Use Of Fluoride Supplements Research Articles

Should the drinking water of Truro, Nova Scotia, be fluoridated? Water fluoridation in the 1990s

An epidemiological assessment of differences in caries and fluorosis prevalences between children in Truro (< 0.1 ppm) and Kentville (fluoridated at 1.1 ppm in 1991), Nova Scotia, Canada, was completed in 1991. Out of a total of 429 children, in grades 5 and 6, in the two towns in 1991, 219 (51%) were examined. Parents answered a self-administered questionnaire investigating the sources of drinking water used by the children since birth, residence history, use of fluoride supplements, dentifrices, and other fluoride products during the first 6 yr of the life. The examination criteria differentiated between non-cavitated and cavitated carious lesions. Dental fluorosis was measured using the TSIF index. Examiner agreement was excellent. Of the children examined, 80 (36.5%) drank water (fluoridated or non-fluoridated) from municipal water systems during the first 6 yr of life. The children were assigned into five groups based upon residence history and exposure to fluoridated water during the first 6 yr of life. The percentage difference in mean DMFS scores between children in the fluoridated and non-fluoridated groups is 17% (delta DMFS1 = 0.7) when non-cavitated carious lesions are included and 39% (delta DMFS2 = 1.1) when they are excluded. The differences are not statistically significant. The significant risk factors associated with the DMFS1 and DMFS2 scores identified by a stepwise multiple regression analysis are: education level of the father, gender, and number of years of reported use of toothpaste during the first 6 yr of life. Dental fluorosis (mainly TSIF score of 1) was present in 41.5% and 69.2% of the children in the non-fluoridated and fluoridated groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluoride Supplementation

To determine the protocol and use of prescriptions of fluoride supplementation by primary care pediatricians and pediatric dentists in the Houston (Tex) area. Survey mailed to all primary care pediatricians and pediatric dentists listed in the Yellow Pages of the Greater Houston telephone directory. 153 pediatricians and 47 pediatric dentists. Ninety-six percent of the participants prescribed fluoride supplements. Fifty-one percent of the pediatricians and 61% of the dentists considered that the fluoride content of the water was important. Seventy percent of the pediatricians and 30% of the dentists discontinued the use of supplements by age 7 to 10 years. Pediatricians and pediatric dentists should consider the need for water analysis prior to supplementation and should continue the use of fluoride supplements until 16 years of age.

Evaluation of appropriate use of dietary fluoride supplements in the US

Recent epidemiologic and related evidence suggests the following trends: 1. the prevalence of caries continues to decline in children of the US and several other developed countries; 2. the prevalence of mild dental fluorosis is increasing; 3. the majority of the cariostatic effects of fluoride are topical; and 4. dietary fluoride supplements are a risk factor for dental fluorosis. These trends, and the scientific evidence on fluoride and fluorosis, suggest that it is time to re-evaluate the use of dietary fluoride supplements. This paper examines the evidence for each of the four trends and the use of fluoride supplements in caries prevention today.

Biological mechanisms of fluorosis and level and timing of systemic exposure to fluoride with respect to fluorosis.

Enamel fluorosis can occur following either an acute or chronic exposure to fluoride during tooth formation. Fluorosed enamel is characterized by a retention of amelogenins in the early-maturation stage, and by the formation of a more porous enamel with a subsurface hypomineralization. The mechanisms by which fluoride affects enamel development include specific effects on both the ameloblasts and on the developing enamel matrix. Maturation-stage ameloblast modulation is more rapid in fluorosed enamel as compared with control enamel, and proteolytic activity in fluorosed early-maturation enamel is reduced as compared with controls. Secretory enamel appears to be more susceptible to the effects of fluoride following acute fluoride exposure, such as may occur with the use of fluoride supplements. However, both human and animal studies show that the transition/early-maturation stage of enamel formation is most susceptible to the effects of chronic fluoride ingestion at above-optimal levels of fluoride in drinking water.

