Prospective study of the association between fluoride intake and dental fluorosis in permanent teeth

Advances in epidemiological status and pathogenesis of dental fluorosis

Fluoride is commonly consider as a "double-edged sword" because low consumption of fluoride can effectively prevent dental caries, but excessive consumption of fluoride can cause fluorosis. Dental fluorosis (DF) is a characteristic feature of fluorosis in the oral cavity that is manifested as tooth color changes and evident enamel defect. Presently, the pathogenesis of DF remains unclear. Herein, we have summarized the research progress in the pathogenesis and mechanism of DF in the past 5 years.

Fluoride Intake Through Dental Care Products: A Systematic Review

Fluoride (F) is added to many dental care products as well as in drinking water to prevent dental decay. However, recent data associating exposure to F with some developmental defects with consequences in many organs raise concerns about its daily use for dental care. This systematic review aimed to evaluate the contribution of dental care products with regard to overall F intake through drinking water and diet with measurements of F excretion in urine used as a suitable biomarker. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using keywords related to chronic exposure to F in the human population with measurements of F levels in body fluids, 1,273 papers published between 1995 and 2021 were screened, and 28 papers were finally included for data extraction concerning daily F intake. The contribution of dental care products, essentially by toothbrushing with kinds of toothpaste containing F, was 38% in the mean regardless of the F concentrations in drinking water. There was no correlation between F intake through toothpaste and age, nor with F levels in water ranging from 0.3 to 1.5 mg/L. There was no correlation between F intake and urinary F excretion levels despite an increase in its content in urine within hours following exposure to dental care products (toothpastes, varnishes, or other dental care products). The consequences of exposure to F on health are discussed in the recent context of its suspected toxicity reported in the literature. The conclusions of the review aim to provide objective messages to patients and dental professionals worried about the use of F-containing materials or products to prevent initial caries or hypomineralized enamel lesions, especially for young children.

Investigation on Efficient Removal of Fluoride from Ground Water Using Activated Carbon Adsorbents

Groundwater seems to be the most significant natural source of potable water for millions of individuals. Fluoride pollution in groundwater is a big problem in Tamil Nadu’s Dharmapuri area. According to a survey done in a school in the Dharmapuri area, dental and skeletal fluoroses afflict almost 75% of school kids. There is no proven or recommended cost-effective strategy for lowering fluoride levels in the home. This study proposes cost-effective and efficient natural treatment approaches for lowering fluoride levels. In this experiment, fluorides in groundwater are eliminated to a suitable extent utilizing natural adsorbents. Neem stem charcoal (activated carbon), neem leaves powder, dry coconut husk, coconut shell charcoal (activated carbon), and rice husk powder are natural adsorbents. The adsorbents were utilized at different concentrations until the best concentration was found. The ideal concentration removes the bulk of fluoride from groundwater and delivers adequate treatment. People could adopt this cost-effective procedure because just a few components are enough. As per the Bureau of Indian Standards, the concentration should not exceed 1.5 ppm, and it should not be lesser than 1 ppm; keeping this in mind, the neem stem charcoal which has higher efficiency in removing fluoride can be used in extensive environments, but in this selected place, it reduces the concentration even below 1 ppm, which relays below the standard level. As a result, adopting these procedures helps prevent dental and skeletal fluoroses, which is common among young people.

Review of Fluoride Intake and Appropriateness of Current Guidelines

Since the classical epidemiological studies by Dean, it has been known that there should be an optimum level of exposure to fluoride that would be able to provide the maximum protection against caries, with minimum dental fluorosis. The "optimal" daily intake of fluoride for children (0.05-0.07 mg per kilogram bodyweight) that is still accepted worldwide was empirically determined. In the present review, we discuss the appropriateness of the current guidance for fluoride intake, in light of the windows of susceptibility to caries and fluorosis, the modern trends of fluoride intake from multiple sources, individual variations in fluoride metabolism, and recent epidemiological data. The main conclusion is that it is very difficult to think about a strict recommendation for an "optimal" range of fluoride intake at the individual level in light of existing knowledge of 1) the mechanisms of action of fluoride to control caries, 2) the mechanisms involved in dental fluorosis development, 3) the distinct factors that interfere in the metabolism of fluoride, and 4) the windows of susceptibility to both dental caries and fluorosis development. An "optimal" range of fluoride intake is, however, desirable at the population level to guide programs of community fluoridation, but further research is necessary to provide additional support for future decisions on guidance in this area. This list includes the effect of factors affecting fluoride metabolism, clinical trials on the effectiveness of low-fluoride dentifrices to prevent caries in the primary dentition, and validation of biomarkers of exposure to fluoride.

