FAN Bulletin 794

April 17, 2007

Dear All,

It is very interesting reading an article published in the British Dental
Journal in 2005 by Dr. Joe Mullen (see below) and comparing that with the
bulletin I distributed yesterday on the myth of fluoridation’s
effectiveness. While, Mullen’s article appeared nearly two years ago, its
existence becomes relevant because it was cited by Professor William Reville
in an Op ed piece in the Irish Times on March 29, 2007, as his sole
reference to counteract recent concerns from the Green Party and others
about the safety and effectiveness of
fluoridation in Ireland.

Joe Mullen is an Irish dentist who has considerable influence in Ireland. He
sat on the infamous Fluoridation Forum which produced one of the worst
national reviews of fluoridation that has found its way on to paper. To give
you an inkling of how bad this report was, out of 295 pages, only 17 dealt
with health effects other than dental fluorosis. Of these only one tissue
was chosen: the bone (nothing on the brain, the thyroid gland, the pineal
gland, the kidney or the issue of subsets of the population which are
particularly sensitive to fluoride). In the Forum health discussion, all the
evidence was derived from other reviews except for one and half pages
devoted to 3 primary studies (and none of course from Ireland where not a
single health study has ever been conducted in over 40 years of
fluoridation). In other words, the Forum spent less time dealing with
primary health studies than they spent on illustrating what a pea sized
amount of tooth paste looks like on a toothbrush!

This same Forum failed miserably to respond to my “50 Reasons to Oppose
Fluoridation” after promising to do so and forming a sub-committee to
address the task. After about 13 months they declared that they didn’t have
enough time and forwarded the task to the Department of Health. It took the
DOH another 3 years before any comments were forthcoming. These appeared
anonymously on their web site and were never sent to me. They were presented
in a higgledy piggledy fashion. After a considerable time disentangling
their generalized answers I found that 20 questions were left unaddressed
and most of the remaining answers had little scientific merit.

Turning to Mullen’s BDJ piece on fluoridation, I will examine the evidence
he mobilizes for fluoridation’s effectiveness (see below) and compare his
treatment of this issue with the arguments I raised in yesterday’s bulletin
(the numbers and titles refer to the sections in yesterday’s piece). I hope
you agree that it is useful to compare our arguments side by side with
theirs on these issues.

1. The level of fluoride in mothers milk Mullen makes no reference in his
article to the very low level of fluoride in mothers milk (0.004 ppm).
2. Fluoride works topically not systemically. Mullen makes no reference to
the extensive literature to the effect that the predominant benefits of
fluoride are derived topically not systemically (Featherstone, 2000, CDC,
1999, 2001) and thus he dodges the tricky problem of explaining why it is
necessary to put fluoride in the water, even while he acknowledges the
benefits of fluoridated toothpaste.
3. Tooth decay is coming down as fast in non-fluoridated as fluoridated
communities. Mullen does not refer to the important studies I referenced
from Leverett (1982); Colquhoun (1984); Diesendorf (1986) or Gray (1987).
4. International comparisons. Mullen does acknowledge that tooth decay is
coming down in non-fluoridated countries in Europe, although does not make
it clear that in most countries the rates are coming down as fast, if not
faster than in fluoridated countries. In mainland Europe he certainly
cannot argue for a “halo effect” (i.e. fluoride moving from fluoridated
areas to non-fluoridated areas) since there is little exporting of food and
beverages etc from countries which are fluoridated to countries which are
not. This is because there are only a few countries which are fluoridated in
Europe: Ireland being the big one with 73% of population drinking
fluoridated water followed by the UK with 10% and Spain somewhere between 3
and 10%. Mullen offers two reasons for the similar rates of decline in both
fluoridated and non-fluoridated countries: 1) Some of these countries use
fluoridated salt. However, that explanation does not explain the situation
in the Netherlands, Belgium, Norway, Denmark, Finland, Iceland or Sweden,
none of which use fluoridated salt or fluoridate their water. 2) All the
countries use fluoridated toothpaste, as does Ireland. However, Mullen
argues for a 50% extra benefit from water fluoridation over and above the
benefit of fluoride from toothpaste. The only evidence he offers to support
this extra benefit from water fluoridation is a study which compared tooth
decay in Northern Ireland with that of the Republic of Ireland.
5. State comparisons. This data was not available to Mullen in 2005.
6. County comparisons. This data was not available to Mullen in 2005.
7. Published cross sectional comparisons. These large important studies
(Brunelle JA, Carlos JP. (1990); Spencer AJ, et al. (1996); Armfield JM,
Spencer AJ. (2004) were available to Mullen, but he chose not to cite them.
Could it be that they showed little, if any, benefit from fluoridation for
permanent teeth and certainly not the “relative disease reduction of 50%” he
claims?
8. Reviews of effectiveness. The review by Pizzo, et al., 2007 was not
available to Mullen but the other two were. It is very surprising he ignored
the review by David Locker conducted for the Ontario government which was
publicly available in 2001. It is even more disturbing, that having cited
the York Review (to downplay health concerns), he failed to discuss the
section of this same review which dealt with effectiveness. Perhaps, Mullen
did not want to draw attention to the fact that most of the studies of tooth
decay are of a poor quality. According to the York Review there have been no
grade A studies (i.e. Double blind, random-control) even though this panel
was reviewing over 50 years of research in this area. Perhaps, Mullen, like
many others, was not impressed with the 15% benefit the York Review found,
based on averaging a mere handful of grade B longitudinal studies.
9. Recent studies show that Cavities do not increase when fluoridation
stops. Mullen does not discuss this thorny problem for fluoridation
promoters.
10. Dental crises are being reported in countries (e.g Australia) and cities
(e.g. Pittsburg, Boston, NYC, Cleveland, Cincinnati) which have been
fluoridated for over 20 years. Mullen does not address this problem.