Domestic water treatment appliances and the fluoride ion

Specific ion metering of fluoride ion levels of water samples obtained after passage through water softeners and a conditioner showed no alteration in concentration when compared with controls. Similar comparison of water samples passed through water filters demonstrated that highly significant amounts of fluoride ion were removed. In one filter tested, 90% of the fluoride content was lost in the filtration process. The findings of this study suggest that, in a household using a filter, it may be necessary to increase the fluoride supplement or in some cases to initiate use of fluoride supplements as children are not receiving as much fluoride as was thought. New guidelines are required to take account of this surprising effect.

Dental Caries and Fluoride Exposure in Western Australia

Most water supplies in Western Australia (WA) have been fluoridated since about 1968, but one region has persistently resisted. Supplement use has been encouraged there, and fluoride toothpaste is widely used. Caries prevalence and caries experience in children in Perth (F- 0.8 mg/L) have declined steadily since fluoridation, but in the Bunbury region (F- less than 0.2 mg/L), caries measures remain higher than in Perth. The purpose of this study was to correlate the magnitude and timing of fluoride exposure with caries experience. Altogether, 592 randomly selected children born in 1978 (mean age, 11.8 years) in Perth and the Bunbury region provided residence and fluoride exposure information for the periods from birth to four and from four to 12 years of age. Caries experience was recorded clinically in accordance with DMFT and WHO criteria. Sixty-one percent had been continuous residents of fluoridated areas from birth to four years, and 51% between the ages of four and 12 years. Fluoride supplement use was low. By the age of 1.5 years, 42% had used toothpaste. The prevalence of caries was 0.38 in Perth and 0.61 in the Bunbury region, and mean DMFT scores were 0.89 (SD, 1.39) and 1.57 (SD, 1.60), respectively. Bivariate analysis revealed all fluoride exposure to be associated with reduced caries experience, but there were large correlations between some variables. When unconditional logistic regression analysis was used, the most important (p less than 0.05) odds ratios associated with no caries experience were for residence in a fluoridated area from four to 12 years of age and early use of toothpaste.(ABSTRACT TRUNCATED AT 250 WORDS)

Enamel opacities in children whose mothers took part in a dental health education scheme

One well recognised cause of enamel opacities is excessive fluoride ingestion during the period of tooth development. In the past, "fluorosis", or opacities arising from this cause, has been reported to occur in children given fluoride supplements. In a large experiment in dental health education, fluoride supplements were given regularly to many of the children in two out of three experimental groups. 126 children were dentally examined 10 yr after the scheme began, of whom 79 had regularly received fluoride drops and/or tablets for at least part of the period between birth and 5 yr of age. Labial surfaces of each child's erupted incisor teeth were examined for enamel opacities. 75% of the 126 children had at least one affected tooth. There was a statistically insignificant, but consistent, trend for the prevalence of opacities to increase with increasing duration of use of fluoride supplements.

The Nature and Mechanisms of Dental Fluorosis in Man

Any use of fluorides, whether systemic or topical, in caries prevention and treatment in children results in ingestion and absorption of fluoride into the blood circulation. The mineralization of teeth under formation may be affected so that dental fluorosis may occur. Dental fluorosis reflects an increasing porosity of the surface and subsurface enamel, causing the enamel to appear opaque. The clinical features represent a continuum of changes ranging from fine white opaque lines running across the tooth on all parts of the enamel to entirely chalky white teeth. In the latter cases, the enamel may be so porous (or hypomineralized) that the outer enamel breaks apart posteruptively and the exposed porous subsurface enamel becomes discolored. These changes can be classified clinically by the TF index to reflect, in an ordinal scale, the histopathological changes associated with dental fluorosis. Compared with Dean's and the TSIF index, we consider the TF index to be more precise. Recent studies on human enamel representing the entire spectrum of dental fluorosis have demonstrated a clear association between increasing TF score and increasing fluoride content of the enamel. So far, no useful data on dose (expressed in mg fluoride/kg b.w.)-response (dental fluorosis) relationships are available. In this paper, we have, therefore, re-evaluated the original data by Dean et al. (1941, 1942), Richards et al. (1967), and Butler et al. (1985) from the USA, by applying the equation of Galagan and Vermillion (1957) which permits the calculation of water intake as a function of temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship of Total Fluoride Intake to Beneficial Effects and Enamel Fluorosis