Systemic Effects (Risks) of Water Fluoridation

Abstract Since the 1950s, the benefits and risks of fluoridated water use have been debated worldwide. In the past, it was considered that the systemically ingested fluoride would exert its primary preventive effect after being incorporated into the enamel as fluorapatite, making the enamel more resistant to the caries process; however, it is now recognized that the main effect of water fluoridation is local and post eruptive. On the other hand, irrespective of the caries decline reported worldwide, the anticaries benefit of water fluoridation continues to be observed even in developed countries. Regarding the risks, water fluoridation is considered an acceptable community-based method for fluoride delivery, because the risk of developing dental fluorosis lesions due to the ingestion of fluoride during the enamel formation period has been deemed acceptable when contrasted to the anticaries benefits of fluoride. However, the use of fluoride in water to control caries has created a controversy due to data associating water fluoridation as the cause of some systemic diseases. Therefore, the aim of this descriptive review was to discuss the systemic effects (risks) of water fluoridation use.

Exposição a fluoreto por crianças na faixa etária crítica para fluorose dentária, residentes no semiárido brasileiro

Resumo Há uma preocupação com o aumento da prevalência de fluorose dentária, que depende da dose de fluoreto (F) a que as crianças são submetidas durante a formação dos dentes. A temperatura ambiental afeta a ingestão de água e, portanto, seria importante avaliar se as crianças que vivem em uma região de clima semiárido estão expostas a uma dose excessiva de F. Assim, o objetivo do presente estudo foi determinar a dose total de F a que as crianças são expostas durante a idade crítica para a fluorose dentária, tendo dieta (água e alimentos) e dentifrício como fontes de F, em uma região de clima semiárido no Brasil. Metodologia: foram selecionadas 26 crianças com idade de 25,2 ± 9,1 meses, residentes em Feira de Santana-BA. Foram coletadas amostras de dieta-duplicada, água, produtos de escovação e dentifrícios. A concentração de F foi determinada após o devido preparo das amostras, utilizando um eletrodo específico. Resultados: a média e o desvio padrão de dose (mg F / kg / dia) em função da dieta, dentifrício e total foram, respectivamente: 0,016 ± 0,010; 0,030 ± 0,039 e 0,047 ± 0,043. Conclusões: as crianças avaliadas, residentes em uma região de clima semiárido, não estão expostas a uma dose de risco de fluorose dentária.

Impact of caries and dental fluorosis on oral health-related quality of life: a cross-sectional study in schoolchildren receiving water naturally fluoridated at above-optimal levels

PURPOSE

The purpose of this study was to evaluate the impact of caries and fluorosis on oral health-related quality of life (OHRQoL) among schoolchildren living in areas with high concentrations of fluoride in water.

METHODS

Five hundred and twenty-four schoolchildren (8-12 year olds) residing in rural communities in central Mexico were examined for oral hygiene, caries (International Caries Detection and Assessment System, ICDAS II), and fluorosis (Thylstrup and Fejerskov Index, TFI). OHRQoL was evaluated with the Child Perceptions Questionnaire for two age groups (CPQ_8-10 and CPQ_11-14). Generalized structural equation models were constructed for data analysis.

RESULTS

Overall prevalence of caries was 88.5% and fluorosis 46.9%. In the group of 8-10 year olds, 48% of the children had advanced carious lesions in primary or permanent teeth (ICDAS ≥4), 22.6% had moderate/severe fluorosis, and 59.9% of children had an impact on OHRQoL. Schoolchildren with ICDAS ≥4 were more likely [OR = 1.75, (95% CI 1.34-2.28)] to suffer a negative impact on OHRQoL. In the group of 11-12 year olds, 19.9% of children had advanced carious lesions and 23.2% showed moderate/severe fluorosis; 67.3% of children reported had an impact on OHRQoL. Children 11-12 year olds with fluorosis (TFI ≥4) [OR = 2.39 (95% CI 2.12-2.69)], caries (ICDAS ≥4) [OR = 2.18 (95% CI 2.13-2.24)], and low brushing frequency [OR = 2.04 (95% CI 1.21-3.44)] were more likely to have deterioration on OHRQoL.

