The York review (2000) of water fluoridation studies found evidence to suggest that this public measure may help to reduce dental health inequalities that ordinarily divide children living in affluent communities from those in more socially deprived communities (1).

Combining the results of five studies of 5-year old children that had used the same method of classifying social class , the York analysis found that across all social classes the number of teeth affected by decay was lower in fluoridated than in non-fluoridated areas.  This was no surprise, as the benefits of fluoridated water in preventing tooth decay were already very well known.

What is particularly interesting about the York analysis (as can be seen from the graph on this page) is that the gap in dental health between children from the highest and lowest social groups is much narrower in fluoridated areas than in non-fluoridated areas.

The graph shows that in non-fluoridated areas (described here as ‘low fluoride’ areas) children from the lowest social groups had more than twice as many teeth affected by decay as those from the highest social groups.  By contrast, in fluoridated areas the difference was much smaller.

As the York reviewers concluded: “These data from 5-year old children suggest that water fluoridation is leading to a decrease in decayed, missing and filled teeth across the social classes and reducing the inequalities in dental health between the social classes.”

However, the York report flags up that this trend is not seen in other age groups.  The narrowing of the dental health gap may, it argues, be a finding peculiar to the younger age group.  Alternatively, it may be because only a very small number of studies of older age groups of children were reviewed by the York team.

1. McDonagh M, Whiting P, Bradley M, Cooper J, Sutton A, Chestnut I (2000): A systematic review of public water fluoridation. Centre for Reviews and Dissemination, University of York.