Fluoride Sentence Examples

fluoride
  • With the exception of the fluoride, these substances are readily soluble in water and arc deliquescent.

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  • In some respects there is a very marked difference between fluorine and the other members of the group, for, whilst sodium chloride, bromide and iodide are readily soluble in water, sodium fluoride is much less soluble; again, silver chloride, bromide and iodide are practically insoluble in water, whilst, on the other hand, silver fluoride is appreciably soluble in water.

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  • Stannous Fluoride, SnF 2, is obtained as small, white monoclinic tables by evaporating a solution of stannous oxide in hydrofluoric acid in a vacuum.

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  • The hydrated fluoride, CrF3.9H20, obtained by adding ammonium fluoride to cold chromic sulphate solution, is sparingly soluble in water, and is decomposed by heat.

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  • The fluoride is found native as sellaIte, and the bromide and iodide occur in sea water and in many mineral springs.

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  • Scheele had done, and because he was employing a glass vessel he got "fluor acid air" (silicon fluoride).

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  • Moissan in 1886 by the electrolysis of pure anhydrous hydrofluoric acid containing dissolved potassium fluoride.

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  • It can also be prepared in the anhydrous condition by passing a current of hydrogen over dry silver fluoride.

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  • It may be condensed to a dark red liquid which is decomposed by moist air into chromic acid and chromic fluoride.

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  • Crystallized alumina is also obtained by heating the fluoride with boron trioxide; by fusing aluminium phosphate with sodium sulphate; by heating alumina to a dull redness in hydrochloric acid gas under pressure; and by heating alumina with lead oxide to a bright red heat.

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  • Aluminium fluoride, AlF 3, obtained by dissolving the metal in hydrofluoric acid, and subliming the residue in a current of hydrogen, forms transparent, very obtuse rhombohedra, which are insoluble in water.

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  • In 1886 he succeeded in obtaining the element fluorine in the free state by the electrolysis of potassium fluoride and anhydrous hydrofluoric acid at a low temperature.

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  • Thallous fluoride, T1F, forms white glistening octahedra; it is obtained by crystallizing a solution of the carbonate in hydrofluoric acid.

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  • It resembles potassium fluoride in forming an acid salt, T1HF 2.

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  • The bromide MnBr2.4H20, iodide, Mn12, and fluoride, MnF2, are known.

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  • Manganic Fluoride, MnF3, a solid obtained by the action of fluorine on manganous chloride, is decomposed by heat into manganous fluoride and fluorine.

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  • The salts of scandium are all colourless, the chloride and bromide corresponding in composition to Sc 2 X 6.12H 2 0; the fluoride is anhydrous.

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  • Thorium fluoride, ThF 4, is obtained as a heavy white insoluble powder by dissolving the hydrate in hydrofluoric acid and evaporating.

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  • By precipitating a thorium salt with a fluoride, a gelatinous hydrate, ThF 4.4H 2 O, is obtained.

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  • Acid potassium fluoride precipitates K2ThF6 4ThF4 H20 from a solution of thorium chloride.

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  • Potassium thorofluoride, K2ThF6 4H20, is a heavy black powder formed by boiling the hydroxide with potassium fluoride and hydrofluoric acid.

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  • Cupric fluoride, CuF 2, is obtained by dissolving cupric oxide in hydrofluoric acid.

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  • Antimony trifluoride, SbF 3, is obtained by dissolving the trioxide in aqueous hydrofluoric acid or by distilling antimony with mercuric fluoride.

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  • Silver fluoride, AgF, is obtained as quadratic octahedra, with one molecule of water, by dissolving the oxide or carbonate in hydrofluoric acid.

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  • Even the strongest laboratory oxidizing agents are unable to oxidize hydrogen fluoride.

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  • We have shown that fluoride anions can be used to generate helical structures in the solid state.

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  • Thorough brushing by carers and the use of antibacterial gels and fluoride help to prevent dental caries and gum disease.

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  • Reported use of fluoride toothpaste has a consistent effect in reducing dental caries across Europe using national data.

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  • It reacts with moisture to form hydrogen fluoride, a highly corrosive acid.

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  • This fluoride would come from food and drink or from fluoride dietary supplements.

