Poster presentations: ORCA 2008, Groningen, The Netherlands
A number of poster presentations resulting from studies supported by the Foundation
were made at the 55th Annual ORCA congress, June 2008 in Groningen, The Netherlands.
The abstracts have been published in the Journal of the European Organisation for Caries Research. Caries Research, (2008) 42(3): 185 - 235.
"Fluoride Concentrations of Soft Drinks Available in
the Iranian Market".
S. Mortazavi (a), V. Zohoori (b), A. Maguire (c)
(a) Isfahan University of Medical Sciences , Iran;
(b) University of Teesside, (c) Newcastle University, UK
Parallel with the increasing amount of industrial production
of food and drink, the risk of fluoride exposure from this source
in nonfluoridated areas has increased. The aim was to compare
the fluoride concentrations of different types of ready-made
drinks available in the Iranian market, with the fluoride concentration
in tap drinking water in the city of Isfahan, central Iran.
As part of an investigation into fluoride intake and excretion in
Iranian children, the most popular drinks were identified and
categorized into 5 groups. Several different brands of each group
were purchased randomly from scattered areas of the city. Home
tap water samples were collected randomly from different areas
of Isfahan. In total, fluoride concentration was measured in triplicate
for 200 drink and 120 home tap water samples. The fluoride
concentration of non-milk-based drink samples was measured
directly using fluoride-ion-selective electrode. The hexamethyldisiloxane diffusion method was used to measure the fluoride
concentration of milk-based samples. The drink samples were
compared on the basis of fluoride concentration and the area of
manufacture. The mean fluoride concentration ( ± SD) of drinks
was 0.15 ± 0.12 mg/l with a range from <0.02 to 0.75 mg/l. The
values for tap water were 0.10 ± 0.006 mg/l. The mean fluoride
concentration of noncarbonated juices (0.24 ± 0.15 mg/l) was the
highest amongst the groups of drinks tested. More than 85% of
the brands purchased had been produced and transferred from
distant areas to the city. In conclusion, although both mean concentrations of fluoride in drink and tap water samples were less
than 0.2 mg/l, the wide range of fluoride concentrations and variety
of water sources of all drinks should be considered in community
fluoride studies.
"The Impact of Fluoridated Milks on the Availability
of Trace Elements in Milk".
A. Maguire (a), F.V. Zohoori (b), C.J. Seal (a), P.J. Moynihan (a), I.N. Steen (a)
(a) University of Teesside, Middlesborough, (b) Newcastle University, Newcastle-upon-Tyne, UK
Milk is a nutritious food, and a vehicle for fluoride administration. However, the impact of added fluoride on the nutritional profile of milk is unknown. Therefore, the effects of added fluoride in cow’s milk with varying fat contents, on trace element(Fe,
Zn, Cu, Cr, Mo and Se) availability in milk were investigated. An
in vitro method of simulated gastrointestinal digestion with enzymic
steps was designed to measure and compare the availability
of trace elements in pasteurised milk samples with 2 levels of
fat content – whole (4% fat) and skimmed (0.3% fat) milk – and 4
concentrations of fluoride dose – none, 0.5, 0.75 and 1.0 mg F/200
ml milk – as well as non-fluoridated and fluoridated (0.5 mg
F/200 ml) UHT 4% fat milks. Trace element concentrations were
measured by inductively coupled plasma mass spectroscopy.
Availability of each trace element in samples was calculated from
concentration in the supernatant in the digestion tube following
centrifugation, after each stage of digestion. The results showed a
negative effect of F on Cu availability. The mean (SD) concentration
of Cu in the supernatant from pasteurised 4% fat milk with
5 ppm F was 5.73 (1.87) and 6.11 (0.32) µg/100 g before digestion,
and after stomach, duodenal and jejunal digestion, respectively,
while for the equivalent non-fluoridated milk the mean concentrations
were 14.3 (3.17) and 11.1 (0.46) µg/100 g, respectively. Fat
removal increased the availability of Cu, Zn, Cr and Se, and decreased
the availability of Mo, while there was greater availability
of Cr from UHT milk compared with pasteurised samples. These
initial data suggest that adding F to milk does not have a marked
effect on its trace element profile with the exception of reduced
Cu availability.
"Dietary Fluoride Intake in British Children Aged
4–18 Years and Receiving Optimally Fluoridated
Water".
F.V. Zohoori (a), A. Maguire (b), C.L. Gannon (b), K. Tsoi (b), P.J. Moynihan (b)
(a) University of Teesside, Middlesborough, (b) Newcastle University,
Newcastle-upon-Tyne, UK
Knowledge of total dietary fluoride intake is important at a
population level for monitoring community fluoridation and at
an individual level for fluoride prescribing. The aim was to investigate the fluoride intake from non-alcoholic drinks including
water and starchy staple foods and baked goods in British
children aged 4 to 18 residing in fluoridated areas. Detailed
quantitative information on food/drink consumption came
from 1,659 individuals aged 4 to 18, who participated in the National
Diet and Nutrition Survey (NDNS) [Gregory et al., NDNS:
young people aged 4 to 18 years, 2000]; a nationally representative,
dietary survey conducted in 1997 in the UK. Fluoride concentration
values for each food/drink item consumed were derived
from the fluoride database developed by the School of Dental
Sciences, Newcastle University. Fluoride intake for each child
was calculated from fluoride concentration of each food/drink
and the amount consumed. The mean (SD) estimated dietary
fluoride intake from drinks and staple foods was 0.032 (0.018),
0.026 (0.014), 0.017 (0.011) and 0.017 (0.011) mg/kg bw/day for
4–6-, 7–10-, 11–14-, and 15–18-year-olds, respectively. Fluoride
intake from these dietary sources was less than the suggested
optimum level of total fluoride intake of 0.05–0.07 mg F/kg bw/
day in 94% of the children, while the intake of 2% of the children
exceeded this level. The results suggest that foods as well as
drinks are a considerable source of fluoride intake for some children
and therefore, studies monitoring total fluoride exposure
should consider dietary fluoride intake from all foods and
drinks.
"Effect of Varying Concentrations of Fluoridated Milk
on Enamel Remineralisation in vitro".
M. Malinowski, K.J. Toumba, S.M. Strafford, M.S. Duggal Paediatric Dentistry,
Leeds Dental Institute, UK
A decline in caries levels in children has been observed with the consumption
of fluoridated milk [Bian et al.: Comm Dent Oral Epidemiol 2003; 31: 241], but
there is still a need to find the optimum milk fluoride concentration for caries
prevention. A modified pH cycling model [Malinowski et al.: Caries Res 2007;
41: 278] was used to investigate changes in mineral concentration of sub-surface
caries-like lesions exposed to different concentrations of fluoride in milk.
An in vitro single blind experiment with 6 groups of 11 caries-like lesions
exposed to varying fluoride concentrations (0, 0.25, 0.5, 1.0, 5.0 and 10.0
ppm F) in milk was carried out. On each of the 14 days of the cycling period
the lesions were exposed to 5 2-min periods of cariogenic challenge (1.5 m M
CaCl 2 ; 0.9 m M KH 2 PO 4 ; 50 m M acetic acid, pH 4.8) and 2 5-min periods
in milk plus 10 min in a 1: 3 milk/saliva slurry. Throughout the cycling period
the slabs were stored at 37 ° C in artificial saliva and demineralisation/remineralisation
assessed by TMR using dedicated image software (Inspektor, Amsterdam). Remineralisation
(–Z; %vol · µm) was observed in all fluoride groups (0.25 ppm F, 121 ± 273;
0.5 ppm F, 139 ± 370; 1.0 ppm F, 268 ± 391; 5.0 ppm F, 483 ± 224; 10 ppm F,
517 ± 486) in contrast to demineralisation in the non-fluoride control (–201
± 75). Remineralisation was statistically significant for all concentrations
>1.0 ppm. The results showed that fluoride concentration in milk exhibits a
clear dose dependency in this model and that the presence of fluoride, even
at low concentrations, promotes remineralisation in a pH cycling model.
Chile: plans for expansion realised
The progress achieved in the milk fluoridation programme in Chile has been impressive.
It now reaches 3,600 rural schools in 9 regions of the country, with the total
number of participating children increasing to 235,000.
Water fluoridation plays a vital role in the prevention of dental disease in
Chile, but is only available to people living in urban or semi-urban areas.
The milk supplied to children in rural areas under the School Food Assistance
Program, operated by the Junta Nacional de Auxilio Escolar y Becas (JUNAEB),
therefore provides an excellent vehicle for the delivery of fluoride.
Milk fluoridation was first introduced to this country in 1994, with a pilot
project implemented in the rural community of Codegua, in the VIth region. The
positive results from the evaluation of this scheme led to development of a
programme in the 1Xth region and the subsequent expansion of milk fluoridation
in Chile. Interestingly, this is the only country which uses fluoridated powdered
milk products.. Another variation is in the fluoridating agent; disodium monofluorophosphate
is used as opposed to sodium fluoride in the other locations.
From the outset, the Instituto de Nutriçion y Tecnologia de los Alimenos
(INTA), Santiago, has been instrumental in the development of milk fluoridation
in Chile. It continues to play an important role with a commitment to further
research in this field and through the ongoing technical support provided to
JUNAEB.
Strategic review: priorities
As a result of a strategic review the trustees are further committed to the expansion
of the international programme and the continued development of community based
milk fluoridation schemes remain a priority.
The review highlighted that whilst the Foundation's mission has been achieved
over the past five years, the substantial increase in the number of children
consuming fluoridated milk has been wholly attributable to the extension of
existing programmes operating in five countries, with the extension of established
schemes and the implementation of new projects in other locations.
Although there remains scope to expand at existing sites, it is recognised
that the implementation of programmes in other countries is likely to be necessary
if the rate of growth is to be sustained. The trustees will therefore make the
necessary resources available to assist those interested in applying this method
of prevention, and more generally to promote the wider use of milk as a vehicle
for fluoride in those areas where it is not possible to use either water or
salt.
The Foundation will also continue to fund research designed to strengthen the
scientific base for milk fluoridation. In recent years our support of such studies
has been extended and the trustees have now resolved to make a further "Call
for Research" in 2009.