Recent studies indicate that the prevalence of very mild to moderate dental fluorosis, as classified by Dean, has increased relative to that found in earlier investigations. To date, fluoridated water, fluoride supplements, the diet, fluoride dentifrices, and other topical fluoride applications have been identified as sources of systemic fluoride. Recent evidence suggests that there is a strong association between mild to moderate enamel fluorosis and the use of fluoride supplements during early childhood, and that the presently recommended supplementation schedule for U.S. children above the age of 2 years may be too high. Evidence also suggests that there is a strong association between fluoride dentifrice use during early childhood and enamel fluorosis in fluoridated populations. These findings support the need for a careful review of existing supplementation schedules and early oral hygiene practices. There is a pressing need for additional analytical epidemiological studies to confirm existing findings and to determine whether other fluoride sources may be associated with enamel fluorosis. Further, since exposure to combinations of individual risk factors has been shown to carry more than merely an additive increase in the risk of fluorosis, these studies must be multifactorial in design. There is also a need for more fluorosis prevalence and severity data to be gathered, so that the development of enamel fluorosis as a public health problem can be assessed, and so that the success of measures implemented to maximize efficacy while minimizing unwanted side-effects can be monitored.

Clinical Evidence of the Role of Pre-eruptive Fluoride in Caries Prevention

Recent clinical and laboratory evidence has suggested that systemic fluoride plays a more minor role in caries inhibition than was previously believed. This paper reviews clinical data on water fluoridation, the topical administration of fluorides, and fluoride supplements in the light of more recent understanding of the disease dental caries. Due to reduced functional usage, erupting teeth tend to accumulate plaque which has cariogenic potential. For this reason, the period from tooth emergence to the establishment of interproximal contact and full occlusion is the most critical for caries initiation. Analyses of clinical data indicate that maximum protection against caries is obtained when teeth erupt into an environment with low concentrations of ionic fluoride. The similarity in caries reductions obtained in water fluoridation studies and long-term studies with topically administered fluoride regimens, including fluoride-containing dentifrices, indicates that the pre-eruptive effect of fluoride is of borderline significance relative to the more significant post-eruptive effect. Water fluoridation and topical fluoride programs are thus important measures for the control of caries at the community level. For the individual, topical application of fluoride is seen as an integral part of caries treatment aimed at arresting progressive caries. Fluoride application is thus considered a supportive therapy, in conjunction with cariogenic plaque control. Daily use of fluoridated dentifrices from tooth eruption is more efficacious than daily use of fluoride supplements from birth.

Water Fluoridation and Fluoride Supplementation: Considerations for the Future

The extensive literature on water fluoridation and fluoride supplementation is discussed, looking critically at the benefits of systemic fluoride availability in the prevention of dental caries and at the adverse factors of enamel fluorosis which can occur from the ingestion of too much fluoride during the period of tooth development. Recommendations are made for the future use of fluorides, emphasizing that water fluoridation is a safe and proven health measure which should be continued. Caution in the use of other fluoride supplementation methods is raised, especially when related to compliance and the use of fluoride supplements which are under the control of the individual. Targeting of children who would benefit from fluorides and additional preventive dental health measures is recommended.

The Future of Water Fluoridation and Other Systemic Fluorides

School and community water fluoridation, salt fluoridation, and use of dietary fluoride supplements have abundant scientific support as effective caries-preventive methods. Because caries has declined greatly in many developed countries from use of topical fluorides, the absolute caries reduction will be considerably smaller when systemic fluoride methods are implemented now than it was 20 to 40 years ago. For countries with most of the population living in cities with communal water supplies, community fluoridation is the most logical approach from the standpoints of cost-effectiveness and total caries-preventive impact. In countries with a mostly rural population without central water supplies, salt fluoridation is more practical. Dietary fluoride supplements can be recommended only for regions where neither water fluoridation nor salt fluoridation is possible, or as a temporary measure. Although divergent views exist concerning the relative caries-preventive effects of pre-eruptive and post-eruptive fluoride administration, the effectiveness of systemic fluoride methods for preventing dental caries remains unchallenged. Persuasive scientific and public health arguments exist to justify implementing and sustaining their use. The future of these methods will be influenced by the findings of new clinical and epidemiological research. Social, political, economic, and educational factors will be of equal, if not greater, importance. Perceptions of the current severity of dental caries as a health problem and of risks associated with preventing the problem may affect the future uses of systemic fluorides more than will recommendations of scientists.

