Fluoride intake by Brazilian children from two communities with fluoridated water

OBJECTIVES: To determine total daily fluoride intake by young children from two communities in a developing country. METHODS: Fluoride intake from diet and dentifrice was determined for 71 Brazilian children, aged 19-38 months, living in two communities with fluoridated water (0.6-0.8 ppm). The children from Piracicaba attended a full-time day care centre but those from Ibiá did not. Fluoride ingested during tooth brushing was determined, and 'duplicate-plate' samples of all foods and beverages ingested during a 2-day period were collected from which fluoride for analysis was extracted by hexamethyldisiloxane (HMDS) microdiffusion. The amount of fluoride ingested (mg F/kg body weight/day) from the diet and dentifrice and the combined fluoride intake were calculated. A limit of 0.05-0.07 mg F/kg body weight/day was considered as the safe threshold for fluoride exposure. RESULTS: The children from Ibiá had lower amounts of fluoride in their diets than those from Piracicaba (P < 0.05); no differences in the amount of fluoride ingested from dentifrice were found between the communities. In both communities, the daily fluoride intake from dentifrice was higher than that from the diet (P < 0.05). Most of the children from both communities were exposed to a combined dose (diet + dentifrice) of fluoride above the risk threshold for dental fluorosis. CONCLUSION: The data suggest that fluoride intake from diet depends on living conditions, and measures should be implemented to reduce the fluoride intake of these Brazilian children.     

The fluoride content of foods and beverages from negligibly and optimally fluoridated communities

In the spring of 1996, foods and beverages most commonly consumed by adolescents were analyzed for fluoride as part of a larger investigation. These foods were selected by interviewing 711 adolescents, 12-14 years of age, who were long-time residents of either an optimally or negligibly fluoridated community. The brand names of the identified foods and beverages most commonly purchased were determined by interviews with the parents. A total of 441 brand-name food and beverage items were purchased from both communities and were individually analyzed for fluoride. These analyses were done in order to estimate the fluoride content of various kinds of foods and beverages and to determine whether or not there was a significant difference between the two communities in the amount of fluoride ingested from these dietary sources. The food and beverage items were classified into dietary groups based on US Department of Agriculture (USDA) guidelines. Overall, the fluoride content of the sampled foods and beverages was low. In addition, there was no significant difference in the fluoride content of the same pre-packaged or ready-to-eat food or beverage items purchased in the two communities. However, a significant difference was found between the two communities in the fluoride content of fountain beverages and in cooked or reconstituted foods prepared using local water from the respective communities. Based on these results, we have estimated the mean daily, dietary fluoride intake for 3-5-year-old children who are more susceptible to developing dental fluorosis.     

Fluoride intake from foods,beverages and dentifrice by children in Mexico

OBJECTIVES: This investigation monitored fluoride ingestion in Mexican children who were susceptible to developing dental fluorosis. METHODS: Total fluoride intake, from dietary and toothpaste samples, was determined in 15-36-month-old children from Mexico City and Veracruz, Mexico. A duplicate plate technique was used. Plasma fluoride levels were also determined in this group of children. RESULTS: The children ingested a mean (+/-SD) of 0.20 +/- 0.08 and 0.18 +/- 0.07 mg fluoride/kg/day, in Mexico City and Veracruz, respectively. There was no statistically significant difference between the fluoride ingested by children in the two cities (P > 0.9). Plasma from children in Mexico City and Veracruz contained a mean of 1.30 +/- 0.81 and 0.87 +/- 0.72 micro mol fluoride/l, respectively, and these values were not significantly different. CONCLUSIONS: Our results lead to the conclusion that mean fluoride ingested from the combination of foods and beverages was within the proposed safe threshold for fluoride intake of 0.05-0.07 mg F/kg/day. Most of the fluoride intake by these children was derived from the ingestion of fluoridated toothpaste. When all sources of ingested fluoride were added and total fluoride intake was calculated, the children, both in Mexico City and Veracruz, were ingesting amounts of fluoride well above the upper limits of the proposed safe threshold for fluoride intake.     

Fluoride concentration of bottled water, tap water, and fluoridated salt from two communities in Mexico

AIM: To determine fluoride levels in bottled water, tap water, and fluoridated salt from two communities in Mexico. DESIGN: Stratified random collection of water and salt samples from Mexico City and Veracruz, Mexico for fluoride analysis. METHODS: Samples were analysed using a combination fluoride ion-specific electrode. Results were compared using Student's t-test and mixed-model ANOVA. Water fluoride values were compared by type, community and collection area; salt fluoride values were compared by community and collection area. RESULTS: 197 tap water samples, 133 bottled water samples and 20 fluoridated salt samples were collected. The mean (+/- SD) fluoride content for all tap water was 0.20 +/- 0.17 microg F/g (ranging from 0.01 to 0.88 microg F/g) and 0.24 +/- 0.24 microg F/g for all bottled water (ranging from 0.01 to 2.80 microg F/g). This difference was not statistically significant. When results were analysed by city, the difference between tap water samples was statistically significant. Ten bottled water samples contained more than negligible fluoride (ranging from 0.7-2.8 microg F/g). Mean salt fluoride content was 230.0 +/- 49.8 microg F/g, which was within governmental regulation levels. CONCLUSION: Some water samples had amounts of fluoride exceeding the maximum recommended levels. Salt fluoride levels were within regulation limits. Monitoring of fluoride content of both bottled and tap water is strongly advised.     

