If you are new to fluoride in water, look here for an introduction

The format of this page is

  • A summary of the key points relevant up to 2020
  • An online and printable version of the 2012/3 publication “one in a million”
  • A summary of the main points raised by more recent papers and reports
  • Access to a list of the key papers and reports published since 2012/3
  • Access to an archive of other reports etc.

Key Points (Updated 2020)

  • There are some 90 different causes of markings on the enamel surfaces of teeth. These are known as ‘enamel defects’.
  • One of the 90 or so causes of enamel defects is called ‘dental fluorosis’.
  • In most cases, dental fluorosis appears as barely visible pearly white flecks on the surface of teeth and is undetectable except by an expert.
  • The more obvious, cosmetically unacceptable forms of dental fluorosis are rare in the UK.
  • The risk of dental fluorosis can be reduced if parents follow dentists’ advice on supervising how their children use fluoride toothpaste and on whether or not they should also be given fluoride supplements.
  • There has been an increase in mild and very mild dental fluorosis in the United States; so fluoride levels for the US have been reset at 0.7 ppm.

Evidence up until 2012/13 in One in a Million Database

Our One in a Million online database includes a comprehensive section on dental fluorosis. We would recommend reading the relevant chapter from “one in a million” which is a summary (including key evidence) of the issue as at 2013.


Dental fluorosis (updated 2013)

Full Chapter


Dental fluorosis - Printable

Summary of Data Published Post 2012/2013

  • The Cochrane systematic review of the international literature (Iheozor-Ejifor,2015) suggested that for all fluorosis the prevalence was 40% at 0.7 ppm fluoride as against 28% at 0.1 ppm. For fluorosis of aesthetic concern (Dean, mild to severe), the equivalent figures were 12% and 8%. The authors noted “that moderate fluorosis may be considered an unwanted effect rather than an adverse effect”. In addition, “mild dental fluorosis may not even be considered an unwanted effect”.
  • The most recent data for England were published by Pretty et al (2016) The authors assessed dental fluorosis using a standardised polarised white light image of the maxillary incisors and, in addition, interviewed the 11 to 14-year old children about their views on the aesthetics of their teeth. The authors concluded that “the levels of fluorosis that might be considered of aesthetic concern are low and stable and unlikely to represent a public health issue”.  Commenting on the report, PHE (2018) suggest continued monitoring seems justified.
  • In the United States an increase in the level of dental fluorosis of mainly mild or very mild degrees of severity was reported (DHSS, 2015). As a result, recommended fluoride levels for US community water fluoridation schemes were reset at 0.7 ppm. Further data have been published by Neurath et al (2019), although the increases reported in this paper have been dismissed as implausible (Kumar et al 2019; DHHS, 2019; AADR, 2019). The most recent data (2015-6) suggest 10.5% of 6-19- year-olds have dental fluorosis of aesthetic concern (DHHS, 2019).
  • Curtis et al (2020) reporting from the Iowa longitudinal study of dental fluorosis reported that “fluorosis severity, which was initially mild to moderate, declined during adolescence and young adulthood.” 
  • The American Association for Dental Research (AADR, 2019) calls for current research on new technologies for use in epidemiological and monitoring surveys to be accelerated.
  • Research has also focussed on other non-fluoride linked enamel defects including molar-incisor hypo-mineralization (MIH) (Schwendicke et al, 2018). MIH and similar defects can be confused with dental fluorosis. It has been suggested that a diagnosis/study of dental fluorosis might be improved by including an assessment of the risk factors for MIH. (Sabokseir et al, 2016).