Effectiveness of water fluoridation.

The efficacy of communal water fluoridation in reducing dental caries has been reviewed based on surveys conducted in the last decade of caries prevalence in fluoridated and nonfluoridated communities in the United States as well as in Australia, Britain, Canada, Ireland, and New Zealand. The efficacy is greatest for the deciduous dentition, with a range of 30-60 percent less caries in fluoridated communities. In the mixed dentition (ages 8 to 12), the efficacy is more variable, about 20-40 percent less caries. In adolescents (ages 14-17), it is about 15-35 percent less caries. Current data on caries prevalence in adults and seniors are extremely limited and include several populations living in communities with higher than optimal fluoride levels. For these adults and seniors, a range of 15-35 percent less caries would also apply. Viewed in toto, the current data for children, adolescents, adults and seniors show a consistently and substantially lower caries prevalence in fluoridated communities. For an accurate measurement of the efficacy of water fluoridation in reducing dental caries, it is essential that only persons with a record of continuous or long-term residency in fluoridated versus nonfluoridated areas be included in such assessments. Because of the high geographic mobility in our society and the widespread use of fluoride dentifrices, supplements, and other topical fluoride agents, such comparisons are becoming more difficult to conduct. Accordingly, the effectiveness (rather than the efficacy) of water fluoridation has decreased as the benefits of other forms of fluoride have spread to communities lacking optimal water fluoridation.

Relationship of dental caries and fluorosis to fluoride supplement history in a non-fluoridated sample of schoolchildren.

A random sample of 206 Michigan children, aged from 9 to 13, were examined for fluorosis from a larger group of 2038 children participating in a dental project. Clinical examinations included caries data (DMFS) and assessment of fluorosis by use of the Tooth Surface Index of Fluorosis (TSIF). Separate examiners were used for each index. The response rate of a questionnaire mailed to parents to gather information on residence histories, use of fluoride supplements, and antibiotics was 78%. The prevalence of fluorosis was about 20% among the respondents. Of the 4868 tooth surfaces examined, 9.2% were affected by fluorosis. In all cases, dental fluorosis was judged as mild, with most occurrences on the posterior teeth. No instances of moderate or severe fluorosis were found. The caries experience of respondents was 1.69 +/- 2.73 DMFS. Caries experience does not appear to be significantly related to income, education, or fluoride supplement use. Approximately 52% of respondents were reported to have taken fluoride supplements with various degrees of consistency. Parents' education was positively related to both prevalence of fluorosis (odds ratio = 2.2) and use of fluoride supplements (odds ratio = 2.7). No significant relation was revealed with evidence of fluorosis and use of supplements. This study shows a relatively mild level of dental fluorosis in a sample of children from a non-fluoridated area. Dental fluorosis in this group does not appear to be related to use of fluoride supplements or differences in caries experience.

Guidelines for the use of dietary fluoride supplements in Australia.

A survey in 1988 of brands of fluoride supplements available in a non-fluoridated town in Western Australia, and tablets described in pharmaceutical product registers, revealed that six brands of tablets and one brand of solution (drops) were on the market. Tablets contained 2.2 mg or 1.1 mg NaF; the solution contained 2.2 mg NaF per mL. All products provided age-dose schedules which would give fluoride supplementation at levels greater than the National Health and Medical Research Council guidelines. In one case, infants following the schedule would receive four times the recommended dose for the first two years of life. Compliance with several of the age-dose schedules would be certain to cause significant dental fluorosis. Whether the others caused fluorosis would depend on the quantity of fluoride in the diet, and consumption of fluoride toothpaste. The survey showed a generalized disregard on the part of the ethical pharmaceutical industry for the risk of dental fluorosis, and reveals a need for a voluntary, or legally enforced, code of conduct for manufacturers of fluoride supplements. The value of guidelines which are not monitored is doubtful.

