Newsgroup: it.salute
Titolo: Re: F.A.Q. Amalgama

suscitare e vista sopratutto la disinformazione che circola in Internet
http://tinyurl.com/4tv7r
http://tinyurl.com/5f6y7
http://web.tiscali.it/ODONTOPAGE/relazione.htm
questi due post saranno il mio solo contributo. 
Mi sarei un po' scocciato di ripetere sempre le stesse cose 
plonk sul thread 
Fate vobis e buona fortuna 
-- 
sgas ® UIN  69225877  sgas [*at*]
sgas.it
" There are in fact two things, science and opinion;
 the former begets knowledge, the latter ignorance"
( Ippocrate )
 

dell'amalgama? In Europa? Nel resto del mondo?
Dichiarazione congiunta 
FDI - World Dental Federation 
&
OMS - Organizzazione Mondiale Sanità 
************
PREAMBOLO 
La carie dentale e una malattia molto comune e la sua prevenzione
rientra nei compiti prioritari dell'O.M.S. Nonostante i notevoli
successi conseguiti con la prevenzione, continuano a esserci lesioni
cariose, alle quali bisogna rimediare con i restauri appropriati, dopo
aver eliminato il tessuto cariato. L'amalgama dentale, ottenuta
combinando mercurio e leghe a base d'argento, e' sempre stata usata
come materiale per i restauri dentali. Mentre da una parte l'attuale
peso dell'evidenza permette di ritenere che i materiali per il
restauro dei denti, amalgama compresa, sono da considerarsi sicuri ed
efficaci, dall'altra affiorano delle riserve a proposito degli effetti
sulla salute del mercurio contenuto nell'amalgama. Dopo aver
sottoposto a una valutazione una grande quantità di dati talvolta
contraddittori derivati da fonti diverse, l'OMS ha elaborato la
seguente dichiarazione: 
1. Uso dell'amalgama dentale L'amalgama e un materiale di uso
frequente nel restauro dei denti cariati. E stato usato con successo
per più di un secolo, e la sua qualità e andata sempre migliorando. I
restauri in amalgama sono durevoli e cost-effective; pero' non hanno
il colore dei denti. Malgrado tutte le ricerche dedicate allo sviluppo
di materiali per il restauro dei denti, al momento non esiste
materiale per otturazioni dirette che abbia la vastità di indicazioni
per il suo impiego, la facilita di manipolazione e la bontà di
proprietà fisiche dell'amalgama. I materiali di restauro alternativi
all'amalgama sul mercato attuale aumentano considerevolmente il costo
delle cure dentarie. 
2. Sicurezza dell'amalgama dentale :  I restauri in amalgama sono
considerati sicuri, ma i componenti dell'amalgama e di altri materiali
per i restauri dentari in alcuni rari casi possono provocare effetti
collaterali locali o reazioni allergiche. Non e stato dimostrato che
le piccole quantità di mercurio che si liberano dai restauri in
amalgama, specialmente durante la loro esecuzione o eliminazione,
provochino altri effetti dannosi per la salute. In conseguenza delle
preoccupazioni sugli effetti dannosi del mercurio, può capitare che
alcuni pazienti, con o senza sintomi, richiedano, l'eliminazione dei
loro restauri in amalgama. Esistono alcuni studi di casi clinici e
relazione informali, ma non sono mai stati pubblicati studi
controllati che dimostrano effetti dannosi sistematici dovuti a
restauri in amalgama. ***Allo stato attuale non esiste prova
scientifica che dimostri che i sintomi di carattere sistemico
regrediscano, eliminando i restauri in amalgama.*** Perciò, dopo un
esauriente esame del cavo orale e dopo il trattamento odontoiatrico
appropriato, si deve provvedere a inviare questi pazienti ad altri
sanitari per accertare la diagnosi ed eseguire il trattamento
indicato, se i sintomi persistono. 
3. Rischio professionale del personale sanitario
Se le condizioni di lavoro non sono organizzate in maniera corretta,
esiste un rischio potenziale per la salute del personale che si occupa
della salute orale. L'adozione dei requisiti igienici appropriati per
la manipolazione del mercurio associata al controllo continuo dei
vapori nell'ambiente di lavoro riduce in maniera determinante
l'esposizione al mercurio negli studi dentistici. 
