© 2025 American Dental Association l 15
Fluoridation Facts
7. Is water fluoridation effective in helping to prevent tooth decay?
Answer
Yes. According to the best available scientific evidence, community water fluoridation is an
effective public health measure for preventing tooth decay in children, adolescents, and adults.
With hundreds of studies published in peer-reviewed scientific journals, fluoridation is one of the
most studied public health measures in history, and it continues to be studied today.
Fact
The effectiveness of fluoride in drinking water to prevent tooth decay has been documented in the
scientific literature for more than 80 years. Before the first community fluoridation program began
in 1945, epidemiologic data from the 1930s and 1940s were collected and analyzed.17,18,94 What
began as research to learn what caused “Colorado Brown Stain” (dental fluorosis) led to the discovery
of strikingly low tooth decay rates associated with fluoride in drinking water at approximately 1 ppm
(mg/L). Figure 2 shows the results of early research by Dr. H. Trendley Dean noting the association
among children’s experience with tooth decay (solid line), dental fluorosis (dotted line), and the
fluoride concentration in drinking water.18,94
Additional information on this topic can be found in the Introduction.
Figure 2. Dean’s Graph
Relationships of tooth decay
experience (solid line), dental
fluorosis index (dashed line) and
the fluoride concentration of
drinking water.28,29
Systematic Reviews and Meta-Analyses
Since that time, hundreds of studies have continued to show fluoride’s effectiveness in helping to
prevent tooth decay. Those individual studies have been included in a number of systematic reviews.
A systematic review is an analysis of studies that identifies and evaluates all the evidence with which to
answer a specific, narrowly focused question. It entails a methodical and unbiased review process that
locates, assesses, and combines high-quality evidence from a collection of scientific studies to obtain
a comprehensive, valid, and reliable review on a specific topic. Systematic reviews provide the highest
level of scientific evidence about a specific research question. The following is a summary of significant
reviews of community water fluoridation demonstrating that water fluoridation effectively reduces
tooth decay.
Fluoride Concentration in Water (ppm)
Caries
Experience
per
Child
Fluorosis
Index
Fluoridation Facts
7. Is water fluoridation effective in helping to prevent tooth decay?
Answer
Yes. According to the best available scientific evidence, community water fluoridation is an
effective public health measure for preventing tooth decay in children, adolescents, and adults.
With hundreds of studies published in peer-reviewed scientific journals, fluoridation is one of the
most studied public health measures in history, and it continues to be studied today.
Fact
The effectiveness of fluoride in drinking water to prevent tooth decay has been documented in the
scientific literature for more than 80 years. Before the first community fluoridation program began
in 1945, epidemiologic data from the 1930s and 1940s were collected and analyzed.17,18,94 What
began as research to learn what caused “Colorado Brown Stain” (dental fluorosis) led to the discovery
of strikingly low tooth decay rates associated with fluoride in drinking water at approximately 1 ppm
(mg/L). Figure 2 shows the results of early research by Dr. H. Trendley Dean noting the association
among children’s experience with tooth decay (solid line), dental fluorosis (dotted line), and the
fluoride concentration in drinking water.18,94
Additional information on this topic can be found in the Introduction.
Figure 2. Dean’s Graph
Relationships of tooth decay
experience (solid line), dental
fluorosis index (dashed line) and
the fluoride concentration of
drinking water.28,29
Systematic Reviews and Meta-Analyses
Since that time, hundreds of studies have continued to show fluoride’s effectiveness in helping to
prevent tooth decay. Those individual studies have been included in a number of systematic reviews.
A systematic review is an analysis of studies that identifies and evaluates all the evidence with which to
answer a specific, narrowly focused question. It entails a methodical and unbiased review process that
locates, assesses, and combines high-quality evidence from a collection of scientific studies to obtain
a comprehensive, valid, and reliable review on a specific topic. Systematic reviews provide the highest
level of scientific evidence about a specific research question. The following is a summary of significant
reviews of community water fluoridation demonstrating that water fluoridation effectively reduces
tooth decay.
Fluoride Concentration in Water (ppm)
Caries
Experience
per
Child
Fluorosis
Index