CONCLUSION

A negative impact on OHRQoL was observed in children with caries and fluorosis.

CLINICAL RELEVANCE

Deterioration on OHRQoL found in children as a sequel of caries and fluorosis should be considered when designing health policies leading to prevention and effective health promotion programs and incorporated to clinical guidelines for timely dental treatment.

Impact of dental fluorosis on the quality of life of children and adolescents

INTRODUCTION: Dental fluorosis is a disturbance of high prevalence caused by the ingestion of fluoride ions present mainly in toothpaste. Preventive measures to avoid it are still controversial. Thus, knowing the impact that fluorosis can cause on the population's quality of life it is important for planning public health policies.OBJECTIVE: To evaluate the impact of dental fluorosis on the quality of life of children and adolescents.MATERIAL AND METHOD: We studied 300 subjects aged 8 to 12 years divided into 4 groups: children (8-10 years) and adolescents (10 to 12 years) with and without fluorosis. The diagnosis of fluorosis was performed according to the index Thylstrup and Fejerskov and quality of life was evaluated using Child Perceptions Questionnaire 8-10 and 11-14. The socio-demographic characteristics of the patients were also evaluated. For inclusion in the sample, selected patients should present eight permanent incisors with crowns fully erupted. Patients who had extensive restorations, fractured teeth, other dental enamel defects and who wore braces were excluded.RESULT: Fluorosis was present in 64.7% of the patients analyzed and in most cases (80.3%) was mild or very mild. In children, the average overall score of the questionnaire was 15.9 for the group without fluorosis and 18.3 for the group with fluorosis (p = 0.255). The teenagers' score in the group without fluorosis was 26.1, while the group with fluorosis was 22.7 (p = 0.104).CONCLUSION: Dental fluorosis caused impact on the quality of life of the population analyzed only in the functional domain.

Estimated fluoride doses from toothpastes should be based on total soluble fluoride

The fluoride dose ingested by young children may be overestimated if based on levels of total fluoride (TF) rather than levels of bioavailable fluoride (total soluble fluoride—TSF) in toothpaste. The aim of the present study was to compare doses of fluoride intake based on TF and TSF. Fluoride intake in 158 Brazilian children aged three and four years was determined after tooth brushing with their usual toothpaste (either family toothpaste (n = 80) or children’s toothpaste (n = 78)). The estimated dose (mg F/day/Kg of body weight) of TF or TSF ingested was calculated from the chemical analysis of the toothpastes. Although the ingested dose of TF from the family toothpastes was higher than that from the children’s toothpastes (0.074 ± 0.007 and 0.039 ± 0.003 mg F/day/Kg, respectively; p < 0.05), no difference between types of toothpaste was found regarding the ingested dose based on TSF (0.039 ± 0.005 and 0.039 ± 0.005 mg F/day/Kg, respectively; p > 0.05). The fluoride dose ingested by children from toothpastes may be overestimated if based on the TF of the product. This finding suggests that the ingested dose should be calculated based on TSF. Dose of TSF ingested by children is similar whether family or children’s toothpaste is used.

Association between socioeconomic factors and the choice of dentifrice and fluoride intake by children

It is questionable whether socioeconomic factors influence the choice of marketed children’s dentifrices and whether these products are associated with greater fluoride (F) intake in children. The present cross-sectional study involving 197 children (mean age: 40.98 ± 6.62 months) was carried out in Montes Claros, Brazil. Parents completed a questionnaire on socioeconomic status and the tooth brushing habits of their children. The children brushed their teeth and saliva residues were collected for F analysis. F intake from dentifrice was determined with an ion-specific electrode. Univariate analysis and logistic regression were used to test whether the type of dentifrice (children’s or family) and F dose (<0.05 and ≥0.05 mg F/Kg of body weight/day) were associated with the independent variables (p < 0.05). No differences were found between children’s and family dentifrices regarding daily F intake (0.046 and 0.040 mg F/Kg/day, respectively; p = 0.513). The following were strong predictors for the use of a children’s dentifrice: studying at a private kindergarten (OR: 6.89; p < 0.001); age that the child begun to tooth brush <2 years (OR: 2.93; p = 0.041), and the interaction between the variables “use of the same dentifrice as parents” and “type of tooth brush used” (OR: 27.20; p < 0.001). “The amount of dentifrice used” and “frequency of tooth brushing” (p ≤ 0.004) had a statistically and synergistic effect over the daily F dose. The present study found a social influence over the choice of dentifrice: children with a high socioeconomic status tend to use a children’s dentifrice. The amount of dentifrice used can strongly increase the risk of exposure to higher doses of F, regardless of the type of dentifrice.