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  • The first is the comparatively very high lattice enthalpy of the solid fluoride.

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  • The volume of the samples was measured, they were analyzed for fluoride concentration and the 24-hour urinary fluoride excretion was calculated.

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  • Anybody with a varied diet will anyway ingest adequate fluoride.

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  • The whole purpose of adding fluoride to water is to derive a medical benefit.

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  • Benefits of green tea Green tea also contains fluoride which is good for the teeth.

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  • Do you think people are wrong to protest about putting fluoride in the water supply?

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  • Liquid hydrogen fluoride is also a very strong acid for the same reason.

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  • The crystal used in this experiment is lithium fluoride.

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  • The fluoride added to water is 20 times more toxic than calcium fluoride, which occurs naturally in many waters.

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  • Meade Optical Coatings Aluminum Coatings with magnesium fluoride over coat provides bright images full of detail.

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  • We offer the use of topical fluoride following the restoration of teeth by our modern materials.

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  • Offices have access to drinking water (not yet with added fluoride) it is provided on tap.

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  • The fluoride in toothpastes is a chemical made from the mineral fluorite.

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  • So have Japan and India, where fluoride occurs naturally and skeletal fluorosis (thickening of bones) is prevalent.

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  • Fluoride is implicated in pre-senile dementia and Alzheimer's disease. n. Fluoride causes fluorosis.

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  • In those cases, all you get produced are the steamy fumes of the hydrogen halide - hydrogen fluoride or hydrogen chloride.

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  • That's equally true for hydrogen fluoride or hydrogen iodide.

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  • Using a good fluoride mouthwash will help gum infections and, if you gargle, it can stop you getting sore throats.

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  • We basically just do not show any deficiencies of phosphorous, potassium, sodium, sulfur, chloride or fluoride.

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  • The chloride gives a white precipitate; the fluoride doesn't give a precipitate.

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  • A fluoride mouth rinse can help prevent tooth decay.

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  • Everything you always DIDN'T want to know about fluoride For decades the message that fluoride safely prevents tooth decay has been considered sacrosanct.

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  • Hydrogen fluoride is very soluble due to hydrogen bonding with water molecules.

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  • In addition to sterility, fluoride would also, after a period of time, make an individual more submissive.

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  • The least one can do is brush teeth with fluoride free toothpaste!

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  • In areas where the water supply is fluoridated, fluoride toothpaste provides additional protection.

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  • An impure titanium was made by Wiihler and Sainte-Claire Deville in 1857 by heating to redness fluotitanate of potassium (see below) in the vapour of sodium in an atmosphere of dry hydrogen, and extracting the alkaline fluoride formed by water.

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  • Selenium fluoride, SeF4, is obtained as a colourless liquid by the direct action of fluorine or selenium (P. Lebeau, Comptes rendus, 1907, 144, p. 1042).

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  • The least one can do is brush teeth with fluoride free toothpaste !

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  • Use of toothpaste with fluoride is one of the major factors why children today have less tooth decay.

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  • The active substance of the new coating is a vinylidene fluoride copolymer.

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  • Fluoride and potassium nitrate are added to reduce tooth sensitivity.

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  • Fluoride over consumption while the teeth are forming will cause white patches in mild cases and brown areas or even pitting in severe cases.

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  • Just be certain you don't use fluoride or whitening types of toothpaste.

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  • Fluoride, found in toothpaste, drinking water, or dental treatments, also helps to protect teeth by binding with enamel to make it stronger.

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  • Preventative services that the dentist can perform include fluoride treatments, sealant application, and scaling (scraping off the hardened plaque, called tartar).

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  • These include making certain the child receives adequate fluoride and guarding against baby bottle decay.

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  • Fluoride is beneficial for babies even before their teeth erupt.

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  • In most municipal water supplies, the correct amount of fluoride is added for proper tooth development.

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  • If the water supply does not contain enough fluoride or if bottled water is used for drinking and cooking, the doctor or dentist should be informed.

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  • They may prescribe fluoride supplements for the baby.

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  • Parents should administer only a pea-size amount of fluoride toothpaste that is made especially for children.

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  • Fluoride is also very helpful in preventing tooth decay.

