Journal of the Canadian Dental Association.
(
3/93, p. 273.)

"In most areas of Canada, the prevalence of dental fluorosis probably ranges somewhere between 35 to 60 percent in fluoridated communities."
   

Classification and Criteria of Dental Fluorosis

Normal - The enamel represents the usual translucent semivitriform type of structure. The surface is smooth, glossy, and usually of a pale creamy white color.

Very Mild - Small, opaque, paper white areas scattered irregularly over the tooth but not involving as much as 25 percent of the tooth surface. Frequently included in this classification are teeth showing no more than about 1-2 mm of white opacity at the tip of the summit of the cusps of the bicuspids or second molars.

Mild - The white opaque areas in the enamel of the teeth are more extensive. but do not involve as much as 50 percent of the tooth.

Moderate - All enamel sufaces aces of the teeth are affected, and the surfaces subject to attrition show wear. Brown stain is frequently a disfiguring feature.

Severe - All enamel surfaces are affected and hypoplasia is so marked that the general form of the tooth may be affected. The major diagnostic sign of this classification is discrete or confluent pitting. Brown stains are widespread and teeth often present a corroded-like appearance.

In 1985, incidence of dental fluorosis ranged from 28 to 76 percent of U.S children aged 8 to 15. Fluorosis factors include community water-fluoride concentrations and/or the amount of fluoride consumed from all sources. Moderate and severe forms of dental fluorosis were found to represent between five and six percent of the cases of fluorosis nationally.

The estimated daily fluoride intake of a 44 lb. child drinking water in the 0.7 to 1.2 "optimal" range is 0.9 to 3.6 mg. Estimated intake for a 110 lb. adult drinking "optimally" fluoridated water is .58 to 6.6 mg/day.

1) Dental Science In A New Age, A History of the National Institute of Dental Research. Ruth Roy Harris. Montrose Press, Rockville, Maryland, 1989. pp 53, 56, 58.

Studies of mottled tooth enamel in the late 1930's led to a new medical term, "endemic hypoplasia", to describe mottled enamel. Whereas "endemic" is something identified with a particular area, "hypoplasia" meant "defective or incomplete formation" of tooth enamel.

Dr. H. Trendley Dean, the "Father of Fluoridation" referred to mottled enamel as "fluorosis" and considered fluoride at amounts above 1 ppm (1 mg fluoride/ liter water) the cause of the condition.

2) Health Effects of Ingested Fluoride. National Academy Press, Wash.,D.C.1993. p37,44,45.
Several detailed reviews of the literature comparing fluorosis data over time, in addition to other recent research, conclude that the prevalence of dental fluorosis reported in optimally fluoridated areas (both natural and added) in recent years ranged from 8% to 51 %, compared with 3% to 26% in nonfluoridated areas.

More recently, a prevalence of 80.9% was reported in children 12-14 years old in Augusta, Georgia, the highest prevalence yet reported in an optimally fluoridated community in the United States. Moderate-to-severe fluorosis was found in 14% of these children.

Russell (1962), in the Grand Rapids fluoridation study, noted that fluorosis was twice as prevalent among African-American children than white children. In the Texas surveys in the 1980's, the odds ratio for African-American children having dental fluorosis compared with Hispanic and non-Hispanic white children was 2.3 to 1. Dental fluorosis also tended to be more severe among African-American children than white children in the Georgia study.