Qualidade da água para consumo humano e concentração de fluoreto

O artigo visa analisar a concentração de fluoreto na água para consumo humano, considerando o balanço entre benefícios e riscos à saúde, e produzir subsídios para atualização da legislação brasileira. Estudos de revisão sistemática, documentos oficiais e dados meteorológicos foram examinados. As temperaturas nas capitais brasileiras indicam que o fluoreto deveria variar de 0,6 a 0,9 mg/L para prevenir cárie dentária. Concentração de fluoreto natural de 1,5 mg/L é tolerável para consumo no Brasil se não houver tecnologia de custo-benefício aceitável para ajuste/remoção do seu excesso. A ingestão diária de água com fluoreto em concentração > 0,9 mg/L representa risco à dentição em menores de oito anos de idade e os consumidores deveriam ser expressamente informados desse risco. Considerando a expansão do programa nacional de fluoretação da água para regiões de clima tipicamente tropical, deve-se revisar a Portaria 635/75, relacionada ao fluoreto adicionado às águas de abastecimento público.

Comparison between observed children's tooth brushing habits and those reported by mothers

Background

Information bias can occur in epidemiological studies and compromise scientific outcomes, especially when evaluating information given by a patient regarding their own health. The oral habits of children reported by their mothers are commonly used to evaluate tooth brushing practices and to estimate fluoride intake by children. The aim of the present study was to compare observed tooth-brushing habits of young children using fluoridated toothpaste with those reported by mothers.

Methods

A sample of 201 mothers and their children (aged 24-48 months) from Montes Claros, Brazil, took part in a cross-sectional study. At day-care centres, the mothers answered a self-administered questionnaire on their child's tooth-brushing habits. The structured questionnaire had six items with two to three possible answers. An appointment was then made with each mother/child pair at day-care centres. The participants were asked to demonstrate the tooth-brushing practice as usually performed at home. A trained examiner observed and documented the procedure. Observed tooth brushing and that reported by mothers were compared for overall agreement using Cohen's Kappa coefficient and the McNemar test.

Results

Cohen's Kappa values comparing mothers' reports and tooth brushing observed by the examiner ranged from poor-to-good (0.00-0.75). There were statistically significant differences between observed tooth brushing habits and those reported by mothers (p < 0.001). When observed by the examiner, the frequencies of dentifrice dispersed on all bristles (35.9%), children who brushed their teeth alone (33.8%) and those who did not rinse their mouths during brushing (42.0%) were higher than those reported by the mothers (12.1%, 18.9% and 6.5%, respectively; p < 0.001).

Conclusions

In general, there was low agreement between observed tooth brushing and mothers' reports. Moreover, the different methods of estimation resulted in differences in the frequencies of tooth brushing habits, indicative of reporting bias. Data regarding children's tooth-brushing habits as reported by mothers should be considered with caution in epidemiological surveys on fluoridated dentifrice use and the risk of dental fluorosis.

Effect of discontinuation of fluoride intake from water and toothpaste on urinary excretion in young children

As there is no homeostatic mechanism for maintaining circulating fluoride (F) in the human body, the concentration may decrease and increase again when intake is interrupted and re-started. The present study prospectively evaluated this process in children exposed to F intake from water and toothpaste, using F in urine as a biomarker. Eleven children from Ibiá, Brazil (with sub-optimally fluoridated water supply) aged two to four years who regularly used fluoridated toothpaste (1,100 ppm F) took part in the study. Twenty-four-hour urine was collected at baseline (Day 0, F exposure from water and toothpaste) as well as after the interruption of fluoride intake from water and dentifrice (Days 1 to 28) (F interruption) and after fluoride intake from these sources had been re-established (Days 29 to 34) (F re-exposure). Urinary volume was measured, fluoride concentration was determined and the amount of fluoride excreted was calculated and expressed in mg F/day. Urinary fluoride excretion (UFE) during the periods of fluoride exposure, interruption and re-exposure was analyzed using the Wilcoxon test. Mean UFE was 0.25 mg F/day (SD: 0.15) at baseline, dropped to a mean of 0.14 mg F/day during F interruption (SD: 0.07; range: 0.11 to 0.17 mg F/day) and rose to 0.21 (SD: 0.09) and 0.19 (SD: 0.08) following F re-exposure. The difference between baseline UFE and the period of F interruption was statistically significant (p<0.05), while the difference between baseline and the period of F re-exposure was non-significant (p>0.05). The findings suggest that circulating F in the body of young children rapidly decreases in the first 24 hours and again increases very fast after discontinuation and re-exposure of F from water and toothpaste.