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  • If the town's water is not fluoridated, the parent should ask the dentist for fluoride supplements.

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  • Extra brushing with specially shaped and/or electric toothbrush and fluoride toothpaste is required around the areas where the braces or appliances attach to the teeth.

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  • A fluoride mouthwash may be recommended.

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  • In many areas, drinking water contains fluoride that meets all normal needs, but for children who do not drink water or drink filtered or bottled water, fluoride supplements may be useful.

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  • Fluoride supplements may be useful for infants and then may be discontinued as the child gets older and starts drinking water.

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  • This rate decrease is explained in part by the fact that more areas have added fluoride to their drinking water and more children get regular, good dental care.

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  • If the problem is caught early, the teeth involved can be treated with fluoride, followed by changes in the infant's feeding habits and better oral hygiene.

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  • The four major prevention strategies are proper oral hygiene, fluoride, sealants, and attention to diet.

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  • They should apply only a very small amount (the size of a pea) of toothpaste containing fluoride.

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  • Too much fluoride may cause spotting (fluorosis) of the tooth enamel.

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  • Fluoride is a natural substance that slows the destruction of enamel and helps to repair minor tooth decay damage by remineralizing tooth structure.

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  • Toothpaste, mouthwash, fluoridated public drinking water, and vitamin supplements are all possible sources of fluoride.

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  • Children living in areas without fluoridated water should receive 0.25 mg/day of fluoride before age three, 0.5 mg/day of fluoride from three to six years of age, and 1 mg/day after age six.

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  • Sometimes children can also have their teeth treated with fluoride at the dentist's office.

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  • Because fluoride is most beneficial on the smooth surfaces of teeth, sealants were developed to protect the irregular surfaces of teeth.

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  • Fluoridation is the addition of fluoride to water supplies to help prevent tooth decay.

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  • It occurs as fluoride ion in combination with other elements such as sodium.

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  • Most water supplies naturally contain low levels of fluoride.

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  • The levels of naturally occurring fluoride in fresh water range from less than 0.1 ppm to more than 13 ppm.

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  • Systemic fluorides, including fluoridated water and prescription fluoride supplements supplied as tablets, drops, or lozenges, can be incorporated into the enamel of children's developing teeth.

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  • When enough fluoride from water, supplements, food, or other sources enters the bloodstream and reaches the teeth while the enamel is forming, the fluoride can replace a piece of the hydroxyapatite molecule to form fluorapatite.

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  • Thus fluoride becomes part of the tooth enamel.

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  • Fluoride makes the tooth more resistant to acids produced by the bacteria that cause tooth decay.

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  • It is unlikely that sufficient fluoride will be incorporated into the enamel throughout the years of crown formation.

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  • With optimally fluoridated water (1 ppm) as the primary source of fluoride, a child would have to drink two quarts of water every day for 12 to 14 years to incorporate fluoride into all of the baby and adult teeth as they form.

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  • The child would be ingesting about 2 mg. of fluoride daily.

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  • Other topical fluorides include fluoridated toothpastes and mouthwashes and fluoride gels that are applied to children's teeth at dental examinations.

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  • Topical fluoride is the most effective mineral for renewing or remineralizing the surface layers of enamel and dentin as they wear out and are eaten away by acids from food and bacteria.

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  • Fluoride remineralization makes the tooth surface more resistant to decay and reverses early decay processes.

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  • Fluoridated water is a major source of fluoride.

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  • Most bottled water contains only trace amounts of fluoride.

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  • Children who drink water that is low in fluoride may be given fluoride supplements.

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  • Fluoride occurs in many different foods and is also added to some foods.

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  • Fruits and vegetables may contain more than 0.2 mg of fluoride per serving, depending on where they were grown and whether fluoridated water was used for irrigation and processing.

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  • The amount of fluoride in beverages depends on the amount of fluoride in the water used to make them.

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  • Many vitamins and medicines also contain fluoride.

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  • Fluoridated toothpastes and mouthwashes contain high amounts of fluoride.

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  • A tube of fluoridated toothpaste may contain as much as 1 to 2 gm of fluoride.

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  • Nonprescription mouthwashes can contain up to 120 mg of fluoride.