Clearly there are some major omissions in Mullen’s analysis. What about the
evidence he does cite, how convincing is that?

He begins his case by citing the anecdotal observations of McKay and others
in the early 20th Century that there appeared to be less tooth decay in
children with mottling and discoloration of their teeth, a condition which
we now call dental fluorosis. He then goes on to cite H. Trendley Dean’s
work:

> “In a series of classic shoe-leather epidemiological investigations,
> culminating in his famous “21-City Study”, Dean established that mottling of
> the teeth was extremely rare at fluoride levels of 1ppm or below, while the
> greater part of the caries preventive effect was to be seen at 1ppm. Dean
> published the results of his work in 1942.”

What Mullen doesn’t discuss was why Dean limited his famous study to only 21
cities when he had data from many other towns and cities. Nor does he
discuss the work of Rudolf Ziegelbecker from Austria who plotted ALL the
tooth decay data he could find from both America and Europe (including
Dean’s 21 data points), against the level of fluoride in the water and found
no relationship. However, when he plotted all the dental fluorosis figures
he could find against the level of fluoride in the water he found a very
strong relationship – as fluoride level went up, dental fluorosis went up.
Thus one of Dean’s findings was robust (the relationship between fluoride
levels and dental fluorosis) and one was not (the inverse relationship
between fluoride levels and tooth decay). See Ziegelbecker R. (1981),
Fluoride, 14, 123-7,.
Ziegelbecker used this analysis very effectively to persuade a number of
European countries NOT to fluoridate their water.

However, Mullen uses the Dean study and another study from the UK to
conclude that, “Water naturally fluoridated at 1 ppm clearly benefited
dental health” (my emphasis).

Mullen continues his case by moving onto to discuss the first trials of
artificial fluoridation in North America conducted in Grand Rapids,
Michigan; Newburg, NY; Brantford, Ontario and Evanston, Illinois. But he
makes no mention of the fact that the methodologies used in these early
trials were very poor by modern standards. The late Dr. Philip Sutton from
Melbourne, Australia, wrote several monographs and eventually a whole book
on the limitations of these studies ( Sutton P. (1996). The Greatest Fraud:
Fluoridation. Lorne, Australia: Kurunda Pty, Ltd.). Mullen makes no
reference to Sutton’s criticisms or to those of Dr. Hubert Arnold, a
statistician teaching at the University of California at Davis. Arnold
wrote:

> “The announced opinions and published papers favoring mechanical fluoridation
> of public drinking water are especially rich in fallacies, improper design,
> invalid use of statistical methods, omissions of contrary data, and just plain
> muddleheadedness and hebetude. Many of the blunders were so glaring that I
> gave them to my beginning freshman classes in statistics at the very first
> meeting. The students see through them straightway, and are afforded great
> amusement. Uproarious laughter frequently ensues. No special statistical
> equipment is necessary to detect those peccancies. Of course the class and the
> Group soon tired of those infantilities, and sought and found greater
> challenge.” (Arnold HA. (1980). Letter to Dr. Ernest Newbrun. May 28, 1980.
> http://www.fluoridealert.org/uc-davis.htm)

Mullen also mentions the Tiel-Culemborg study in the Netherlands (1953 -
1969) and the Hastings study in New Zealand (1954 - 1970). Both of these
studies have also been heavily criticized. A summary of criticism of the
Tiel-Culemburg has been revisited by Moolenburgh in the current issue of
Fluoride, 40(1), 75-76 (available online at
http://www.FluorideResaerch.org).

Even more flagrant abuse occurred in the Hastings study from New Zealand,
where the control city (Napier) was dropped after two years! The late Dr.
John Colquhoun studied the Hastings results very carefully and found that
the authors secured the supposed reduction in tooth decay in Hastings by
changing the criteria used for defining tooth decay half way through their
study, WITHOUT informing readers that this change had been made! (Colquhoun
J, Mann R. The Hastings fluoridation experiment: Science or swindle?
Ecologist 16 (6) 243-248 1986 17 (2) 125-126 1987; Colquhoun J. Flawed
foundation: A re-examination of the scientific basis for a dental benefit
from fluoridation. Community Health Studies 14 288-296 1990, and Colquhoun
J. (1997) Why I changed my mind about Fluoridation. Perspectives in Biology
and Medicine 41: 29-44. http://www.fluoride-journal.com/98-31-2/312103.htm)

Mullen also mentions studies from the UK. Watford, Kilmarnock and part of
Anglesey were fluoridated in 1955 and the controls were Sutton, Ayr and the
remaining part of Anglesey. Mullen claims that studies carried out after 5
years of fluoridation demonstrated much lower caries levels in the
fluoridated areas in 5-year old children. However, after 5 years, no
permanent teeth would have erupted, and so at best these results only
indicated impacts on the primary teeth, an issue made complicated by the
possibility that fluoride delays eruption of the teeth. Mullen does not
discuss this issue.

Referring to the Irish experience Mullen states that “Local, regional and
national studies carried out in the decades since have all confirmed that
children and adults living in fluoridated areas in Ireland have
significantly fewer decayed teeth” but he cites only one recent study to
support this claim.

Mullen’s case seems to rest almost entirely on this recent study which
compared decay rates on both side of the Irish border. For this Mullen
claims that decay rates in Northern Ireland (unfluoridated) are of the order
of 50% higher than in the Republic (fluoridated)” and buttressed this by
stating that “Decay rates had been similar prior to the introduction of
water fluoridation.” However, if he is going to rest his case largely on
this single study, it is regrettable that he did not provide the absolute
figures, rather than the often misleading percentage difference. For
example, the Brunelle and Carlos study claimed an 18% reduction, but that
only amounted to a saving of 0.6 of one tooth surface out of about 100 tooth
surfaces in a child’s mouth! This Irish study also needs to be examined very
closely to see how well the authors controlled for parental income, because
this factor has a far greater influence on tooth decay than fluoride levels
in the water. If this factor is not controlled extremely well you can get
any result you want!

In short, as far as demonstrating effectiveness this well known promoter of
fluoridation has done little more than cite a self-serving selection of
studies, most of them very old with very weak methodologies, rather than
providing a balanced view of the literature. He has also failed to tackle
some of the very thorny problems confronting the hypothesis that ingesting
fluoride reduces tooth decay. For example, he fails to address:

1. the issue of the mechanism of action being largely topical not systemic
2. the impact of delayed eruption of teeth muddling the comparison between
fluoridated and non-fluoridated communities
3. the fact that several modern studies have failed to detect an increase in
tooth decay when fluoridation has been halted
4. the fact that dental crises are being reported in cities and states in
the US which have been fluoridated for over 20 years, and
5. why after 60 years of research on this matter there has yet to be a
double blind random-control study demonstrating effectiveness.

