Fluoridation and dental caries

E. Newbmn, ed.. Fluorides and Dental Caries Charles C Thomas PubHshers, Springfield, HI., 1975. 

S.R. Estupinan-Day, R. Baez, H. Horowitz, R. Warpela, B. Sutherland, M. Thamer, Salt fluoridation and dental caries in Jamaica, Commun. Dent. Oral Epidemiol. 29 (2001) 247-252. 

F.J. McClure, Ingestion of fluoride and dental caries, quantitative relations based on food and water requirements of children one to twelve years old. Am. J. Dis. Child. 66 (1943) 362-369. 

D.J. Forrester, E.M. Schultz, Proceedings of the International Workshop on Fluorides and Dental Caries Reduction, University of Maryland, Baltimore, MD, 1974. 

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],... 

J. Arends, J. Christoffersen, Nature and role of loosely bound fluoride in dental caries, J. Dent. Res. 69 (1990) 601-605. 

A. Thylstrup, O. Fejerskov, C. Bruun, J. Kann, Enamel changes and dental caries in 7-year-old children given fluoride tablets from shortly after birth. Caries Res. 13 (1979) 265-276. 

S.A. Ekiund, B.A. Burt, A.I. Ismail, J.J. Calderone, High fluoride drinking water, fluorosis, and dental caries in adults, J. Am. Dent. Assoc. 114 (1987) 324-328. 

There is no direct evidence that the consumption of simple sugars is harmful. Contrary to folklore, diets high in sucrose do not lead to diabetes or hypoglycemia. Also contrary to popular belief, carbohydrates are not inherently fattening. They yield 4 kcal/g (the same as protein and less than half that of fat, see Figure 27.5), and result in fat synthesis only when consumed in excess of the body s energy needs. However, there is an association between sucrose consumption and dental caries, particularly in the absence of fluoride treatment. 

The dental examination of thousands of children and adults and the analysis of hundreds of water supply sources for fluoride have shown a remarkable relationship between the concentration of waterborne fluoride and the incidence of dental caries. As a result, the following general relationships between fluoride level and dental caries can be stated (1,5,9,12) ... 

Fluoridation of potable water suppHes for the prevention of dental caries is one of the principal uses for sodium fluoride (see Water, municipal WATER treatment). Use rate for this appHcation is on the order of 0.7 to 1.0 mg/L of water as fluoride or 1.5 to 2.2 mg/L as NaF (2). NaF is also appHed topically to teeth as a 2% solution (see Dentifrices). Other uses are as a flux for deoxidiziag (degassiag) rimmed steel (qv), and ia the resmelting of aluminum. NaF is also used ia the manufacture of vitreous enamels, ia pickling stainless steel, ia wood preservation compounds, caseia glues, ia the manufacture of coated papers, ia heat-treating salts, and as a component of laundry sours. 

Fluoride is added to table salt in countries such as France, Mexico, and Switzerland for the prevention of dental caries. 

Fluoride. A fluoride concentration of ca 1 mg/L is helpful in preventing dental caries. Eluoride is deterrnined potentiometrically with an ion-selective electrode. A buffer solution of high total ionic strength is added to the solution to eliminate variations in sample ionic strength and to maintain the sample at pH 5—8, the optimum range for measurement. (Cyclohexylenedinitrilo)tetraacetic acid (CDTA) is usually added to the buffer solution to complex aluminum and thereby prevent its interference. If fluoroborate ion is present, the sample should be distilled from a concentrated sulfuric acid solution to hydrolyze the fluoroborate to free fluoride prior to the electrode measurement (26,27). 

Mechanical removal of plaque is the most effective measure against plaque-caused diseases, dental caries, and periodontal diseases. Even before the advent of fluoride treatments, it was assumed that a clean tooth does not decay. A toothbmsh is effective in removing dental plaque and, for those individuals who optimize its use, it usually can adequately control plaque. Despite the proven efficacy of mechanical plaque removal, the amount of patient involvement is such that only about 30% of the population in developed countries and considerably less in undeveloped countries can be expected to adequately remove plaque (1). Hence, supplementary measures such as dentifrices and dental rinses are necessary. 

Eluoride added to a compatible dentifrice base at a level of 1000 ppm has been clinically proven to reduce the incidence of dental caries by about 25% on average, even in areas where the water supply is fluoridated (4). Elevation to 1500 ppm increases the protection. Sources of fluoride approved for use in dentifrices are sodium fluoride [7681-49-4] (0.22%), sodium monofluorophosphate (0.76%), and stannous fluoride [7783-47-3] (0.41%). The Eood and Dmg Administration regulates fluoridated dentifrices as dmgs and has estabUshed parameters for safe and effective products. CompatibiUty of the fluoride with the abrasive is an important requirement. 

