheep and human breast milk. A source of neonatal exposure.

Vimy MJ, Hooper DE, King WW, Lorscheider FL.

Department of Medicine, Faculty of Medicine, University of Calgary, Alberta, Canada.

Neonatal uptake of mercury (Hg) from milk was examined in a pregnant sheep model, where radioactive mercury (Hg203)/silver tooth fillings (amalgam) were newly placed. A crossover experimental design was used in which lactating ewes nursed foster lambs. In a parallel study, the relationship between dental history and breast milk concentration of Hg was also examined in 33 lactating women. Results from the animal studies showed that, during pregnancy, a primary fetal site of amalgam Hg concentration is the liver, and, after delivery, the neonatal lamb kidney receives additional amalgam Hg from mother's milk. In lactating women with aged amalgam fillings, increased Hg excretion in breast milk and urine correlated with the number of fillings or Hg vapor concentration levels in mouth air. It was concluded that Hg originating from maternal amalgam tooth fillings transfers across the placenta to the fetus, across the mammary gland into milk ingested by the newborn, and ultimately into neonatal body tissues. Comparisons are made to the U. S. minimal risk level recently established for adult Hg exposure. These findings suggest that placement and removal of "silver" tooth fillings in pregnant and lactating humans will subject the fetus and neonate to unnecessary risk of Hg exposure.

FASEB J 1990 Nov;4(14):3256-60

Comment in:
FASEB J. 1991 Feb;5(2):236.

Whole-body imaging of the distribution of mercury released from dental fillings into monkey tissues.

Hahn LJ, Kloiber R, Leininger RW, Vimy MJ, Lorscheider FL.

Department of Radiology, University of Calgary, Faculty of Medicine, Alberta, Canada.

The fate of mercury (Hg) released from dental "silver" amalgam tooth fillings into human mouth air is uncertain. A previous report about sheep revealed uptake routes and distribution of amalgam Hg among body tissues. The present investigation demonstrates the bodily distribution of amalgam Hg in a monkey whose dentition, diet, feeding regimen, and chewing pattern closely resemble those of humans. When amalgam fillings, which normally contain 50% Hg, are made with a tracer of radioactive 203Hg and then placed into monkey teeth, the isotope appears in high concentration in various organs and tissues within 4 wk. Whole-body images of the monkey revealed that the highest levels of Hg were located in the kidney, gastrointestinal tract, and jaw. The dental profession's advocacy of silver amalgam as a stable tooth restorative material is not supported by these findings.

Am J Physiol 1990 Apr;258(4 Pt 2):R939-45

Maternal-fetal distribution of mercury (203Hg) released from dental amalgam fillings.

Vimy MJ, Takahashi Y, Lorscheider FL.

Department of Medicine, Faculty of Medicine, University of Calgary, Alberta, Canada.

In humans, the continuous release of Hg vapor from dental amalgam tooth restorations is markedly increased for prolonged periods after chewing. The present study establishes a time-course distribution for amalgam Hg in body tissues of adult and fetal sheep. Under general anesthesia, five pregnant ewes had twelve occlusal amalgam fillings containing radioactive 203Hg placed in teeth at 112 days gestation. Blood, amniotic fluid, feces, and urine specimens were collected at 1- to 3-day intervals for 16 days. From days 16-140 after amalgam placement (16-41 days for fetal lambs), tissue specimens were analyzed for radioactivity, and total Hg concentrations were calculated. Results demonstrate that Hg from dental amalgam will appear in maternal and fetal blood and amniotic fluid within 2 days after placement of amalgam tooth restorations. Excretion of some of this Hg will also commence within 2 days. All tissues examined displayed Hg accumulation. Highest concentrations of Hg from amalgam in the adult occurred in kidney and liver, whereas in the fetus the highest amalgam Hg concentrations appeared in liver and pituitary gland. The placenta progressively concentrated Hg as gestation advanced to term, and milk concentration of amalgam Hg postpartum provides a potential source of Hg exposure to the newborn. It is concluded that accumulation of amalgam Hg progresses in maternal and fetal tissues to a steady state with advancing gestation and is maintained. Dental amalgam usage as a tooth restorative material in pregnant women and children should be reconsidered.

