Mottled enamel

The presence of fluorine as a soluble fluoride in drinking water to the extent of 2 ppm may cause mottled enamel in teeth, when used by children acquiring permanent teeth in smaller amounts, however, fluorides are added to water supplies to prevent dental cavities. 

H. T. Dean, Classification of mottled enamel diagnosis, J. Am. Dent. Assoc. 21 (1934) 1421-1426. 

The relationship between fluoride and dental caries was first noted in the early part of the 20th century when it was observed that residents of certain areas of USA developed brown stains on their teeth. In the 1930s, it was observed that the prevalence and severity of this type of mottled enamel was directly related to high amounts of ingested fluoride [34],... 

Naturally fluoridated foods and water have been ingested for decades with no serious side effects. In addition, public fluoridation has been widespread in this country for over 30 years without serious adverse effects. The incidence of mottled enamel, one of the earliest and most sensitive signs of fluoride toxicity, has not increased significantly in the past 15 years of water fluoridation. The safety and efficacy of fluoride has definitely been established, with no scientific evidence against fluoridation. 

Fluoride poisoning can occur after chronic ingestion of excessive amounts of fluoride, causing osteosclerosis and dental fluorosis (mottled enamel), due to accidental ingestion of fluoride mixtures during dental treatment (7,8), or after ingestion of insecticides or rodenticides containing fluoride salts. 

Dr. H. Trendley Dean, US PHS Reported on his on observation of thousands of children in community with varying fluoride levels. His research established mottled enamel index, which measured the severity of the discoloring of the teeth enamel from fluoride. 

How Mottled Enamel Relates to Fluoride in the Water Supply... 

At the same time, McKay was informed of an outbreak of mottled enamel in children who lived in Bauxite, a town near Colorado Springs. Bauxite was named for large deposits of bauxite, which the Aluminum Company of America (ALCOA) mined there. Children who drank spring- or shallow-well water had normal teeth, but children drinking deep-well water had severe enamel mottling. In 1931, ALCOA s chief chemist,... 

Mottled Enamel Is Moderate to Severe Enamel Fluorosis... 

Fig. 16.2 Mottled enamel, (a) Severe mottling. Note the wear at the coronal edge of the central incisors, the brown color, and holes on the coronal half of the crowns and the opaque white color interspersed with brown spots on the apical half (Figure downloaded from The Free Dictionary http //img. tfd.com/mosby/thumbs/500087-fxl2.jpg). (b) Mild mottling. Note the speckles of opaque white color on the labial surface of the central incisors. Other teeth may be similarly affected (Figure is a gift from Dr. Kenneth W. Stephens, University of Glasgow College of Dentistry)...

Dr. Churchill, read McKay s reports and ordered a test that identified trace elements in water using a new quartz spectroscope. The instrument identified fluoride in the deep wells only. McKay then obtained samples of drinking water from the many communities where he knew mottled enamel was found and Churchill confirmed the presence of fluoride. The association of fluoride with mottled enamel was published in the Scientific American in 1931. 

Fluoride is both incorporated into enamel crystals and also affects the enzymes involved in enamel formation (Sect. 16.2.2), causing mottled enamel, a severe example of enamel fluorosis. Enamel fluorosis is evident as specks or white flecks on the enamel surface (Fig. 16.2b). In 1941, the public water supply of Aurora (IL) contained 1.2 ppm of fluoride (F), but only 5% of teeth exhibited fluorosis, mostly premolars and second molars. A sensitive index of... 

Fig. 16 3 Geographic location of mottled enamel in the US (1941) (Figure is a reproduction of Fig. 2 from Dean HT, Kitchin P, Moulton FR (eds) Fluorine and dental health. American Association of the Advancement of Science Publication No 19 Washington DC 1942 AAAS 1942, pp. 6-11)...

The fluoride ion can replace the hydroxide ion in a crystal without significantly altering its structure, an isomorphous ion replacement. Fluoride also affects the enzymes involved in enamel formation, causing mottled enamel, a severe example of enamel fluorosis. White opaque patches on the normally translucent enamel indicate mild fluorosis. Fluorosis is measured on a grade of 0-5 where 1 through 3 indicate an increased cover of opaque white patches on the tooth surface, and 4 and 5 indicate an increased mottling. The two worst affected teeth make up an individual s score. The community s index of fluoridation is the mean score for all individuals. As the natural or artificial fluoride concentration of the water supply increases to 1 ppm, the mean number of cavities in 10-12 year-old children decreases from 7 to 3. Above 1 ppm fluoride, caries does not decrease much more, but the index of fluorosis increases markedly. This is the reason why public water supplies are fluoridated to only 1 ppm and not more or less. 

Caution Dangerous to inhale. Strong caustic action On eyes, skin, mucous membranes. Chronic absorption can canse mottled enamel of teeth, osteosclerosis and calcification of ligaments. 

CHRONIC HEALTH RISKS mottled enamel of teeth osteosclerosis calcification of ligaments. 

Chronic fluoride intoxication is more common and, since fluoride is concentrated in the hard tissues, the bones and teeth show the most obvious effects of fluorosis. Intake of excessive amounts of fluoride during tooth development results in mottled enamel which is characterized by the presence of scattered irregular white flecks. The permanent teeth are particularly susceptible. Towards the end of the last century this condition was found to be of common... 

It was shown by Dean that, where the level of fluoride in the water was about 1 mg per litre (1 ppm), the incidence of mottled enamel was slight while the incidence of caries was 50% lower than in places where the water contained 0-2 mg of fluoride per litre or less. Where the level of fluoride was 2 mg per litre there was a slight further decrease in the incidence of caries but an increase in the degree of mottling. As a result of this and many other studies, it was concluded that the optimal level of fluoride in the water supply in temperate climates is about 1 mg per litre. From 1945 onwards, studies on the effects of raising the fluoride level of the communal water supply to approximately 1 mg per litre were made in various parts of the world. 

Fluoride F- Cause of mottled enamel in teeth. Also used for control of dental decay. Not usually significant industrially. Adsorption with magnesium hydroxide, calcium phosphate, or bone black. Alum coagulation. 

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