The incidence of dental caries has decreased dramatically in recent years. It has fallen to such an extent as to reduce the need for professional dental health services related to caries significantly. The cause is not clear, but water fluoridation, addition of fluoride to toothpaste, and other modes of fluoride adrninistration are generally conceded to be important contributors to the phenomenon and the American Dental Association recommends use of a fluoride toothpaste for all patients (10). 

F H. T. Dean et al. put the correlation between decreased incidence of dental caries and the presence of fluoride ions in drinking water on a quantitative basis... 

NaF for water fluoridation, wood preservatives, the formulation of insecticides and fungicides, and use as a fluxing agent. It is also used to remove HF from gaseous Fz in the manufacture and purification of Fz-SnFz in toothpastes to prevent dental caries,... 

Dissolved mineral salts The principal ions found in water are calcium, magnesium, sodium, bicarbonate, sulphate, chloride and nitrate. A few parts per million of iron or manganese may sometimes be present and there may be traces of potassium salts, whose behaviour is very similar to that of sodium salts. From the corrosion point of view the small quantities of other acid radicals present, e.g. nitrite, phosphate, iodide, bromide and fluoride, have little significance. Larger concentrations of some of these ions, notably nitrite and phosphate, may act as corrosion inhibitors, but the small quantities present in natural waters will have little effect. Some of the minor constituents have other beneficial or harmful effects, e.g. there is an optimum concentration of fluoride for control of dental caries and very low iodide or high nitrate concentrations are objectionable on medical grounds. 

Stannous fluoride is used in toothpastes and dental rinses to protect tooth enamel from attack by bacteria—cavities (also known as dental caries). It was the first fluoride used for that purpose, in the toothpaste Crest. 

Horowitz, H. S. (1973). A review of systematic and topical fluorides for the prevention of dental caries. Community Dentistry Oral Epidemiology, 1, 104-14. 

Controlled and sustained drug delivery has recently begun to make an impression in the area of treatment of dental diseases. Many researchers have demonstrated that controlled delivery of antimicrobial agents, such as chlorhexidine [128-130], ofloxacin [131-133], and metronidazole [134], can effectively treat and prevent periodontitis. The incidence of dental caries and formation of plaque can also be reduced by controlled delivery of fluoride [135,136]. Delivery systems used are film-forming solutions [129,130], polymeric inserts [132], implants, and patches. Since dental disease is usually chronic, sustained release of therapeutic agents in the oral cavity would obviously be desirable. 

Most foods and drinking waters contain enough fluoride to result in the incorporation of significant amounts of fluoride into this mineral whereby the solubility decreases. Therefore, the system hydroxyapatite-fluorapatite is primarily of importance for the prevention of dental caries. However, in this context its theoretical treatment is important for geochemists who may be confronted with so-called subregular solid solutions. 

Fluoride is the salt, such as sodium fluoride, of the element fluorine. It is readily absorbed by the intestine and is incorporated into bone or tooth enamel. When incorporated into teeth, fluoride strengthens the outer layers of enamel, thus reducing dental caries. It is generally accepted that addition of fluoride to the drinking water (approximately 1 ppm) is beneficial for the reduction in childhood dental caries. 

Fluorine is an essential element involved in several enzymatic reactions in various organs, it is present as a trace element in bone mineral, dentine and tooth enamel and is considered as one of the most efficient elements for the prophylaxis and treatment of dental caries. In addition to their direct effect on cell biology, fluoride ions can also modify the physico-chemical properties of materials (solubility, structure and microstructure, surface properties), resulting in indirect biological effects. The biological and physico-chemical roles of fluoride ions are the main reasons for their incorporation in biomaterials, with a pre-eminence for the biological role and often both in conjunction. This chapter focuses on fluoridated bioceramics and related materials, including cements. The specific role of fluorinated polymers and molecules will not be reviewed here. 

A major benefit of water fluoridation to children is that it reduces disparities between socio-economic groups [133,134], Children in lower socio-economic groups tend to suffer more severely from dental caries, and though the reasons for this are not clear, the result has been confirmed in many parts of the world. Children in these groups therefore benefit enormously from fluoridation of the water supply and in areas where the water supply is fluoridated, the differences in dental caries experience between the social classes are much less than in non-fluoridated areas [135],... 

The effect of fluoridation on adult dental health is harder to quantify. There are several reasons for this. Adults vary in the extent to which they may have been exposed to fluoride while growing up, and they may experience tooth loss for reasons other than dental caries, for example, trauma or periodontal disease. However, despite these difficulties, what evidence there is points to fluoride being beneficial for adult healthcare [136,137], and for older adults in particular, conditions such as root caries has been demonstrated quite clearly to be less prevalent in regions where the drinking water is fluoridated [138,139], The overall conclusion from all of these studies is that the whole population benefits from fluoridation in terms of improvements to their overall dental health. 

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