4. Salvaguardia dell'ambiente . 
 Il mercurio usato dai dentisti può contaminare l'ambiente in seguito
allo smaltimento dei rifiuti derivanti dagli studi dentistici. Sono
disponibili dispositivi che trattengono i residui del metallo che
rimangono durante l'esecuzione delle otturazioni in amalgama o durante
la loro eliminazione. La tecnologia attuale permette la raccolta dei
residui di amalgama e il loro riciclaggio, per ridurre l'inquinamento
ambientale da mercurio, compreso l'inquinamento conseguente alle
cremazioni. 
5. Opinione pubblica e mass media
 Al giorno d'oggi in tutto il mondo avviene continuamente uno scambio
di informazioni riguardanti l'amalgama dentale. Per ragioni di
protezione ambientale alcuni paesi proibiscono qualsiasi uso di
mercurio, comprese le amalgama dentali. In seguito a iniziative
pubblicitarie nei mass media, spesso si creano situazioni di
incomprensione su questo punto, nei paesi che hanno fatto ricorso a
misure proibizioniste. Come conseguenza ripetutamente si richiedono
informazioni a riguardo dell'innocuità dell'amalgama dentale e si
pretende l'eliminazione delle otturazioni in amalgama
.*** Le attuali nozioni scientifiche _dimostrate_ !!  permettono di
affermare che i materiali odierni per il restauro dei denti, compresa
l'amalgama dentale, vanno considera sicuri ed efficaci***.
Tuttavia si presentano reazioni biologiche occasionali avverse a
questi materiali le quali devono essere trattate su base individuale.
L'Organizzazione mondiale della Sanità riconosce l'importanza del
monitoraggio continuo della sicurezza e dell'efficacia di tutti i
materiali impiegati per il restauro dei denti. 
********************
COMMITTEE ON TOXICITY OF CHEMICALS IN FOOD, CONSUMER PRODUCTS AND THE
ENVIRONMENT
STATEMENT ON THE TOXICITY OF DENTAL AMALGAM
Introduction
1. The Committee has been asked to advise the Medical Devices Agency
on the toxicity of mercury in dental amalgam. This request was made in
order to helpformulate the United Kingdom's response to the report of
an ad hoc group of experts established by the European Commission to
consider dental amalgam within the context of the Medical Devices
Directive.[1] Particular topics on which theCommittee's views were
sought included: the risk assessment, the risks of neurotoxicity or
nephrotoxicity, the risks of amalgam use during pregnancy or in
patients with renal disease, and the adequacy of the toxicological
database. 
Background 
2. The Committee last considered the safety of dental amalgam in 1986.
At that time we recognised that some mercury may be released from
completed restorations but were of the opinion that the use of dental
amalgam is free from risk of systemic toxicity and that only a very
few cases of hypersensitivity occur.[2]
3. Recently there has been a resurgence of interest in the toxicity of
mercury indental amalgam. We have been informed that dental
restorative materials, including dental amalgam, are considered to be
medical devices under the terms of theMedical Devices Directive
93/42/EEC and have seen the report of the ad hoc group established to
review dental amalgam in relation to this directive.[1] Exposure to
dental amalgam and intake of mercury
4. We have been informed that the use of dental amalgam in the UK
hasdeclined. Whereas the annual placement rate in 1986 was 30 million
amalgam restorations per year, the estimate for 1996 in National
Health Service patients inEngland and Wales of 12 to 13 million
restorations is considerably lower. The decline is possibly due to a
decrease in the incidence of dental decay as well as areduced usage of
amalgam by dentists.
5. The Committee noted that there were problems in accurately
measuring the intake of elemental mercury from amalgam fillings and
that other sources ofexposure, such as the diet, might result in the
absorption of mercury in other chemical forms (e.g. as cations or as
organo-mercury compounds). It was  understood that the contribution of
dietary intake to mercury exposure was of a similar order as that from
amalgam fillings. It was agreed that the placement orremoval of such
fillings were occasions during which the greatest exposure of
individuals to mercury from the amalgam could occur.
6. We also noted that when studies of metabolism and excretion of
mercuryhave been carried out these were undertaken most frequently in
individuals who were exposed occupationally to mercury. Such exposures
might not be relevant tothe individual exposed to the trace quantities
(estimated as 1 to 5 micrograms (ug) per day, or in a more recent
paper as 1 to 2 ug per day [3]) released from dentalrestorations in
situ.