 

Re: Dental mercury is a real threat (long) » JrBecker

Posted by Larry Hoover on May 8, 2003, at 11:17:45

In reply to Re: Dental mercury is a real threat (long) » Larry Hoover, posted by JrBecker on May 3, 2003, at 13:32:23

> Larry, quite fascinating. Does a general dentist typically screen for high levels of mercury if requested? And would these tests actually tell something useful? In other words, is there some sort of standard measure of mercury levels that would warrant action? Or is it really much more hit or miss than that and the only way to see if the fillings have an effect is to actually remove them? Would like to know since I have a few myself.
>
> Let us know if you have any instinct on this when you get back midweek. Thanks.
>
> JB

I have never found a more scientifically balanced site than this one (I just discovered it myself, and I haven't thoroughly studied every angle they report, but I am extremely happy to have found it):

http://www.algonet.se/~leif/AmFAQigr.html

It quite rationally discusses what the scientific studies have *really* demonstrated; in other words, the questions actually answered in a research report are not always accurately reflected in the conclusions reached by the authors of the studies, or the gist reported in secondary sources. I heartily recommend a thorough reading of this FAQ. It is very well-referenced.

The Life Extension Foundation (LEF) is a little bit on the fringe, but they are generally quite responsible in their reporting. They have an article at:

http://www.lef.org/magazine/mag2001/may2001_report_mercury_1.html

Lar

 

Re: A quack means a dentist using quicksilver » stjames

Posted by Larry Hoover on May 8, 2003, at 11:23:41

In reply to Re: Dental mercury is a real threat (long), posted by stjames on May 4, 2003, at 15:19:15

> > About Quackwatch: Dr. Barrett, the dude who runs the site, has been successfully sued for providing biased and defamatory information. Take him with a grain of salt. He generally ignores any science that doesn't fit with his preconceived notions. That's not to say that he's always wrong, but he is often so.
>
>
> So if the courts say it is not good science or heath, that's it ? All this tells me is the Qwacks have good lawyers and Qwackery is big business. Barrett is a zellot, but you, Larry
> as a man of science (at least that is the role
> you play here) quoting law and making it science
> fact has given me pause to disgreguard your posts.

So be it.

You may be interested to discover that the very term "quack" was first used to describe those dentists using quicksilver (i.e. mercury) amalgam fillings in their patients.

Additional links:

On the Instability of Amalgams
http://www.gbg.bonet.se/bwf/art/instability.html

The Dental Amalgam Issue
http://www.amalgam.org/

Neurobehavioral effects from exposure to dental amalgam Hgo: new distinctions
between recent exposure and Hg body burden.
http://www.faseb.org/fj/august98/ECHEVERR.html

Correlation of dental amalgam with mercury in brain tissue
http://www.nvbt.nl/hot-metalen4.html

Amalgam
http://www.medsci.uu.se/occmed/webkurs/trends/hg.htm

Health Canada Position Statement
on Dental Amalgam
http://www.hc-sc.gc.ca/hpb-dgps/therapeut/zfiles/english/publicat/dental_position_e.html

Dental Amalgam Controversy
http://www.heall.com/body/healthupdates/dentistry/almagam.html

Amalgam Fillings:
Do Dental Patients Have a Right to Informed Consent?
http://www.fplc.edu/risk/vol2/spring/royal.htm

Dental Amalgam Litigation Bibliography
http://lawschool.stanford.edu/library/special/cavitybib.html

Open Directory - Health: Alternative: Non-Toxic Living: Mercury and Amalgams
http://dmoz.org/Health/Alternative/Non-Toxic_Living/Mercury_and_Amalgams/

Lar


 

Re: A quack means a dentist using quicksilver

Posted by stjames on May 8, 2003, at 12:25:52

In reply to Re: A quack means a dentist using quicksilver » stjames, posted by Larry Hoover on May 8, 2003, at 11:23:41

Sigh,

Well for me this becomes a non issue, as I indicated in the post above I have a large amount
of amalgam and feel taking it out would be
a health risk, do to increased exposure. Not to mention the cost and what to use in its place.
So I tend to ignore what I cannot change.