If this was a journalist writing in a popular newspaper Mullen might be
forgiven, but for a professional writing a serious academic analysis in a
major dental journal, his analysis was inexcusably one sided and sloppy. It
is also hard to believe that Mullen has removed himself so much from the
literature of his opponents that he was unaware of the serious criticisms of
the studies he cites. Mullen didn’t have to agree with the criticisms of the
reports he cites but in an academic journal he was obliged to make readers
aware of their existence.

In part 2, I will examine Dr. Mullen’s evidence for the safety of
fluoridation.

Paul Connett
————————————————–
British Dental Journal (2005)

History of Water Fluoridation

Dr Joe Mullen

Introduction

Water fluoridation has been described by the Centre for Disease Control as
one of the ten most important public health advances of the 20th Century
(1). In this brief paper, I will describe the history of water fluoridation
and discuss the value of this policy in the early years of the 21st
Century.

Natural water fluoridation

The story of fluoridation begins with a mystery staining of the teeth
first described by dentist Dr. Frederick McKay in Colorado in 1901 (2) and,
independently in Naples in 1902 by Dr. J.M. Eager, an American dentist
stationed in Italy. Over the following years, McKay became aware of several
cases that suggested that the water supply might be responsible for the
staining. He also noted that decay rates were much lower in areas with
endemic dental staining than they were in other adjacent areas.

In the United Kingdom, an Essex dentist Mr. Norman Ainsworth had found
dental staining similar to McKay’s description of “Rocky Mountain Mottled
Teeth”. As part of a study for the Medical Research Council in 1925,
Ainsworth examined over 4,000 children and, for the first time, produced a
statistical comparison of decay rates between populations with the staining
and those without. This study showed that those living in areas where
mottled teeth were commonest tended to have much less dental decay. A
chemist with ALCOA (the Aluminium Company of America), H.V. Churchill,
became involved in the story in 1931. ALCOA was concerned that there was a
possibility that there was a link between this staining and the presence of
aluminium in drinking water. The staining had appeared in the town of
Bauxite, Arkansas, where ALCOA mined most of their aluminium. Churchill
analysed water from several areas where the staining was endemic for
unusual element concentrations and found the one common factor to all sites
to be elevated levels of fluoride. The supply in Bauxite itself was measured
at 13.7 ppm (parts per million).

Ainsworth was aware of Churchill’s research and decided to compare the
water supplies from the endemic staining area around Maldon in Essex with
that of the nearby town of Witham. The Witham water proved to have 0.5 ppm
fluoride, the samples from around Maldon ranged from 4.5 to 5.5 ppm. It
seemed clear that fluoride levels in water were related to both the staining
of the teeth and reduced decay levels. The US Public Health Service was
anxious to investigate this relationship and appointed a dentist, Dr. H.T.
Dean, to carry out the research. In a series of classic shoe-leather
epidemiological investigations, culminating in his famous “21-City Study”,
Dean established that mottling of the teeth was extremely rare at fluoride
levels of 1ppm or below, while the greater part of the caries preventive
effect was to be seen at 1ppm. Dean published the results of his work in
1942.

During the Second World War, children from South Shields, an industrial
town on the river Tyne in north eastern England, were evacuated to the Lake
District. The Senior School Dentist for Westmoreland noted that the
evacuees had far better teeth than local children. Robert Weaver, a dentist
working for the Ministry for Education, was aware of the work being carried
out in America and had the fluorine content of South Shields water
analysed. It proved to be around 1.4 ppm, much higher than is present in
most water supplies. He had North Shields (on the other bank of the Tyne)
water analysed; this proved to have a fluoride content of 0.25 ppm.

In 1944 Weaver examined 1,000 children on either side of the Tyne. This
study demonstrated much lower decay rates in both permanent and deciduous
teeth in South Shields. This study was the first to describe the effects on
the primary dentition.

There are many areas in England which today have significant natural
fluoride content in drinking water. These include Norwich, Ipswich,
Cambridge, Hartlepool, Slough, Bath, Swindon, Colchester and other sites
particularly in the counties of Essex, Norfolk, Suffolk, Durham,
Shropshire, Wiltshire and in North East London.The history of artificial
water fluoridation

Water naturally fluoridated at 1ppm clearly benefited dental health.
Following Dean’s studies, the health authorities in the United States
sought to reproduce this effect in low-fluoride areas by adding fluoride.
No obvious negative health effects had been noted in populations served by
naturally fluoridated water. A number of tests or pilot schemes were set up
to see whether the idea could work in practice.

