Fluorides and oral health

Fluorides and oral health is a designated research area in the School. Our work is centred on the current important issues in fluoride research including the implementation and safety of fluoride. We collaborate with national and international centres to support the World Health Organisation’s (WHO) international mandate and programme priorities.

Fluorides and oral health

In collaboration with nine international centres, we developed a gold standard method for measuring fluoride in biological and non-biological samples (1), which has been used by many researchers around the world. We measured the fluoride content of more than 500 commercially available foods and drinks used by babies and young children in the UK (2) and generated a unique fluoride database which can be used by epidemiologists and health researchers to estimate an individual’s fluoride intake and to investigate the relationships between intake and important health factors such as bone mineral density, fracture and osteoporosis.

From a public health perspective, it is very important to observe if a population receives sufficient exposure to fluoride. The WHO recommends monitoring of fluoride supplementation programmes to ensure that total fluoride ingestion from all sources is appropriate. We developed experimentally based models to allow estimation of total daily fluoride intake and retention by analysing urine (3).

This has resulted in the revised WHO guidelines for urinary fluoride excretion to monitor community preventive programmes; and Professor Vida Zohoori was on the WHO expert revision panel (4).

In collaboration with Newcastle University, we designed a study to provide a robust evidence base for consultants in dental public health and other health professionals to determine whether the amount of fluoride added to school milk should be changed. As a result of our study (5-7), the UK National Fluoridated Milk Group suggested that the amount should be increased from 0.5 mg F to 0.8 mg F. We were commissioned to assist Blackpool City Council, in 2015, to carry out a urinary fluoride excretion monitoring project to assess fluoride exposure of school children before making any decision on introducing fluoridated-milk schemes in the primary schools in Blackpool.

Complete collection of 24 hour urine samples, to monitor fluoride exposure in children, is difficult due to the associated logistical challenges. Following the WHO guidance, we have established reference values for the urinary fluoride/creatinine ratio (UF/Cr) in a single time point urine sample (8), which could facilitate fluoride exposure monitoring using spot urine samples as a simple and useful tool in epidemiological studies. This simplified approach could be valuable for public health authorities and policy makers when monitoring and/or implementing fluoride-based community prevention programmes for oral health as well as national surveys.

(1) Martinez-Mier et al, 2011

(2) Zohoori FV & Maguire A, 2016

(3) Villa et al, 2010

(4) WHO, 2014

(5) Maguire et al, 2013

(6) Zohoori et al, 2012

(7) Walls et al, 2012

(8) Zohoori FV & Maguire A, 2017