Also, since MattDDS is not answering my questions
I am tending not to view his opinions as valid.
I would like to hear his opinions on my options,
if he thinks I have any.

So, what say you, Larry ? Any ideas for dealing
this load of mercury in my mouth ? Please don't say, "Take it out" as I do not have that kind of money !

 

Re: A quack means a dentist using quicksilver

Posted by stjames on May 8, 2003, at 12:33:41

In reply to Re: A quack means a dentist using quicksilver » stjames, posted by Larry Hoover on May 8, 2003, at 11:23:41

Hmmm,

Reading over all of this I may not of been clear.
I do not question that mercury is toxic, I just feel the ways to remove it and options to replace it are worse.

 

Re: A quack means a dentist using quicksilver

Posted by Larry Hoover on May 8, 2003, at 14:18:41

In reply to Re: A quack means a dentist using quicksilver, posted by stjames on May 8, 2003, at 12:25:52

> Sigh,
>
> Well for me this becomes a non issue, as I indicated in the post above I have a large amount
> of amalgam and feel taking it out would be
> a health risk, do to increased exposure. Not to mention the cost and what to use in its place.
> So I tend to ignore what I cannot change.
>
> Also, since MattDDS is not answering my questions
> I am tending not to view his opinions as valid.
> I would like to hear his opinions on my options,
> if he thinks I have any.
>
> So, what say you, Larry ? Any ideas for dealing
> this load of mercury in my mouth ? Please don't say, "Take it out" as I do not have that kind of money !

One of the simplest interventions is to increase your selenium intake. The covalent compound of selenium and mercury has a solubility in water that is so low it is almost unmeasurable (it's somewhere around 10 to -70). Selenium supplementation is synergistic with vitamin E, so always take E with selenium. Vitamin C has also been suggested as a possible strategy.

Sci Total Environ 2000 Jan 17;245(1-3):15-24

An assessment of selenium to mercury in Greenland marine animals.

Dietz R, Riget F, Born EW.

National Environmental Research Institute, Department of Arctic Environment, Copenhagen, Denmark. rdi@dmu.dk

Information on mercury and selenium molar relation in muscle, liver and kidney tissue of Greenland marine animals is presented. In the majority of the samples selenium was present in a molar surplus to mercury. This was most clear in molluscs, crustaceans, fish and seabirds. A 1:1 molar ratio was found in tissues of marine mammals with high mercury concentrations (above approx. 10 nmol/g). This was most clearly demonstrated for liver and kidney tissue of polar bear and for ringed seal with high mercury concentration in the liver. These findings support previous results found in liver tissue of marine mammals, suggesting that methyl mercury is detoxified by a chemical mechanism involving selenium. If the anthropogenic release of mercury to the environment increases in the future due to increasing energy demands, species such as polar bears and seals with high tissue mercury concentrations should be monitored to elucidate whether this protective mechanism can be maintained in target organs.

Sci Total Environ 1984 Sep;38:33-40

Selenium and its interrelation with mercury in wholeblood and hair in an East Greenlandic population.

Hansen JC, Kromann N, Wulf HC, Alboge K.

138 Blood samples and 12 hair samples from the district of Angmagssalik, East Greenland, have been analysed for selenium and mercury. It was found that selenium like mercury, was absorbed in accordance with the amount of marine food eaten. The mean blood concentration in the group eating most marine food was 173 and 186 micrograms Hg/1 for men and women, respectively, while in the group eating the lowest quantity of marine food, the mean values were 86 and 118 micrograms Hg/1. In blood, the selenium and mercury did not correlate in individuals, but only in groups according to eating habits. On a molar basis, selenium is present in blood in excess as compared to mercury, while the opposite is the case for hair. It is concluded that only part of the selenium interacts with mercury, and that blood, but not hair, reflects present dietary intake. The righ supply of selenium in relation to mercury exposure through the traditional arctic food is probably able to alleviate the hazards from dietary mercury exposure.

Ann N Y Acad Sci 1980;355:212-26

Interactions of vitamin E and selenium with mercury and silver.

Ganther HE.