Toxicity of mercury to humans 
7. The Committee considered the toxicity of mercury to the kidney and
noted that epidemiological studies of the effects of dental amalgam on
renal function havebeen conducted only in healthy subjects. In these
individuals mercury exposure from dental amalgam was not associated
with the urinary excretion of  N-acetyl-*-Dglucosaminidase, which is
an enzyme that is a sensitive indicator of kidneydamage. The Committee
concluded that, in healthy subjects, exposure to mercury  from dental
amalgam was not associated with nephrotoxicity. On the basis of the
available data it was not possible to draw any conclusions about the
effects ofmercury from amalgam on persons with pre-existing renal
disease.
8. The Committee agreed that immunologically-mediated mercury-induced
glomerulonephritis (a form of kidney damage) was poorly understood and
thatstudies in occupationally-exposed individuals indicated the
existence of a possible  dose-response relationship for this effect.
This could be an appropriate subject forfurther research. In our last
consideration of dental amalgam we noted the occurrence of a few cases
of hypersensitivity but considered that this area did notwarrant
further study.
9. The Committee recognised that neurotoxicity was of potential
concern. Both elemental mercury and organo-mercury compounds can
contribute to this. The major source of organo-mercury compounds is
the diet but the Committee noted  that methylation and demethylation
of mercury compounds by micro-organisms inthe large bowel might occur.
Evidence on the balance of these reactions is limited. The Committee
accepted that exposure to mercury vapour is of greater concern for
dentists and their staff than for patients.
10. The Committee noted that there was some evidence that mercury
could be taken up by the fetus and placenta during pregnancy, however
there was a lack ofdata that would determine whether the mercury was
present in an unreactive,  metallothionein-bound form. Apart from one
study [4] which had been severelycriticised,[5] and which was
discounted, there was no evidence that occupational exposure to
mercury during pregnancy in modern dental practice was harmful.There
is no evidence that the placement or removal of amalgam fillings
during pregnancy is harmful. 
Conclusions and Recommendations
11. The Committee welcomes the report [1] and appreciates the
opportunity to comment on it. Although the report includes information
published since the Committee last reviewed dental amalgam we
consider that our former conclusions regarding hypersensitivity and
the lack of risk of systemic toxicity remainunchanged.
12. The Committee  concluded that nephrotoxicity was not associated
with exposure of healthy subjects to mercury amalgam from dental
restorations. Also,we consider that neurotoxicity caused by exposure
to mercury vapour is a matter of  more concern in the occupational
setting than in dental patients. 
13. We conclude that there is no available evidence to indicate that
the placement or removal of dental amalgam fillings during pregnancy
is harmful. We are of the opinion , however, that the toxicological
and epidemiological data are inadequate to assess fully the likelihood
of harm occurring in such circumstances. Until appropriate data are
available we  concur with the view that it may be prudent to avoid,
where clinically reasonable, the placement or removal of amalgam
fillingsduring pregnancy.
14. Accordingly, we  consider that pregnant women and patients with
kidneydisease are groups who should be included in future studies. We
recommend that such studies should incorporate measurements of dietary
intake of the variouschemical forms of mercury. Additionally, we
consider that studies to elucidate the mechanism of
immunologically-mediated mercury-induced glomerulonephritisshould also
be included in further research. Studies should be done to ascertain
the kinetics of mercury in the body at low doses and verify whether
the kineticsdetermined from occupational studies are applicable to
patients with dental amalgam restorations.
References 1. Dental Amalgam (1997). A Report with reference to The
Medical DevicesDirective 93/42/EEC from an Ad Hoc Working Group
mandated by The European Commission. [Seen as the draft of June 1997]
2. Committee on Toxicity of Chemicals in Food, Consumer Products and
theEnvironment (1986). Statement on Dental Amalgam prepared for the
Committee on Dental and Surgical Materials. 3. Eley BM (1997). The
future of dental amalgam: a review of the literature.Part 3. Mercury
exposure from amalgam restorations in dental patients.  Br Dent J ,
182:331-338. 4. Sikorski R, Juszkiewicz T, Paszkowskie T and
Szprengier-Juszkiewicz T (1987). Women in dental surgeries :
reproductive hazards in occupational exposureto metallic mercury.  Int
Arch Occup Environ Health , 59:551-557.
5. Larsson KS (1995). The dissemination of false data through
inadequate citation. J Internal Med , 238:445-450.


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Un questionario davvero molto interessante, Val. 
Finora le risposte sono state scarse, brusche (c'č stato addirittura un
plonk) e incomplete.
Spero che rispondano altri esperti. Loro dovrebbero sapere e sarebbe
giusto che ci informassero. 
Saluti.
Aladar
-- 
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