Fluoride consumption and its impact on oral health

OBJECTIVE

The purpose of this study was to evaluate caries and dental fluorosis among Mexican preschoolers and school-aged children in a non-endemic zone for fluorosis and to measure its biological indicators.

METHODS

DMFT, DMFS, dmft, dmfs, and CDI indexes were applied. Fluoride urinary excretion and fluoride concentrations in home water, table salt, bottled water, bottled drinks, and toothpaste were determined.

RESULTS

Schoolchildren presented fluorosis (CDI = 0.96) and dental caries (DMFT = 2.64 and DMFS = 3.97). Preschoolers presented dmft = 4.85 and dmfs = 8.80. DMFT and DMFS were lower in children with mild to moderate dental fluorosis (DF). Variable fluoride concentrations were found in the analyzed products (home water = 0.18-0.44 ppm F, table salt = 0-485 ppm F, bottled water = 0.18-0.47 ppm F, juices = 0.08-1.42 ppm F, nectars = 0.07-1.30 ppm F, bottled drinks = 0.10-1.70 ppm F, toothpaste = 0-2,053 ppm F). Mean daily fluoride excretion was 422 ± 176 μg/24 h for schoolchildren and 367 ± 150 μg/24 h for preschoolers.

CONCLUSIONS

Data from our study show that, despite values of excretion within an optimal fluoride intake range, the prevalence of caries was significant in both groups, and 60% of the 11- to 12-year-old children presented with dental fluorosis. In addition, variable fluoride concentrations in products frequently consumed by children were found.

Topical fluoride as a cause of dental fluorosis in children

BACKGROUND

For many years, topical use of fluorides has gained greater popularity than systemic use of fluorides. A possible adverse effect associated with the use of topical fluoride is the development of dental fluorosis due to the ingestion of excessive fluoride by young children with developing teeth.

OBJECTIVES

To describe the relationship between the use of topical fluorides in young children and the risk of developing dental fluorosis.

SEARCH STRATEGY

Electronic search of the Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE, EMBASE, BIOSIS, Dissertation Abstracts and LILACS/BBO. Reference lists from relevant articles were searched. Date of the most recent searches: 9th March 09.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, cohort studies, case-control studies and cross-sectional surveys, in which fluoride toothpastes, mouthrinses, gels, foams, paint-on solutions, and varnishes were compared to an alternative fluoride treatment, placebo or no intervention group. Children under the age of 6 years at the time topical fluorides were used.

DATA COLLECTION AND ANALYSIS

Data from all included studies were extracted by two review authors. Risk ratios for controlled, prospective studies and odds ratios for case-control studies or cross-sectional surveys were extracted or calculated. Where both adjusted and unadjusted risk ratios or odds ratios were presented, the adjusted value was included in the meta-analysis.

MAIN RESULTS

25 studies were included: 2 RCTs, 1 cohort study, 6 case-control studies and 16 cross-sectional surveys. Only one RCT was judged to be at low risk of bias. The other RCT and all observational studies were judged to be at moderate to high risk of bias. Studies were included in four intervention/exposure comparisons. A statistically significant reduction in fluorosis was found if brushing of a child's teeth with fluoride toothpaste commenced after the age of 12 months odds ratio 0.70 (random-effects: 95% confidence interval 0.57 to 0.88) (data from observational studies). Inconsistent statistically significant associations were found between starting using fluoride toothpaste/toothbrushing before or after the age of 24 months and fluorosis (data from observational studies). From the RCTs, use of higher level of fluoride was associated with an increased risk of fluorosis. No significant association between the frequency of toothbrushing or the amount of fluoride toothpaste used and fluorosis was found.