It is well established that the toxicity of silver and methylmercury is suppressed by the presence of low levels of vitamin E or selenium in the diet, but little is known of the mechanisms involved. Silver induces a conditioned deficiency of selenium in rats, as shown by its effects on tissue levels of selenium and glutathione peroxidase (a selenoprotein), but methylmercury does not. Supplements of selenium do not decrease mercury levels in tissues of animals given methylmercury, and animals given selenium plus methylmercury may accumulate high levels of mercury without signs of toxicity. Although an equimolar accumulation of selenium and mercury in tissues sometimes occurs and could lead to mutual detoxification, such a coaccumulation is not always linked to protection. The only known functions of vitamin E and selenium are related to the prevention of oxidative damage. It is possible that their protective effects against heavy metals may involve such functions, thus accounting for the protection afforded by low levels of the nutrients against high levels of the metal toxicants.


 

Dental Amalgam (longer) » Larry Hoover

Posted by mattdds on May 8, 2003, at 14:33:45

In reply to Re: Dental amalgam increases disease? (long) » mattdds, posted by Larry Hoover on May 8, 2003, at 9:57:19

Hi Larry,

It is always a waste of time to try to convince someone else of something they have a strong bias or opinion against. This type of exchange will only lead the both of us to strengthen our existing opinions.

However, I was not impressed with either the sources you cited or the quality of studies they performed. You did provide an overwhelming **number** of studies, but I think the quality of most of them was pretty poor. A few of them, seemed like zealots, with strong biases. Kind of like the anti-fluoridation zealots or the people that say that using psychiatric drugs will cause creepy, mysterious diseases. If one wants to find evidence supporting something, it can be found if one looks hard enough. All it takes these days is a search on Google or pubmed. The problem is, in the meanwhile, better performed studies may overlooked, because they don’t fit the preconceived notions.

You quoted “The Rocky Mountain Research Institute” a couple of times. One of their articles was attempting to make a link between dental amalgam and Alzheimer’s disease. I thought that they pretty much had the etiology of Alzheimer’s nailed down; having to do with beta-amyloid plaques that accumulate in the brain. You are taking a very controversial and unsupported view on this one. And you will have to do better than one small study containing 48 people, performed by a highly biased “research” group.

For what it’s worth, here is the statement from the Alzheimers Association, who as far as I know, are advocates for those with the disease, don’t give a damn about us quack American dentists (as you put it) being sued, and don’t have any connection with the evil dental amalgam manufacturers:

"According to the best available scientific evidence there is no relationship between silver dental fillings and Alzheimer's." (Alzheimer's Association)

On a similar note:
Saxe SR, Wekstein MW et al. "Alzheimer's disease, dental amalgam and mercury", JADA 1999 Feb;130(2):191-9

This study consisted of 68 human subjects with diagnosed Alzheimer's disease and 33 control subjects without Alzheimer's to determine mercury levels in multiple brain regions at autopsy and to ascertain the subjects' dental amalgam status and history. Conclusions: Mercury in dental amalgam restorations does not appear to be a neurotoxic factor in the pathogenesis of this disease. The authors found that brain mercury levels are not associated with dental amalgam, either from existing amalgam restorations or according to subjects' dental amalgam restoration history. Furthermore, dental amalgam restorations, regardless of number, occlusal surface area or time, do not relate to brain mercury level.

I think these are pretty clear.

You quoted the same group as having done some research about a link between multiple sclerosis and amalgam. Boy, these guys are on a roll!

Here is what the National Multiple Sclerosis Society said about that:

"There is no scientific evidence to connect the development of MS or other neurological diseases with dental fillings containing mercury." (National Multiple Sclerosis Society)

Again, pretty clear, I think.

The Academy of Pediatrics has said this:

"There is no scientific evidence of any measurable clinical toxic effects [of dental amalgam]." (American Academy of Pediatrics)

From reading your posts, I picked up on a sense of mistrust of large health organizations. E.g. the ADA, and perhaps groups like the ones I just cited. Am I correct on this? If so I apologize. If it is true, I would be curious as to why you feel that your opinions are better than the overwhelming majority of your peer scientists.