On 25th January 1945, Grand Rapids, Michigan, became the first town in the
world to be artificially fluoridated. The previous year, a baseline study
comparing Grand Rapids with the neighbouring town of Muskegon had found
similar decay levels in deciduous and permanent teeth in both areas. Six
years later, surveys indicated that decay levels in 6 year-old children
(i.e. those born since fluoridation commenced) in Grand Rapids was almost
half of that of Muskegon. In July 1951, city officials in Muskegon decided
to fluoridate that town’s water supply. Other pilot schemes in the USA were
those in Newburgh, New York, which started fluoridating in May 1945, and
Evanston, Illinois, which began fluoridating in January 1946.

As with the Grand Rapids scheme, these towns were paired with nearby
“control” towns (Kingston, New York and Oak Park, Illinois) in order to
measure the effectiveness of the fluoridation scheme. In both cases,
significant reduction in dental decay rates were described in the
fluoridating towns, with little or no change in the controls. Several
important studies carried out outside of the USA in the early days include
the Brantford-Sarnia-Stratford study in Canada (1945-1962), the
Tiel-Culemborg study in the Netherlands (1953- 1969) and the Hastings study
in New Zealand (1954 - 1970). As in the case of the American studies,
significant reductions in decay experience were reported in artificially
fluoridated areas.

The Department of Health in the United Kingdom became interested in this
work. Three sites were selected for the initial fluoridation schemes in
1955; Watford, Kilmarnock and part of Anglesey. The areas selected as
controls were Sutton, Ayr and the remaining part of Anglesey. Studies
carried out after 5 years of fluoridation demonstrated much lower caries
levels in the fluoridated areas in 5-year old children. In the Republic of
Ireland, the Fluoridation of Water Supplies Act 1960 allowed for the
fluoridation of all public water supplies. The two major cities of Dublin
and Cork eventually commenced fluoridation in 1964, following the rejection
by the Supreme Court of a constitutional challenge to the 1960 Act. Local,
regional and national studies carried out in the decades since have all
confirmed that children and adults living in fluoridated areas in Ireland
have significantly fewer decayed teeth.

Currently, some 40 countries have artificial water fluoridation schemes in
existence. In some cases, only a small proportion of the population is
covered by the schemes. Most recently published estimates of population
coverage include (3): USA (64%), Canada (43%), Panama (18%), Republic of
Ireland (73%), Australia (61%), New Zealand (61%), Israel (75%), Malaysia
(70%), United Kingdom (10%), Singapore (100%), Brazil (41%), Argentina
(21%), Chile (40%), Spain (10%), Columbia (80%). Hong Kong is also
fluoridated, with 100% population coverage. Recently there have been major
extensions announced in the USA (particularly California) and
Brazil.Effectiveness of water fluoridation

The early studies reported reductions in decay experience of the order of
50% or more. That was at a time when fluoridated water offered the only
significant source of fluoride. The introduction of fluoridated toothpaste
in the early 1970s has provided a very important source of fluoride and
this is thought to have been a major contributor to the fall in decay rates
experienced in OECD countries in the past decades. Thus the relative
effectiveness of water fluoridation has fallen in recent years since the
absolute decay values in non-fluoridated areas has fallen. While we still
see relative disease reduction of 50%, the absolute value of this 50% has
decreased. Nonetheless, in the opinion of the public health professionals
involved, the value of the additional decay reduction brought about by
fluoridation is more than significant enough to warrant the continuation of
the policy.

An interesting recent study compared decay rates on both sides of the Irish
border (4). Northern Ireland provides an excellent control population for
the Republic; caries risk is similar, it has no fluoridation schemes and
the possibility of diffusion effects (the “Halo Effect”) is likely to be
low. The Halo Effect is a significant confounding factor; it occurs where
there is a significant population movement between the two areas under
study or where there is a significant movement of food or drink products
manufactured in fluoridated areas into the control area. This effect can
produce a serious underestimation of the true effectiveness of water
fluoridation. The aforementioned study showed that decay rates in Northern
Ireland are of the order of 50% higher than in the Republic. Decay rates
had been similar prior to the introduction of water fluoridation. This
difference exists in spite of the fact that fluoride toothpaste usage
appears to be higher in Northern Ireland.