AUTHORS' CONCLUSIONS

There should be a balanced consideration between the benefits of topical fluorides in caries prevention and the risk of the development of fluorosis. Most of the available evidence focuses on mild fluorosis. There is weak unreliable evidence that starting the use of fluoride toothpaste in children under 12 months of age may be associated with an increased risk of fluorosis. The evidence for its use between the age of 12 and 24 months is equivocal. If the risk of fluorosis is of concern, the fluoride level of toothpaste for young children (under 6 years of age) is recommended to be lower than 1000 parts per million (ppm).More evidence with low risk of bias is needed. Future trials assessing the effectiveness of different types of topical fluorides (including toothpastes, gels, varnishes and mouthrinses) or different concentrations or both should ensure that they include an adequate follow-up period in order to collect data on potential fluorosis. As it is unethical to propose RCTs to assess fluorosis itself, it is acknowledged that further observational studies will be undertaken in this area. However, attention needs to be given to the choice of study design, bearing in mind that prospective, controlled studies will be less susceptible to bias than retrospective and/or uncontrolled studies.

Agreement in the diagnosis of dental fluorosis in central incisors performed by a standardized photographic method and clinical examination

The aim of this study was to assess agreement in the diagnosis of dental fluorosis performed by a standardized digital photographic method and a clinical examination (gold standard). 49 children (aged 7-9 years) were clinically evaluated by a trained examiner for the assessment of dental fluorosis. Central incisors were evaluated for the presence or absence of dental fluorosis and were photographed with a digital camera. Photographs were presented to three pediatric dentists, who examined the images. Data were analyzed using Cohen's kappa and validity values. Agreement in the diagnosis performed by the photographic method and clinical examination was good (0.67) and accuracy was 83.7%. The prevalence of dental fluorosis was reported to be higher in the clinical examination (49%) compared with the photographic method (36.7%). The photographic method presented higher specificity (96%) than sensitivity (70.8%), a positive predictive value (PPV) of 94.4% and a negative predictive value (NPV) of 77.4%. The diagnosis of dental fluorosis performed using the photographic method presented high specificity and PPV, which indicates that the method is reproducible and reliable for recording dental fluorosis.

Dietary Fluoride Intake by Children Receiving Different Sources of Systemic Fluoride

There has been no comparison of fluoride (F) intake by pre-school children receiving more traditional sources of systemic F. The aim of this study was to estimate the dietary F intake by children receiving F from artificially fluoridated water (AFW-Brazil, 0.6–0.8 mg F/L), naturally fluoridated water (NFW-Brazil, 0.6–0.9 mg F/L), fluoridated salt (FS-Peru, 180–200 mg F/Kg), and fluoridated milk (FM-Peru, 0.25 mg F). Children (n = 21–26) aged 4–6 yrs old participated in each community. A non-fluoridated community (NoF) was evaluated as the control population. Dietary F intake was monitored by the “duplicate plate” method, with different constituents (water, other beverages, and solids). F was analyzed with an ion-selective electrode. Data were tested by Kruskall-Wallis and Dunn’s tests (p < 0.05). Mean (± SD) F intake (mg/Kg b.w./day) was 0.04 ± 0.01b, 0.06 ± 0.02a,b, 0.05 ± 0.02a,b, 0.06 ± 0.01a, and 0.01 ± 0.00c for AFW/NFW/FS/FM/NoF, respectively. The main dietary contributors for AFW/NFW and FS/FM/NoF were water and solids, respectively. The results indicate that the dietary F intake must be considered before a systemic method of fluoridation is implemented.

Comparison of a dietary survey and the duplicate plate method for determining dietary fluoride ingested by young children: a pilot study

BACKGROUND

Investigators have attempted to establish the diet's contribution to the total body burden of fluoride in response to a reported trend towards an increase in fluoride intake.

AIM

The aim of this study was to compare the suitability of two methods to collect dietary data for fluoride intake assessment.

DESIGN

Assessments were made in 12 children using the duplicate plate and dietary diary methods following a randomized cross-over design. Foods and beverages were analysed for fluoride, and total fluoride intake per day was calculated. Results from each method were compared.

RESULTS

Mean beverage fluoride intake was estimated at 316 +/- 120 and 422 +/- 195 microg/day utilizing the diary and duplicate plate methods, respectively. Mean food fluoride intake was estimated at 188 +/- 48 microg/day using the diary, whereas it was 130 +/- 41 microg using the duplicate plate method. Total fluoride intake was 504 +/- 138 and 552 +/- 192 microg/day utilizing the diary and duplicate methods. Large variations in daily fluoride intake from both beverages and food were observed between and within children.

CONCLUSIONS

Both methods had inherent shortcomings and sources of error. The duplicate method was more labour intensive and costly; however, the diary method required a large number of assumptions. A combination of both methods seems to be most suitable to obtain reliable data.