Also, you wrote:

>>Were I to rewrite that phrase today, I would use "place" instead of "store". I did not mean to suggest environmental concerns in any respect. You're a dentist, right? It just hit me that you are mattdds. You have very exacting protocols on what to do with excess amalgam, right? You wear rubber gloves to protect against even trivial dermal exposure, correct? But you have no problem placing an amalgam on a buccal surface, guaranteeing exposure to cheek skin, right? Or on an occlusal surface, even in bruxists? Doesn't this seem to suggest different standards being applied in these two situations?

First, no I’m not a dentist...yet. I am a 4th year dental student.

Second, I don’t really understand what you are asking (or implying?) here. Since about 1950 we wear gloves ANYTIME we are in a patient’s mouth. This has nothing to do with amalgam but with infectious disease control. We follow the EPA’s and OSHA’s guidelines on amalgam removal and disposal not so much because we secretly and devilishly know how bad amalgam **really** is and want to avoid it ourselves, but more because we don’t want to get our practice shut down by the EPA. These aren’t **our** “exacting protocols" as you suggested (implying that we were trying to protect ourselves from "trivial dermal damage", while unscrupulously and maliciously placing buccal amalgams, while knowingly harming the patient) but ones that have been imposed on us by larger organizations outside our control, so we just follow the rules. As far as buccal pit amalgams, I am confused here too. First off, they are (or should be) placed with a rubber dam until the amalgam sets. Also, I thought the main concern was during mastication? At least that was when you claimed mercury was released, am I right? Mastication involves the occlusal surfaces of the teeth, not the buccal (unless you have some extremely abnormal occlusal morphology). So, I am actually **less** concerned about a buccally placed amalgam restoration. By the way, I personally don’t put amalgam in buccal pits. Amalgam is suitable for high-stress bearing areas, namely, the occlusal surfaces of posterior teeth. Composite is now the material of choice for buccal caries. As for patients who are bruxers, we have a few options. My own choice would be to place a gold or high-noble inlay, which most patients not to mention insurance companies will not pay for. We can also place a porcelain restoration – which would completely obliterate the opposing dentition, or fracture. Again these are tremendously expensive. We can also place a composite filling, for which the patient will definitely hate us, because they will either wear out within a week or fracture completely. Then we would have to remove the composite, and inevitably more tooth structure to place a new (probably a crown, this time) restoration. We can also let the tooth continue to decay, but that would eventually either require an extraction (most patients would prefer the nominal mercury exposure) or a root canal, then a post-core and crown (upwards of $1500, minimum). Lastly, we could place an amalgam for $75. If you were put in the same position, with similar economic restraints, what would you do Larry? If you have some secrets that you are holding from us morons in the American dental community, please reveal them to us! Help us out here, perhaps we are missing something terribly obvious. You see, I am damned if I do, damned if I don’t, don’t or don’t. Then I have to deal with people like you telling me how big of a quack I am for doing the best that I know how, without offering any good alternatives. Do you still wonder why dentists have a high suicide rate, Larry?

Your comments reveal a mistrust of dentists in general, I am curious as to why. Do you feel **all** dentists are similarly malicious? Or just the ones that use amalgam (almost all of them)?

Incidentally, I imagine in my practice, I will avoid amalgam altogether, even though I feel it is a superior restorative material, as well as a safe and affordable one. Composite resins are getting pretty strong nowadays, approaching the qualities of real tooth (amalgam is still quite a bit stronger). They are also quite esthetic. My school clinic is pushing posterior composites, such as Sur-Fil (a glass reinforced, packable resin composite). Anything that is too large for composite, I will probably treatment plan for a crown or an onlay. I am hoping that posterior composites will supplant amalgam, and think it will in the near future, just so I can stop hearing people freak out about it. I think the scare about amalgam in the teeth becomes just another source of obsession and hypochondriasis, which in my view are much more pathologic than the actual harm done by the mercury. Either way, I will not be sad to see it go.

Also, you said:

>>I would ask you this: "If mercury amalgams were being proposed today as an innovative restorative material for dental caries, do you think that they would get past the regulatory approval process in existence today?" I can guarantee you, they would not get past the committee stage, let alone get into animal trials.