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  • The average child using the typical amount of fluoridated toothpaste will swallow or absorb 0.5 to 1.0 mg. of fluoride per brushing.

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  • The widespread use of fluoridated toothpastes and mouthwashes has increased children's sources of fluoride significantly.

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  • McKay eventually discovered that this "mottling"-as he called it-resulted from high levels of naturally occurring fluoride in the drinking water.

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  • The fluoride levels used are completely safe.

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  • Any fluoride above the naturally occurring (usually trace) amounts is unnecessary and possibly toxic.

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  • An individual dose of fluoride cannot be controlled because it depends on the amount of fluoridated water that a child ingests each day.

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  • Although fluoride may help prevent decay, good diet, good oral hygiene, and regular dental cleanings can be just as effective.

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  • Fluoride can be toxic and even fatal at higher doses.

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  • The difference between the amount of fluoride that is beneficial and the amount that can cause mottling is only two to four-fold.

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  • People vary in their susceptibility to the effects of fluoride.

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  • It is impossible to determine how much fluoride a child is ingesting because of the numerous sources of fluoride in food and products; a child may regularly drink water from sources with different fluoride levels.

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  • Fluoride is ineffective against gum disease, the major destroyer of teeth.

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  • There is some disagreement as to whether fluoride is an essential mineral in humans.

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  • Relatively low levels of fluoride (20-80 mg) are considered toxic.

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  • Less than 1 gm of fluoride can be fatal to a small child.

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  • Fluoride supplements often are prescribed for children who drink nonfluorinated water and do not use fluoride toothpaste.

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  • Fluoride supplements should not be used if the drinking water contains more than 0.6 ppm of fluoride.

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  • One ppm of fluoride is equivalent to about 1 mg per quart (or liter) of water.

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  • Fluoride supplements should not be given to babies under six months of age regardless of the fluoride content of the water.

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  • Babies get adequate fluoride from breast milk or infant formula.

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  • A child easily can swallow enough fluoridated toothpaste to exceed the recommended daily amount of fluoride by four-fold.

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  • A medium-sized toothpaste tube contains enough fluoride to make a child seriously ill or even cause death should the child eat it all.

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  • As little as four to eight mg of fluoride ingested daily while the tooth enamel is forming can cause mottling-often called fluorosis-in children under age eight.

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  • Weekly rinsing with a fluoride mouthwash can reduce decay in children by 20-40 percent.

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  • Fluoride supplements can reduce decay in children by 40 percent, if administered at least 150 days of every year that enamel is forming.

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  • Topical fluoride treatments given in a dentist's office have been proven to be 40 percent or more effective in preventing decay.

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  • These treatments include fluoride gels and foams and fluoride varnishes.

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  • They are more concentrated than other fluoride treatments and so are less likely to be ingested.

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  • They continue to provide fluoride to the enamel for about 24 hours after application.

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  • Varnishes may be particularly appropriate for young children and those with special needs since varnishes do not require the use of a fluoride tray.

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  • It is the parents' responsibility to monitor their child's fluoride intake.

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  • Pregnant and nursing mothers should pay close attention to how much fluoride they ingest.

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  • Mottling-Fluorosis; spotting on the teeth due to excess fluoride as the tooth enamel is forming.

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  • They do root planning, take x-rays, and apply sealants and fluoride treatments to protect against cavities.

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  • Additional nutrients necessary for optimum nutrition include chloride, potassium, sodium, chromium, copper, iodine, fluoride, manganese, molybdenum, selenium, and zinc.

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  • The water being purified means that the body does not become further contaminated with any minerals or other ingredients such as fluoride which can appear in drinking water.

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  • Guardian covers special dental needs as well, including implants, cancer detection, periodontal services, fluoride treatments and other services that serve to ultimately reduce long-term dental health costs.

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  • The covered services include dental examinations, teeth cleanings and topical fluoride treatments provided for children under the age of 19 years.

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  • Cobalt fluoride, CoF 2.2H 2 0, is formed when cobalt carbonate is evaporated with an excess of aqueous hydrofluoric acid, separating in rose-red crystalline crusts.

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  • Electrolysis of a solution in hydrofluoric acid gives cobaltic fluoride, CoF3.