Use of systemic fluoride supplements by North Carolina dentists

This 1984 survey focuses on the use of systemic fluoride supplements by North Carolina dentists. Respondents included all the state's pediatric dentists and general practitioners who assay water supplies before prescribing fluoride supplements, and other randomly selected general practitioners who treat children. Whether practicing in fluoridated or nonfluoridated communities, most dentists prescribed systemic fluoride supplements but only a small number of practitioners assayed water supplies before doing so.

Contribution of fluoride vehicles to change in caries severity in Australian adolescents.

The contribution of a fluoride vehicle to change in caries severity in a population depends on the importance of its association with caries severity and the population's exposure to the vehicle. The present study aimed to quantify population trends in Australian adolescents' exposure to fluoridated water supplies, fluoride supplements and fluoride-containing dentifrice between 1965 and 1978, and conditionally up to 1990; to predict changes in caries severity; and to indicate the change attributable to each fluoride vehicle. At a population level, proportion of lifetime exposure to fluoridated water supplies and market-share held by fluoride-containing dentifrice increased over the period 1965 to 1990. Regular use of fluoride supplements first increased, then decreased over the period. Caries severity was predicted to have decreased markedly for Australian adolescents over the period 1965 to 1990, with the rate of change over the period varying by age. Fluoridated water supplies, followed by fluoride-containing dentifrice contributed most to the change in caries severity.

Amounts of Fluoride in Self-Administered Dental Products: Safety Considerations for Children

With the increased use of various fluoride preparations for caries prevention, all dental personnel should know their potential toxicity and the margins of safety associated with their use. An understanding of the body's mechanisms for handling fluoride provides a rational basis for assessing the possible risks of excessive fluoride ingestion. Five to 10 g of sodium fluoride is considered a certainly lethal dose for a 70-kg adult. One quarter of the certainly lethal dose can be ingested without producing serious acute toxicity and is known as the safely tolerated dose. Comparisons of certainly lethal and safely tolerated doses for commonly used fluoride agents and procedures show that they can be applied with little or no risk of adverse acute effects, as long as they are used judiciously. If their use is abused, there is a risk of illness or even death. If amounts of fluoride close to the certainly lethal dose are ingested, the speed of initiating proper treatment is critical for survival. Vomiting should be induced, if it is not spontaneous; fluoride-binding liquids, such as milk or liquid or gel antacids, administered; and the patient taken to the nearest hospital for emergency care. Frequent ingestion of low but excessive quantities of fluoride during the period of tooth formation can lead to dental fluorosis. Particular concern is warranted for the ingestion of fluoride-containing toothpastes by young children and the inappropriate use of dietary fluoride supplements in communities with sufficient fluoride already present in drinking water.(ABSTRACT TRUNCATED AT 250 WORDS)

Fluoride Supplementation

This statement reviews the rationale for the use of fluoride supplements for infants and children. The concept of fluoridation of water supplies as an effective and cost-beneficial method of reducing caries prevalence in the general population is strongly supported. In the absence of an adequately fluoridated water supply, fluoride supplements should be given to all children. This should begin at about 2 weeks of age; the dosage will depend on the concentration of fluoride in the local water supply. Fluoride-containing dentifrices are an important source of topical fluoride, but it is essential that parents be aware of the danger of excessive fluoride intake and that they teach their children to avoid swallowing toothpaste.

Expansion of the proper use of systemic fluoride supplements

Systemic fluoride supplements, such as tablets and drops, are recommended as alternatives to community and school water fluoridation. Assay of patients' drinking water should be used to determine the water fluoride content. Supplements should be used only when the water fluoride level is found to be deficient. In this way, the appropriate dosage supplement can be determined and prescribed, and unnecessary risks of fluorosis can be avoided. Research has shown that many practitioners prescribe fluoride supplements, although relatively few practitioners assay patients' water supplies. Increased use of water assay and fluoride supplements is warranted if the dental profession is to continue its emphasis on prevention. This increase should be in conjunction with water fluoridation, topical fluorides, and pit and fissure sealants.