Someone recently posed the same question about aspirin, and speculated that aspirin would likely not be deemed as safe for use. So I agree, amalgam would probably not even be given the chance to be used. But I am not so sure that would be a good thing. I still think aspirin is a great drug and safe, and still think that dental amalgam is a great material, and safe. The approval process is slow enough as it is, and getting slower. I think that the harm done by the over cautiousness of the regulatory groups is much more detrimental, and offsets the good they do by “protecting” us. Plus, I don’t think they are always right about things, e.g. they approved fenfluramine-phentermine combos in the recent past, only shortly later to find out they screwed up - big time. I don’t believe in a total Laissez-Faire attitude toward drug development, but believe that the process is much too slow as it stands.

Finally, the axiom of science you quoted is true, absence of evidence does not mean evidence of absence. So by this, you seem to be conceding somewhat that there is pretty scant evidence for what you are claiming. I think it is only in the X-files or conspiracy theory type thinking that absence of evidence equals evidence. You even mentioned being aware of major, large epidemiological studies that failed to show correlations between amalgam and disease. How do you reconcile these findings with your beliefs?

Sure, you are entitled to opinions. Believe what you will. But in the process, please make sure not to scapegoat people (dentists) for diseases that we know very little about. Who knows, maybe small, chronic doses of mercury from amalgams will indeed turn out to be the root of all evil. When this evidence turns up, I will concede, and resign to hell, which will be my rightful inheritence, along with the other dentists who sold their souls to amalgam for a Lexus. But I just don’t believe this evidence exists or ever will.

Thanks,

Matt

 

For StJames » stjames

Posted by mattdds on May 8, 2003, at 15:20:21

In reply to Re: A quack means a dentist using quicksilver, posted by stjames on May 8, 2003, at 12:25:52

StJames,

I actually had a pretty long response to your questions written out, but I got up to go get something to eat, and my wife mistakenly closed it. I was so bugged that I lost all the work, because I actually typed out what would have been a pretty thoughtful response.

You have the right to regard my opinios as you will. I am not offended by this. Truthfully, I don't have any special or priveleged information outside what anyone else could obtain.

Here goes:

>>I have way over 100 amalgam fillings, top and bottom, past the canines. It is common in my fathers family to
have large #'s of cavities till about 18 and then have almost none

This is actually a very common pattern, my family has the same one. The reason they stop might have something to do with the elimination of deep grooves that are not accessible to bristles of a toothbrush. So when a filling is placed, it is more hygienic. The better alternative to this would have been to get sealants placed. This accomplishes the same thing by sealing those inaccessible grooves, but is done before the decay starts, so the tooth structure is conserved.

But 100 amalgam fillings? I am not sure how this would be possible! Personally, if I saw a patient with that much decay I would have planned for crowns, hands down. This would have eliminated any problems you personally had with amalgam at the same time.

What you referred to as “epoxy” fillings are composite resin fillings, and they are vastly better these days than before (back in the 70’s you said?) They should not fall out, especially in anterior teeth (front teeth) because they actually micromechanically bond to dentin tubules in the teeth. So any dentist these days would use composite resin in anterior teeth, without question. There are absolutely no advantages in using amalgam in front teeth (not to mention, it looks very bad), and every reason to use composite.

The back teeth are a different question. If your question is about chronic amalgam exposure and whether you should remove your fillings for health reasons, well you can get an idea of my opinion about that in the previous posts. Breifly, I don’t feel they cause or contribute in any measurable way to disease (including psychiatric problems), and don’t think that removing them would be of any good to you. Larry has different opinions on this, so you can weigh what we have both said and decide for yourself.

Composite is getting better and better for back teeth, and the strength is getting really good, but not as good as amalgam for stress bearing areas. I don’t think they would typically fall out, but that all depends on the size, location, and if a cusp (pointy part) is decayed or broken off. I really could not say for sure without seeing your teeth in person, so this is just general information.

>> So it would seem removing this much amalgam would
render a huge dose of mercury into my body

Yes, it does, especially if proper precautions are not taken, such as rubber dam placement. But I think Larry’s argument is more about chronic exposure and toxicity, which (he feels) happens when they stay in the mouth for a long period. From what I understand now, transiently high mercury levels are not as big of a deal (to people who are concerned about this, and advocate removal).