Factors influencing fluoride ingestion from dentifrice by children

Kobayashi CAN, Belini MR, Italiani FM, Pauleto ARC, Julianelli de Araújo J, Tessarolli V, Grizzo LT, Pessan JP, Machado MAAM, Buzalaf MAR. Factors influencing fluoride ingestion from dentifrice by children. Community Dent Oral Epidemiol 2011; 39: 426–432. © 2011 John Wiley & Sons A/S Abstract – Objective: This study assessed the percentage of the amount of dentifrice loaded onto the toothbrush that is ingested by children, taking into account age, the amount of dentifrice used during toothbrushing, and the dentifrice flavor. Methods: The sample consisted of 155 children of both genders attending public kindergartens and schools in Bauru, Brazil, divided into 5 groups (n = 30–32) of children aged 2, 3, 4, 5 and 6 years old. The dentifrices used were Sorriso? (1219 ppm F, peppermint‐flavored) and Tandy? (959 ppm F, tutti‐frutti‐flavored). The assessment of fluoride intake from dentifrices was carried out six times for each child, using 0.3, 0.6, and 1.2 g of each dentifrice, following a random, crossover distribution. Brushing was performed by the children or their parents/caregivers according to the home habits and under the observation of the examiner. Fluoride present in the expectorant and on toothbrush was analyzed with an ion‐specific electrode after HMDS‐facilitated diffusion. Fluoride ingestion was indirectly derived. Results were analyzed by 3‐way repeated‐measures anova and Tukey’s tests (P < 0.05) using the percent dentifrice ingested as response variable. Results: Age and percent dentifrice ingested for both dentifrices, and the three amounts used were inversely related (P < 0.0001). Percent dentifrice ingested was significantly higher after the use of Tandy? under all conditions of the study when compared with Sorriso? (P < 0.0001). Significant differences were observed when brushing with 0.3 g when compared with 1.2 g, for both dentifrices tested (P < 0.05). Conclusions: The results indicate that all variables tested must be considered in preventive measures aiming to reduce the amount of fluoride ingested by young children.     

Fluoride ingestion from food items and dentifrice in 2–6-year-old Brazilian children living in a fluoridated area using a semiquantitative food frequency questionnaire

Abstract – Objectives: The aim of this study was to evaluate the fluoride intake of 2–6‐year‐old Brazilian children using a semiquantitative food frequency questionnaire (FFQ) which also estimated fluoride intake from dentifrice. Methods: The FFQ was previously validated through application to 78 2–6‐year‐old Brazilian children and then administered to 379 children residing in an optimally fluoridated community in Brazil (Bauru, State of São Paulo). The FFQ was applied to the parents and used to estimate the food intake of the children. The constituents of the diet were divided into solids, water and other beverages. The fluoride content of the diet items was analyzed with the fluoride electrode. The questionnaire also estimated fluoride intake from dentifrice. Results: The average (±SD) fluoride intake from solids, water, other beverages and dentifrice was 0.008 ± 0.005; 0.011 ± 0.004; 0.009 ± 0.014 and 0.036 ± 0.028 mg F/kg body weight/day, respectively, totalizing 0.064 ± 0.035 mg F/kg body weight/day. The dentifrice and the diet contributed with 56.3% and 43.7% of the daily fluoride intake, respectively. Among the children evaluated, 31.2% are estimated to have risk to develop dental fluorosis (intake>0.07 mg F/kg body weight/day). Conclusions: The dentifrice was the main source of fluoride intake by the children evaluated. However, the fluoride concentration in food items also significantly contributed to the daily ingestion by 2–6‐year‐old children. The questionnaire used seems to be a promising alternative to duplicate diet to estimate the fluoride intake at this age range and may have potential to be used in broad epidemiological surveys.     

Fluoride ingestion from toothpaste: fluoride recovered from the toothbrush, the expectorate and the after-brush rinses

Abstract -  Objectives: The aim of this study was to determine the effects of rinsing and spitting on fluoride ingestion from toothpaste during normal oral-hygiene procedures of younger children, and hence to make recommendations on rinsing during toothbrushing. Methods: The brushing habits of 166 Dutch and 185 Irish children between 1.5 and 3.5 years were observed during home visits. The weight of the toothpaste tube was determined before and after use. After brushing, the toothbrush and any associated expectorate and rinses, combined with any toothpaste spilled during the brushing procedures, were collected. The amounts of fluoride retained on the toothbrush and in the associated expectorate and rinses were measured. Results: Over 90% of the Dutch children used a special toddlers' toothpaste with ