Fluoride research: changes to national and international policy and practice in dental health
Submitting InstitutionTeesside University
Unit of AssessmentAllied Health Professions, Dentistry, Nursing and Pharmacy
Summary Impact TypeHealth
Research Subject Area(s)
Medical and Health Sciences: Dentistry, Public Health and Health Services
Summary of the impact
According to the World Health Organization (WHO), 60% to 90% of school
children are affected by tooth decay in industrialised countries 1,2.
At low levels, fluoride can reduce tooth decay, but high levels can damage
developing tooth enamel in young children. Our research has informed
the revised WHO guidelines for monitoring community tooth decay
prevention programmes and the UK National Fluoridated Milk Advisory
Group's recommendation to increase the amount of fluoride added to
school milk. The WHO guidelines are accepted and implemented
internationally representing a substantial spread of influence. The
recommendation to increase the amount of fluoride in school milk UK-wide
is significant, as it will further control and reduce dental caries,
especially in deprived areas with non-fluoridated water supply. In
addition, we have established better measures of babies' and children's
actual and ideal fluoride intake, including better techniques to determine
the fluoride content of foods, a protocol for monitoring fluoride intake
through urinary excretion, and experimentally-based models to monitor
community preventive programmes.
- Peterson PE, Bourgeois D, Ogawa H, Estupinan-Day S, Ndiaye C. The
global burden of oral diseases and risk to oral health. Bulletin of the
World Health Organization 2005;83:661-669
- Peterson PE. Priorities for research for oral health in the 21st
century — the approach of the WHO global oral health programme.
Community Dental Health 2005; 22:71-74.
We, in collaboration with Newcastle University, have undertaken studies
focusing on the current important issues in fluoride research including
fluoride measurement and total exposure for maximum dental benefit while
minimising the risk of dental fluorosis. Our work is consistent with the
WHO's current Priority Action Area — Oral Health and Fluorides.
From 2003 to 2010, we collaborated with nine fluoride research centres to
develop and evaluate key standardised direct and indirect techniques for
determining the fluoride content of biological and non-biological samples
 and hence, accurately, the fluoride exposure of individuals. We and
other fluoride laboratories have successfully used these techniques to
measure fluoride contents of different samples at our laboratories. Zohoori
has been employed at Teesside University since May 2007; therefore all
work conducted after this date took place in the submitting unit. In
2008, Dr Zohoori led a project in which fluoride contents of more
than 180 commercially available foods and drinks used by babies and young
children in the UK were measured [2,3]. In 2009, Dr Vida Zohoori in
collaboration with Newcastle University developed a specific Standard
Operating Procedure (SOP) to measure fluoride content of milk. This
SOP has been used by one of the three dairies in the UK that produce
fluoridated milk to measure fluoride concentration as a routine check.
Mouthwashes are increasingly used as an adjunct to toothpastes in oral
hygiene regimes. In 2008, Dr Vida Zohoori led a project to test the
potential benefit of the combined use of a fluoridated toothpaste and a
fluoridated mouthwash. Our study  formed part of a position paper
in the British Dental Journal (Pitts et al., 2012:
which contained key recommendations for the use of such products, and has
also been cited by the British Dental Association: Available at: http://www.bda.org/students/help-advice/clinical/ortholist.aspx
In 2009, Dr Vida Zohoori collaborated with the Institute of Nutrition and
Food Technology, University of Chile; Antioquia University, Colombia; and
Newcastle University, UK to develop experimentally-based models in
order to estimate total daily fluoride intake and retention from urinary
fluoride excretion data . The data have been used to revise WHO
guidelines for urinary fluoride excretion to monitor community preventive
For many years and in many countries, fluoride has been added to milk as
a primary preventive and public health measure for caries control. In the
UK, milk fluoridation is used in a school-based programme for children at
high risk of caries, residing in low fluoridated water areas. These
schemes provide fluoride milk (containing 0.5 mg fluoride in a 189-ml
carton) on school days. However, it has been suggested that this amount of
fluoride might not achieve the best balance of dental protection and risk
of side-effects. In 2008 at Teesside, Dr Vida Zohoori was the
co-applicant of a study, commissioned by the UK National Fluoridated
Milk Advisory Group, which aimed to determine whether children
receiving fluoridated milks are sub-optimally exposed to fluoride based on
WHO guidelines for urinary fluoride excretion; and to provide a robust
evidence base to determine whether the amount of fluoride added to school
milk should be reviewed. This study concluded that both the existing
fluoride concentrations of 0.5 mg fluoride and the intervention project
dose of 0.9 mg fluoride in 189 ml milk may be too low to achieve WHO
recommended urinary fluoride excretions concomitant with optimal fluoride
exposure for children > 6y . Based on this study, the National
Fluoridated Milk Advisory Group decided, in May 2011, to recommend an
increase in the amount of fluoride added to a 189 ml carton of school milk
in the UK from 0.5 mg to 0.8 mg fluoride.
References to the research
(Citations from Scopus database)
 Martínez-Mier EA, Cury JA, Heilman JR, Katz BP, Levy SM, Li Y,
Maguire A, Margineda J, O'Mullane D, Phantumvanit P, Soto-Rojas AE,
Stookey GK, Villa A, Wefel JS, Whelton H, Whitford GM, Zero DT, Zhang W, Zohoori
V: Development of Gold Standard Ion-Selective Electrode-Based Methods for
Fluoride Analysis. Caries Research 2011; 45: 3-12.
Cited 10 times. Available in REF 2.
 Maguire A, Omid N, Abuhaloob L, Moynihan PJ, Zohoori FV.
Fluoride content of Ready-to-Feed (RTF) infant food and drinks in the UK.
Community Dentistry and Oral Epidemiology. 2012, 40(1):26-36.
Cited 2 times as well as in the following book chapter:
Nutrition in Infants: Risks and Management, R Sharma — Nutrition in
Infancy, 2013 — Springer http://link.springer.com/chapter/10.1007/978-1-62703-224-7_2#
 Zohoori FV, Moynihan PJ, Omid N, Abuhaloob L, Maguire A.
Impact of water fluoride concentration on the fluoride content of infant
foods and drinks requiring preparation with liquids before feeding. Community
Dentistry and Oral Epidemiology. 2012, 40:432-440.
Cited 3 times.
 Duckworth RM, Maguire A, Omid N, Steen IN, McCracken GI, Zohouri
FV. Effect of rinsing with mouthwashes after brushing with a fluoridated
toothpaste on salivary fluoride clearance. Caries Research. 2009,
43:391-396. Cited 10 times. Available in REF 2.
 Villa A; Anabalon M; Zohouri V.; Maguire A; Franco AM;
Rugg-Gunn A. Relationships between Fluoride Intake, Urinary Fluoride
Excretion and Fluoride Retention in Children and Adults: An Analysis of
Available Data. Caries Research. 2010, 44:60-68. Cited 10
times. Available in REF 2.
 Maguire A, Walls R, Steen N, Teasdale L, Landes D, Omid N, Moynihan
P, Zohoori FV. Urinary fluoride excretion in 6- to 7-year olds ingesting
milk containing 0.5 or 0.9 mg fluoride. Caries Research. 2013, 47:
291-298. Available in REF 2.
Details of the impact
The stated goal of WHO community-based public health programmes is to
implement the most appropriate means of maintaining a constant low level
of fluoride in as many mouths as possible. We have collaborated with
nine laboratories in five different countries on an international
project that aimed to develop a much needed gold standard method for
measuring fluoride in biological and non-biological samples (Martinez-Mier
et al., 2011). This was the basis for development of a Standard Operating
Procedure, in collaboration with Newcastle University, which has been
used by Fresh Pastures Dairy, Ossett (a).
Mouthwashes are increasingly used as an adjunct to toothpastes in oral
hygiene regimes. In 2009, we led a project, funded by Johnson &
Johnson, to test the potential benefit of the combined use of a
fluoridated toothpaste and a fluoridated mouthwash. The original
concern expressed by some was that 100 ppm fluoride in mouthwash would be
too low, but our study was the first one to show that it is sufficient to
maintain salivary fluoride levels, where this is a main concern for dental
professionals and the consumers. Our study (Duckworth et al., 2009) formed
part of a position paper in the British Dental Journal (b),
which contained key recommendations for the use of such products. Our
study has also been cited by the British Dental Association: "The value of
mouthwash to orthodontic patients" (c, d).
From a public health perspective, it is very important to observe if a
population receives optimal exposure to fluoride. WHO recommends that any
fluoride supplementation programmes should be monitored prior to and after
implementation to ensure that ingestion of fluoride from all sources by
the children involved is at the appropriate level. However, it is very
difficult to estimate total daily fluoride intake in children. We
developed experimentally-based models allowing the estimation of total
daily fluoride intake and retention from urinary fluoride excretion data
(Villa et al., 2010). WHO published a monitoring document in 1999
(Monitoring of Renal Fluoride Excretion in Community Preventive Programmes
on Oral Health), which has been a valuable key source to the WHO Global
Oral Health Programme. A formal review of the guidance was undertaken in
December 2011 at the WHO technical working group meeting to which Dr.
Vida Zohoori of the Health and Social Care Institute, as an
international expert in the use of fluoride for public health, was
invited (e). Our publication (Villa et al., 2010) has
been accepted as one of the bases for the revised WHO guidelines for
urinary fluoride excretion to monitor community preventive programmes.
Since only 10% of the UK population receive fluoridated water, a school
milk fluoridation scheme was introduced in 1993 as a public health measure
for caries control in non-fluoridated socially-deprived areas. Fluoride
milk schemes are offered by 510 education establishments in the UK
including more than 40,000 children aged between 3 and 11 years. Currently
a 189 ml carton of semi-skimmed milk containing 0.5 mg fluoride is the
standard daily dose in the UK. However, it is not clear that this delivers
the optimal amount of fluoride to balance dental protection against side
Dr Vida Zohoori, (alongside Dr Anne Maguire, a Professor of
Preventive Dentistry at the School of Dental Sciences, Newcastle
University) was commissioned by the UK National Fluoridated Milk
Advisory Group to investigate the urinary excretion of fluoride
associated with milk fluoridation. We designed and carried out a
study to provide a robust evidence base for dental public health
consultants and other health professionals to review the amount of
fluoride added to school milk. Our study did not show any statistically
significant differences in urinary fluoride excretion between the children
who received fluoridated milk containing 0.5 mg fluoride and those who
received fluoridated milk containing 0.9 mg fluoride. Our study also
suggested that the moderate effectiveness of 0.5 mg fluoride milk used in
the school milk programme could be due to the low fluoride dose in milk
and/or sub-optimal compliance with milk consumption in the children
participating in the scheme. Our study, therefore, concluded that actual
fluoride milk consumption should be assessed when the efficacy of UK
school milk schemes is being investigated or evaluated, particularly if
the fluoride dose is under review.
As a result of our study, the National Fluoridated Milk Advisory Group
decided in May 2011 that the amount of fluoride added to school milk in
the UK should be increased from 0.5 to 0.8 mg fluoride (f,g).
Approval for this increase has been obtained from all ten participating
local authorities and the change has taken effect since September 2013 (h).
(We appreciate that the date of the implementation falls outside the REF
impact census period, but it is included here to show the evidence
translation process in the round. The implementation could not have
occurred earlier, due to the school summer holiday period.)
Our study also showed that UK schemes should review their current
monitoring programme. As a result, in 2012 we (Dr Vida Zohoori, as the
co-author, alongside Dr Anne Maguire, a Professor of Preventive Dentistry
at the School of Dental Sciences, Newcastle University) developed a
protocol for baseline and ongoing monitoring of total fluoride intake and
urinary fluoride excretion in children participating in milk fluoridation
programmes in the UK. The National Fluoridated Milk Advisory Group's
monitoring group has now prepared a Standard Operating Procedure based
on the protocol we have developed.
Sources to corroborate the impact
(a) Director, Fresh Pastures CIC.
(e) Responsible Officer, Oral Health Chronic Disease and Health
Promotion. World Health Organization, Geneva.
(f) Specialist in Dental Public Health, Public Health England,
(g) Assistant Public Health Programme Manager. Knowsley Council,
Written factual statements supporting the impact claims have been
received from (e), (f), and (g), and are available on request.