Imagine how much money dentists would make if they routinely suggested removal of amalgam fillings and replacement with composite! Why aren’t they doing this? The same reason most dentists advocated fluoridation back in the 60’s and 70’s, because it is in the patients best interest. It is deceitful to tell people to remove their amalgams for health reasons, because there is no reliable evidence saying that is the case. So if American dentists were the quacks Larry says we are, we would be just salivating, thinking about the fat cash we would be making by replacing the legions of amalgams occupying the mouths of Americans!

>>With hind sight, what would of been a better option for a kid who has 6 cavities every 6 months, for over 10 years ?

One word: Sealants!

>>Gold seems too expensive on this scale.

I would imagine! There are other non-amalgam materials besides gold, such as porcelain fused to metal crowns (don’t worry, no amalgam!), porcelain onlays, composites.

My question for you is this: Are you getting the amalgams replaced because they are defective or have recurrent decay? Or are you replacing them because you are worried about the mercury load? If it is the former, than you will likely need some crowns or onlays, if you have as many fillings as you say. If it is the latter, than my suggestion is “If it ain’t broke, don’t fix it!”, and you know my position on whether amalgam causes disease.

Did I answer everything? Let me know if I can answer anything else. Again, I have no special knowledge, but will do the best I can. I hope this helps some.

Thanks,

Matt

 

Re: Dental Amalgam (longer)

Posted by Larry Hoover on May 8, 2003, at 15:41:27

In reply to Dental Amalgam (longer) » Larry Hoover, posted by mattdds on May 8, 2003, at 14:33:45

> You quoted “The Rocky Mountain Research Institute” a couple of times. One of their articles was attempting to make a link between dental amalgam and Alzheimer’s disease. I thought that they pretty much had the etiology of Alzheimer’s nailed down; having to do with beta-amyloid plaques that accumulate in the brain. You are taking a very controversial and unsupported view on this one. And you will have to do better than one small study containing 48 people, performed by a highly biased “research” group.

I recall posting no article referencing amalgam vis a vis Alzheimer's. I have no idea what you're talking about.

> You quoted the same group as having done some research about a link between multiple sclerosis and amalgam. Boy, these guys are on a roll!

I suggest you re-read the article. It did not relate MS to amalgam, but associated psychological variables to amalgam within a selected population, i.e. subjects with MS. I included it to suggest that subjects with comorbidities may be more vulnerable to the adverse effects of mercury exposure. If only someone would do a similar study on depressives. I don't recall ever seeing one.

> Your comments reveal a mistrust of dentists in general, I am curious as to why. Do you feel **all** dentists are similarly malicious? Or just the ones that use amalgam (almost all of them)?

I don't hold dentists responsible for their training. I hold no negative opinions of dentists per se. Dentists are scientists, and scientists can be the most stubborn people on the planet, IMHO.

>I think the scare about amalgam in the teeth becomes just another source of obsession and hypochondriasis, which in my view are much more pathologic than the actual harm done by the mercury. Either way, I will not be sad to see it go.

I was very careful to suggest that somatization was a valid explanation for many who believe they have amalgam disease. However, that explanation cannot be used to suggest that there are no valid cases, which seems to be the case in the dental literature. I reviewed actual papers some years ago, a stack well more than a metre in height. I no longer have them (their title was part of the research contract), so I'm stuck with sourcing abstracts on the 'net right now. I didn't come to my concerns lightly.

>You even mentioned being aware of major, large epidemiological studies that failed to show correlations between amalgam and disease. How do you reconcile these findings with your beliefs?

I did so in my prior posting (I thought). It may be that there are only a small set of subjects whose sensitivity to mercury make their symptoms directly related to amalgam. Dilution by including these subjects in unselected populations would preclude obtaining significant findings. To paraphrase the axiom, the failure to find significance in a study does not show there was nothing significant to find.


> Sure, you are entitled to opinions. Believe what you will. But in the process, please make sure not to scapegoat people (dentists) for diseases that we know very little about. Who knows, maybe small, chronic doses of mercury from amalgams will indeed turn out to be the root of all evil. When this evidence turns up, I will concede, and resign to hell, which will be my rightful inheritence, along with the other dentists who sold their souls to amalgam for a Lexus. But I just don’t believe this evidence exists or ever will.

