Cochrane Oral Health Group (COHG) systematic review (2015)

Decay reductions in primary and permanent teeth

The results of a systematic review by the Cochrane Oral Health Group (COHG), published in June 2015, indicate that “water fluoridation is effective at reducing levels of tooth decay in children’s primary (baby) and permanent teeth”. (1)

Figures in its report show that, on average, children in areas that introduce water fluoridation have 35% fewer decayed, missing and filled primary teeth, and 26% fewer permanent teeth affected, than children in areas that do not adjust the naturally occurring fluoride level in their water supplies to the optimum level for healthy teeth.

More children with no experience of tooth decay

The review also found that, compared with non-fluoridated areas, fluoridated areas had 15% more children who had never experienced decay in their primary teeth, and 14% more children who had never experienced decay in their permanent teeth – a benefit which the authors describe as ‘substantial’ in its effect on oral health.

The Cochrane report’s authors note that public health interventions such as fluoridation can have greater impact on populations than those at the individual and clinical levels.

Adding to the existing evidence base

Their review adds to the previously existing evidence base established by five earlier systematic reviews conducted since 2000, all of which had identified significant dental benefits from this public health measure. (2) (3) (4) (5) (6).

Two of those earlier reviews (University of York, 2000 and Truman et al, 2002) were acknowledged in the Cochrane report as having documented the effectiveness of fluoridated water.

COHG authors also evaluated evidence for a US Preventive Services Task Force review, published in 2013, which recommends water fluoridation based on “strong evidence of effectiveness in reducing dental caries across populations”.

1. Iheozor-Ejiofor Z, Worthington HV, Walsh T, O’Malley L, Clarkson JE, Macey R, Alam R, Tugwell P, Welch V, Glenny A-M. Water fluoridation for the prevention of dental caries. Cochrane Database of Systematic Reviews 2015, Issue 6.

2. 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.

3. Truman BI, Gooch BF, Sulemana I, Gift HC, Horowitz AM et al (2002): Reviews of evidence on interventions to prevent dental caries, oral and pharyngeal cancers, and sports-related craniofacial injuries. American Journal of Preventive Medicine, 23: 21-54.

4. National Health and Medical Research Council (2007):  A systematic review of the efficacy and safety of fluoridation.  Australian Government.

5. Griffin SO, Regnier E, Griffin PM, Huntley V (2007): Effectiveness of fluoride in preventing caries in adults. Journal of Dental Research, 86: 410-415.

6. Centers for Disease Control and Prevention Community Preventive Services Task Force (2013): Community Water Fluoridation – Task Force Finding and Rationale Statement.

KEY FINDINGS

TOOTH DECAY DOWN
Average reduction of 35% in the
number of decayed, missing
and filled primary teeth per child
in fluoridated areas compared with
non-fluoridated ones

TOOTH DECAY DOWN
Average reduction of 26% in the
number of decayed, missing and
filled permanent teeth per child
in fluoridated areas compared with
non-fluoridated ones

MORE CHILDREN WITH
NO EXPERIENCE OF DECAY
Average increase of 15% in children
free from decay in their primary
teeth in fluoridated areas compared
with non-fluoridated ones

MORE CHILDREN WITH
NO EXPERIENCE OF DECAY
Average increase of 14% in children
free from decay in their permanent
teeth in fluoridated areas compared
with non-fluoridated ones