http://www.holisticmed.com/fluoride/nobenefit.htmlFluoridated Water Does Not
Prevent Tooth Decay
by Mark D. Gold
I will cover two areas in this section. I will list a selection of information which shows that fluoridation is not helping to prevent dental decay. At the same time, I will comment on how the Dental Trade Organizations have used flawed studies to convince dentists that fluoridation was useful. I will preface those comments with:
"ALERT #x"
For this discussion, remember that in the U.S., Trade Organizations like the American Dental Association (ADA) recommend that water should be fluoridated to 1 part per million (1ppm), although they allow for variations depending upon the climate (.7 ppm - 1.2 ppm).
Also, please remember that the original studies by H. Trendly Dean on fluoridation which led to the decision to allow fluoridation of municipal water supplies
Were worthless by his own criteria.
Did not consider other minerals in the water.
Did not consider the differences between "natural fluoride" (e.g., CaF) and fluoride waste products (e.g., NaF).
Only reported his chosen selection of data -- a subsection of the data gathered.
Had little or no statistical analysis.
Included no safety experiments except for dental fluorosis.
Yiamouyiannis, J. "Water Fluoridation and Tooth Decay: Results From the 1986-1987 National Survey of U.S. Schoolchildren" Fluoride, Journal of The International Society for Fluoride Research (Volume 23, No. 2; April 1990; pp 55-67).
This study showed, once and for all, that fluoridation of the U.S. water supply was worthless, at best.
Summary: Data from dental examinations of 39,207 schoolchildren, aged 5-17, in 84 areas throughout the United States are analyzed. Of these areas, 27 had been fluoridated for 17 years of more (F), 30 had never been fluoridated (NF), and 27 had been only partially fluoridated or fluoridated for less than 17 years (PF). No statistically significant differences were found in the decay rates of permanent teeth or the percentages of decay-free children in the F, NF and PF areas. However, among 5-year-olds, the decay rates of the deciduous teeth were significantly lower in F than in NF areas.
Table 2
Average-age-adjusted DMFT [Decayed, Missing, Filled Teeth] rates for 39,207 U.S. schoolchildren and 17,336 lofe-long resident schoolchildren in 84 areas throughout the United States. Standard deviations are given in parentheses.
---------------- Total --------------- Life-Long --
Fluoridation
Status No. of
Areas No. of
Students DMFT No. of
Students DMFT
Fluoridated
27
12,747
1.96
(0.415)
6,272
1.97
(0.465)
Partially
Fluoridated
27
12,578
2.18
(0.465)
5,642
2.25
(0.470)
Nonfluoridated
30
13,882
1.99
(0.408)
5,422
2.05
(0.517)
As you can see, there are no statistical differences in decayed, mission, or filling teeth for U.S. children aged 5-17.
Yes, there is a stastically significant advantage in DMFT for 5-year-olds. However, by age 6, that advantage disappears. The suspected cause for the one-year, temporary benefit is slightly delayed tooth eruption in fluoridated water drinkers. Whatever the cause, remember, there are no statistically significant difference after age 5.
ALERT #1
Recently, Brunelle used the same data to "prove" a statistically significant advantage in dental decay in fluoridated sections of the U.S. ("Caries Attack in the Primary Dentition of U.S. Children" J. Dent. Research 69(Special Issue): 180 [Abstr. No. 575], 1990.) However, Brunelle used only one year (5-year-olds) of the data that was gathered in the national survey: 5 to 17 years old! As was mentioned above, this slight advantage in fluoridation disappears after age 5 and is likely caused by slightly delayed tooth eruption in 5-year-olds. By picking tiny subsections of data collected, a researcher can prove whatever he or she wants! This is not the only time this flawed data analysis technique was used in fluoridation research.
Also, this study points to the fact that other studies which relied to a large extent on 5-year-olds and few older children may also show skewed results.
ALERT #2
In another poor study, Brunelle and Carlos used more complete survey data to seemingly "prove" the advantages of fluoridation. ("Recent Trends in Dental Caries in U.S. Children and the Effect of Water Fluoridation" J. Dental Research, 69(Special Issue): 723-728, 1990). This time Brunelle used more data than above, but made many other sloppy errors as pointed out by Yiamouyiannis.
"It contains extremely serious errors. For example, by a cursory inspection, we found two values that are off by 100% or more. In their Table 9, the DMFS figure for life-long F exposure residents of Region VII should be about 3, not 1.46 as reported. Form their Table 3, the percent of 5-year-olds who have caries is 1.0%, not the 2.7% that can be calculated from the table. When I pointed out this error to Dr. Carlos he admitted that only 19 out of the 1851 5-year-olds had caries (19/1851 = 1%), but refused to make the correction."