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  • Boron fluoride also combines with ammonia gas, equal volumes of the two gases giving a white crystalline solid of composition BF 3 NH 3 i with excess of ammonia gas, colourless liquids BF 3.2NH 3 and BF 3.3NH 3 are produced, which on heating lose ammonia and are converted into the solid form.

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  • A masterly device, initiated by him, was to collect gases over mercury instead of water; this enabled him to obtain gases previously only known in solution, such as ammonia, hydrochloric acid, silicon fluoride and sulphur dioxide.

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  • In the same year as Klaproth detected uranium, he also isolated zirconia or zirconium oxide from the mineral variously known as zircon, hyacinth, jacynth and jargoon; but he failed to obtain the metal, this being first accomplished some years later by Berzelius, who decomposed the double potassium zirconium fluoride with potassium.

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  • In 1824 he obtained zirconium from potassium zirconium fluoride; the preparation of (impure) titanium quickly followed, and in 1828 he obtained thorium.

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  • Balard completed for many years Berzelius's group of " halogen " elements; the remaining member, fluorine, notwithstanding many attempts, remained unisolated until 1886, when Henri Moissan obtained it by the electrolysis of potassium fluoride dissolved in hydrofluoric acid.

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  • This salt gives the corresponding chloride and fluoride with hydrochloric and hydrofluoric acids, and the phosphate, Pb(HP04)2, with phosphoric acid.

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  • Lead fluoride, PbF2, is a white powder obtained by precipitating a lead salt with a soluble fluoride; it is sparingly soluble in water but readily dissolves in hydrochloric and nitric acids.

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  • A chlorofluoride, PbC1F, is obtained by adding sodium fluoride to a solution of lead chloride.

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  • Columbium hydride, CbH, is obtained as a greyish metallic powder, when the double fluoride, CbF 5, 2 KF, is reduced with sodium.

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  • With hydroflouric acid it yields uranous fluoride, UF 4, which forms double salts of the type MF UF 4.

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  • Stannic Fluoride, SnF 4, is obtained in solution by dissolving hydrated stannic oxide in hydrofluoric acid; it forms a characteristic series of salts, the stannofluorides, M 2 SnF 6, isomorphous with the silico-, titano-, germanoand zirconofluorides.

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  • The refractive indices of all glasses at present available lie between 1.46 and 1 90, whereas transparent minerals are known having refractive indices lying considerably outside these limits; at least one of these, fluorite (calcium fluoride), is actually used by opticians in the construction of certain lenses, so that probably progress is to be looked for in a considerable widening of the limits of available optical materials; possibly such progress may lie in the direction of the artificial production of large mineral crystals.

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  • Silicon fluoride, SiF4, is formed when silicon is brought into contact with fluorine (Moissan); or by decomposing a mixture of acid potassium fluoride and silica, or of calcium fluoride and silica with concentrated sulphuric acid.

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  • It burns with a pale-blue flame forming silicon fluoride, silicofluoric acid and silicic acid.

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  • Silicofluoric acid, H2SiF6, is obtained as shown above, and also by the action of sulphuric acid on barium silicofluoride, or by absorbing silicon fluoride in aqueous hydrofluoric acid.

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  • The anhydrous acid is not known, since on evaporating the aqueous solution it gradually decomposes into silicon fluoride and hydrofluoric acid.

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  • They have been obtained artificially by Hautefeuille by the interaction of titanium fluoride and steam.

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  • Strontium fluoride, SrF 2, is obtained by the action of hydrofluoric acid on the carbonate, or by the addition of potassium fluoride to strontium chloride solution.

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  • It may be obtained crystalline by fusing the anhydrous chloride with a large excess of potassium hydrogen fluoride or by heating the amorphous variety to redness with an excess of an alkaline chloride.

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  • Troost produced crystallized zirconium by fusing the double fluoride with aluminium in a graphite crucible at the temperature of melting iron, and extracting the aluminium from the melt with hydrochloric acid.

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  • For its extraction from zircon the mineral is heated and quenched in water to render it brittle, and then reduced to a fine powder, which is fused with three to four parts of acid potassium fluoride in a platinum crucible.

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  • The double fluoride is decomposed with hot concentrated sulphuric acid; the mixed sulphate is dissolved in water; and the zirconia is precipitated with ammonia in the cold.

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  • Zirconium fluoride, ZrF4, is obtained as glittering monoclinic tables (with 3H 2 0) by heating zirconia with acid ammonium fluoride.

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  • Thus the sulphate constitutes the minerals anhydrite, alabaster, gypsum, and selenite; the carbonate occurs dissolved in most natural waters and as the minerals chalk, marble, calcite, aragonite; also in the double carbonates such as dolomite, bromlite, barytocalcite; the fluoride as fluorspar; the fluophosphate constitutes the mineral apatite; while all the more important mineral silicates contain a proportion of this element.

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  • Whereas calcium chloride, bromide, and iodide are deliquescent solids, the fluoride is practically insoluble in water; this is a parallelism to the soluble silver fluoride, and the insoluble chloride, bromide and iodide.

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  • Calcium fluoride, CaF2, constitutes the mineral fluor-spar, and is prepared artificially as an insoluble white powder by precipitating a solution of calcium chloride with a soluble fluoride.

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  • The fluorine, which is liberated as a gas at the anode, is passed through a well cooled platinum vessel, in order to free it from any acid fumes that may be carried over, and finally through two platinum tubes containing sodium fluoride to remove the last traces of hydrofluoric acid; it is then collected in a platinum tube closed with fluor-spar plates.

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  • Its most important property is that it rapidly attacks glass, reacting with the silica of the glass to form gaseous silicon fluoride, and consequently it is used for etching.

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  • Fluorides can be readily detected by their power of etching glass when warmed with sulphuric acid; or by warming them in a glass tube with concentrated sulphuric acid and holding a moistened glass rod in the mouth of the tube, the water apparently gelatinizes owing to the decomposition of the silicon fluoride formed.

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  • Cryolite, a fluoride of aluminium and sodium, is extensively mined in Greenland and elsewhere for industrial purposes.

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  • The fluoride, NaF, is sparingly soluble in water (I part in 25).

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  • It forms the acid fluoride KHF 2 when dissolved in aqueous hydrofluoric acid, a salt which at a red heat gives the normal fluoride and hydrofluoric acid.

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  • The fluoride, CrF3, results on passing hydrofluoric acid over the heated chloride, and sublimes in needles.

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  • Cryolite (A1F 3.5NaF) is a double fluoride of aluminium and sodium, which is scarcely known except on the west coast of Greenland.

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  • Cryolite is not a safe body to electrolyse, because the minimum voltage needed to break up the aluminium fluoride is 4.0, whereas the sodium fluoride requires only 4.7 volts; if, therefore, the current rises in tension, the alkali is reduced, and the final product consists of an alloy with sodium.

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  • Grabau patented a method of reducing the simple fluoride of aluminium with sodium, and his process was operated at Trotha in Germany.

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  • Minet took out patents for electrolysing a mixture of sodium chloride with aluminium fluoride, or with natural or artificial cryolite.

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  • As a part of the voltage is consumed in the latter duty, only the residue can be converted into chemical work, and as the theoretical voltage of the aluminium fluoride in the cryolite is 4.0, provided the bath is kept properly supplied with alumina, the fluorides are not attacked.

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  • Heated in a glass tube it gives silicon fluoride, phosphorus and sulphur, PSF 3 = PF3-f-S; 4PF 3 +3S10 2 = 3SiF 4 +P 4 +30 2.

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  • With dry ammonia it gives ammonium fluoride and a compound P(NH2)2SF.

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  • Ferrous fluoride, FeF21 is obtained as colourless prisms (with 8H2O) by dissolving iron in hydrofluoric acid, or as anhydrous colourless rhombic prisms by heating iron or ferric chloride in dry hydrofluoric acid gas.

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  • Ferric fluoride, FeF 31 is obtained as colourless crystals (with 42H2O) by evaporating a solution of the hydroxide in hydrofluoric acid.

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  • It forms numerous compounds with potassium fluoride.

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  • It is important that younger children only use a very small amount of fluoridated toothpaste since using too much fluoride can be toxic to infants.

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