Safety of water fluoridation

The question of the safety of water fluoridation has been investigated
time and time again by a variety of national and international commissions,
most notably in recent times by the NHS Centre for Reviews and Dissemination
in 2000 (the York Review) (5). This was a Systematic Review - which means
that all relevant studies in all languages and in all publications were
searched for and critically evaluated using validated guidelines. Over
3,000 studies relevant to dental and general effects of water fluoridation
on humans were identified. York’s main conclusion was that there was no
clear evidence of any adverse effect from water fluoridation other than
staining of enamel (dental fluorosis).

The York Review has been followed up in the United Kingdom by the Medical
Research Council (MRC) in 2004 (6). The MRC’s view is that there is very
little cause for concern on any potential general health issue in relation
to water fluoridation.

In Ireland, the York Review was reviewed by the Forum on Fluoridation,
which also interviewed some of the key personnel involved in the systematic
review. The Forum drew similar conclusions to those of the York team.

Allegations have been made that water fluoridation is linked to almost
every conceivable condition known to medicine - and some conditions beyond.
The range of allegations covers such diverse items as cancer, Alzheimer’s
disease, effects on salmon spawning, and even increasing crime rates in
American cities. The fact that none of these have so far been found to have
any substance should not be surprising; there are populations that have
been drinking naturally fluoridated water at around 1ppm for centuries for
whom no obvious adverse effects have been demonstrated.

Recent studies have supported the proposition that there is no chemical or
biological difference between naturally and artificially fluoridated water7
,8
. Water
fluoridation is supported by the World Health Organisation (WHO), which
recommends water fluoridation where it is politically and technically
feasible. Where water fluoridation is not possible, the WHO recommends salt
fluoridation as a next-best option.

Dental fluorosis

It has always been known that water fluoridation would be associated with
low levels of enamel discolouration. Dean’s studies predicted that very
mild enamel fluorosis would affect a small proportion of a fluoridated
population. The judgement call has always been that a low level of
fluorosis is well worth the large reduction in dental decay brought about
by fluoridation. Dental fluorosis is still often measured on Dean’s Index,
which has six points corresponding to No, Questionable, Very Mild, Mild,
Moderate and Severe Fluorosis. In Ireland, with over 70% of the population
served by fluoridated water, 80% of the population has either No Fluorosis
or Questionable Fluorosis, and perhaps 7% have fluorosis of aesthetic
concern (i.e. Mild and higher).

The treatment of dental fluorosis is essentially very simple. Most of the
staining is confined to the outer 50-100μm of enamel, and can actually be
abraded away using pumice and acid-etch gel. The technique I have used is
to etch the tooth surface using the gel and then pumice for 5-10 seconds,
repeating 10 times or so until the stain decreases. I find it is usually a
good idea to start with the second premolar to see if the colour improves,
as the staining may not actually be due to fluorosis, in which case the
treatment may have little effect - remember that there are approximately 90
different known causes of enamel defects. A rubber dam should be used. In
contrast with tooth decay, fluorosis does not cause abscesses, does not
cause pain and can be treated without use of any anaesthetics, either local
or general. There is no doubt that the level of fluorosis has increased in
the Republic of Ireland over the past 20 years, even if the overall level
of objectionable fluorosis is low. This increase has been thought to be due
largely to the inappropriate swallowing of toothpaste by young children.

Other forms of community fluoridation

Several other methods have been evaluated for providing community water
fluoridation. Fluoridated salt is used quite successfully and widely in
Europe and South America in particular. In situations where all salt in the
economy is fluoridated, including that used in food production, its
effectiveness comes close to that of water fluoridation. However, where
fluoridated salt is simply provided on sale along with unfluoridated salt,
its effectiveness on a population basis is quite limited.