See you there. <wink>

> Thanks,
>
> Matt

Regards,
Lar

 

Re: the word quack » mattdds

Posted by Larry Hoover on May 8, 2003, at 15:48:19

In reply to For StJames » stjames, posted by mattdds on May 8, 2003, at 15:20:21

I just want to be clear on one thing, Matt. I found it to be exceedingly ironic that Quackwatch called opponents of the use of mercury amalgam quacks, when the word was originally coined to describe proponents of its use.

Other than that descriptive posting, I have not nor will I ever use the word to describe dentists. I am sorry that you believe that I have made such use, but I did not.

Lar

 

Re: For StJames

Posted by stjames on May 8, 2003, at 16:55:49

In reply to For StJames » stjames, posted by mattdds on May 8, 2003, at 15:20:21

> But 100 amalgam fillings? I am not sure how this would be possible! Personally, if I saw a patient with that much decay I would have planned for crowns, hands down. This would have eliminated any problems you personally had with amalgam at the same time.

No decay, 100 is my best guess, as I remember
the doc finding 6 cavities every 6 months, ie 12X10 = ~100. My mother indicated she felt the
doc was a little over zelous in filling things
but later in life I had a consult with an Oral
Surgeon who indicated I had excellent care.
I do not think these were grooves as most were demonstrated by X-ray.


> >>With hind sight, what would of been a better option for a kid who has 6 cavities every 6 months, for over 10 years ?
>
> One word: Sealants!

Did they have those in the 70's ? I know kids get them today.


> My question for you is this: Are you getting the amalgams replaced because they are defective or have recurrent decay? Or are you replacing them because you are worried about the mercury load? If it is the former, than you will likely need some crowns or onlays, if you have as many fillings as you say. If it is the latter, than my suggestion is “If it ain’t broke, don’t fix it!”, and you know my position on whether amalgam causes disease.

I HAVE NO DECAY !!!! Far too much money was put into my mouth and I am also a tooth snob, so my teeth are well cared for (heheh)

NO, I have no intention of removing the amalgams.
I grind too much for other options & am not convinced there is an issue here. (Remember Matt, I am the one who said this is a qwack)

 

Three hours in the chair

Posted by leeran on May 8, 2003, at 18:04:10

In reply to For StJames » stjames, posted by mattdds on May 8, 2003, at 15:20:21

I just got home from three hours in the dentist's chair. I'm not an atheist, but that expression "there are no atheists in foxholes" kept running through my mind during those 180 minutes (just substitute foxhole for dental chair).

I asked the dentist about his method of removing mercury (our conversation took place about three feet from the mercury warning sign) right before he started working. I asked specifically about removal/vapors, etc.

He explained the word amalgam (I already knew the meaning) and said he never even wears a mask when removing amalgam fillings . . .

What can you do? You're sitting there - ready to roll, plus, I trust this doctor. The words "blind faith" come to mind, but he's the absolute best dentist (IMO) I found listed on our dental plan (I did a lot of research before deciding choosing him from a list of about 180 providers in our area).

His comment (re: mercury) was that most women have five pounds of it in their breasts from all the fish they've eaten over the years (this guy is pretty outspoken and apparently feels comfortable making exaggerated statements around patients).

Once he started drilling he found that the back tooth and the one next to it (I don't know the corresponding numbers) were too far gone to support porcelain fillings so the plan changed to porcelain crowns midway through the work.

Even with a temporary structure in place I can see a nice difference in the one side of my mouth (I won't get as good of radio reception anymore) but I wouldn't go to the expense to ever have all of them removed until it became medically necessary. For one thing, I couldn't take that much time under the drill without sedation (which he offers but he didn't think was necessary for this situation).

I suppose the Lexapro is kicking in nicely because I was surprisingly calm before the appointment, and in a weird way, even during the procedure.

I told someone on this thread that I would report back so that's the news. I don't know that my opinions about mercury have changed. I certainly would prefer porcelain or resin in the future but $785 per tooth for a porcelain filling is pretty darned steep.


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