Fluoridated rinses have been provided in many countries. The effectiveness
during school years is almost as good as water fluoridation but the effect
is a temporary one; once children leave the rinsing scheme, their decay
rates tend to approximate to the general non-fluoridated population. In
addition, there can be compliance problems within schools9
. Milk
fluoridation schemes have been pioneered most notably in the United Kingdom
and in Chile. In the Manchester area, the Borrow scheme was set up to
provide fluoridated milk to primary school children. In Chile, fluoridated
milk is provided through the health service rather than through schools.
This method of fluoridation is quite promising but, while beneficial, the
effect does not yet appear to be as strong as for water fluoridation. A
major method of fluoridation is, of course, the use of fluoridated
toothpastes. It is estimated that in excess of 95% of toothpaste sales in
Western Europe are of the fluoridated products.

Recommended use of fluorides

Guidelines on the correct use of fluorides will need to vary not only
between countries, but also between localities and even at the individual
level. This is obvious since the decay risk will vary in this way too. For
example, we can state that, based on diet and lifestyle surveys,
inhabitants of Scotland and the entire island of Ireland have significantly
higher decay risk than the inhabitants of the Nordic countries and England.

Surveys have shown that persons on low income have substantially higher
decay risk than others; and since there are regional variations in income
within all countries, it is likely that these regional variations will show
up as regions of higher decay risk too. Thus the relatively prosperous
South of England tends to produce lower decay scores than the historically
poorer North.

On the individual level, dental and medical considerations must be taken
into account. An individual with a very high decay risk may require extra
assistance from fluoride. Certain medical conditions can expose a person to
unusually high risks of morbidity or mortality from dental infections or,
more often, from the treatment of the dental problem; appropriate fluoride
supplementation can have enormous immediate benefits for the general health
of such individuals. A number of bodies have published recommendations on
the use of fluoride products and supplements. With the foregoing comments
in mind, I wish to pay particular note to those of the European Association
for Paediatric Dentistry (EAPD) of 200010
, and
the Forum on Fluoridation in Ireland (Forum) of 200211
. Both
guidelines agree on certain basics, such as the value of water
fluoridation, fluoride mouth rinses and professionally applied fluoride
varnishes. Where there is significant variation between these
recommendations concerns the appropriate use of fluoride supplements and
fluoride toothpastes.

The Forum recommendations were specific to the situation in the Republic of
Ireland only and were constructed mainly to provide broad information to
the public. Thus the main messages were kept clear and simple. These are
(a) do not use toothpaste for children under 2; (b) for children 2 to 7,
tooth brushing should be supervised and that a pea-sized amount of
adult-strength toothpaste is to be used. There was an important caveat -
the above recommendations were general and could be set aside by the
dentist if a high caries risk was detected. Child dental health indicators
in Ireland are among the best in Europe; for 5-year olds the decay index is
the lowest in Europe while for 12-year olds, it is 4th lowest - in spite of
the highly cariogenic dietary habits of Irish children. Since decay levels
at 5 years of age are low, we can conclude that decay risk for those under
2 years of age is generally very low. The Forum recommends that children
under 2 years of age have their teeth brushed with a toothbrush and tap
water only - no toothpaste of any kind is advised. Paediatric low fluoride
toothpastes (those at 500ppm or lower) were not recommended by the Forum as
it considered that the current evidence base was insufficient at present to
support their use.

Since most of Ireland is fluoridated and there is likely to be a
significant Halo Effect, fluoride supplementation was not recommended by
the Forum except in high risk individual cases. The EAPD recommendations do
include the use of supplementation as follows: “Recommended dosages of
fluoride supplements6 months to 3 years of age:

One 0.25 mg lozenge as a single dose per day (when water supplies have
less than 0.3 ppmF). Lozenges are to be preferred, but drops or soluble
tablets may be recommended for children unable to suck lozenges.3 to 6 years
of age:

One 0.25 mg lozenge twice a day (2×0.25 mg/day).Over 6 years of age:

One 0.50 mg lozenge twice a day (2×0.50 mg/day). In order to obtain a local
effect of fluorides from fluoride lozenges and the use of fluoride
dentifrice, the lozenges should be taken at different times of the day than
when tooth brushing. Children should be encouraged to allow the lozenges to
dissolve slowly in different sites in the mouth.” On the question of
toothpastes, the EAPD recommendations differ from those of the Forum in the
proposal that children under 2 have their teeth cleaned by smearing a very
small amount of low fluoride (<500ppm) toothpaste on the teeth while those
under 6 years of age brush using use low fluoride toothpastes. As one can
see, slightly different sets of reputable guidelines may exist. So which
one should the dentist use? As a general principle, each dentist should
seek to balance the relative risks of dental decay and enamel fluorosis
when giving advice on the dental care of children under 7 years of age.
While general guidelines are valuable in providing information to the
dentist, I would recommend that, where possible, local expert advice be
sought. The Community Dental Service in any country is likely to be a good
source of information on factors such as local decay patterns and local
water fluoride levels; it may be able to supply a set of guidelines
suitable to that particular locality.

Conclusion: the future of water fluoridation

Up to 1982, the only major cities to be fluoridated in the United Kingdom
were Birmingham and Newcastle. In 1985, the government of the day passed a
new fluoridation act which had the unforeseen effect of passing the right
to fluoridate water supplies to the shareholders of the newly privatised
water companies. Since 1985, in spite of requests from a number of health
authorities, no new water fluoridation schemes came into existence.
However, new legislation enacted at the end of 2003 has returned the
decision-making function to the public authorities. Under the terms of that
Act, a health authority wishing to fluoridate public water supplies must
hold a public consultation exercise and take its outcome into consideration
before proceeding with any new fluoridation scheme.

Fluoridation continues to provide a valuable public health benefit.
However, like any preventive measure, it only makes sense where there
exists a significant disease risk. The time may come in a particular
society where the decay risk is too small to continue fluoridating or to
consider starting. Such has been the case in Finland, where one town,
Kuiopo, had been fluoridated for decades and has now terminated the scheme.
In that situation, the caries risk was very low and the school dental
service provided significant school-based fluoride programmes. Such was
also the case in Basle, Switzerland, where water fluoridation was no longer
deemed necessary due to the new availability of fluoridated salt. Such will
certainly be the case in the most of the South of England, where decay risk
is now too low to gain any significant benefit from fluoridation. There are
areas where fluoridation could greatly benefit populations in Britain.

In my view, fluoridation could be well worth considering at least in the
North West of England and parts of Scotland. For example, Birmingham is
fluoridated, Manchester is not. The dental health of Birmingham children is
among the best in the United Kingdom while that of some Manchester children
among the worst. This inevitably translates into greater misery, pain and
increased recourse to general anaesthetic extractions in the high caries
area.

Currently, it is estimated that 400 million people have access to
fluoridated water worldwide and that this number is increasing.
Fluoridation has been shown to be remarkably safe and effective means of
reducing risk of the commonest disease in the western world. As long as the
risk of dental caries remains significant, water fluoridation remains a
public policy of great merit.

1 MMWR Weekly48(12) 241–243 Centre for Disease Control (US).
2 The bulk of this material is taken from Murray JJ and Rugg-Gunn A
Fluorides and Caries Prevention London:Wright 1982.
3 One In A Million. London:British Fluoridation Society 2004.
4 Whelton H, Crowley E, O’Mullane D, Cronin M, Kelleher V. North-South
Survey of Children’s Oral Health 2002. Cork: Oral Health Services Research
Centre, University College Cork 2003.
5 McDonagh MS, Whiting PF, Wilson PM, Sutton AJ, Chestnut I, Cooper J. et
al A Systematic Review of Public Water Fluoridation. York: NHS Centre for
Reviews and Dissemination, University of York 2000.
6 Water Fluoridation and Health. London: Medical Research Council 2002.
7 Maguire A, Moynihan PJ, Zohouri V. Bioavailability of fluoride in
drinking water – a human experimental study. Department of Health (UK)
2004.
8 Jackson PJ, Harvey PW, Young WF. Chemistry and Bioavailability aspects
of fluoride in drinking water. Water Research Council report CO 5037 2002.
9 Use of Fluorides in Oral Health Promotion in Ireland. Dublin:Department
of Health and Children 2005.
10 Oulis CJ, Raadal M, Martens L. Guidelines on the use of fluoride in
children. European Academy of Paediatric Dentistry 2000.
11 Report of the Forum on Fluoridation Dublin:Government Publications
2002.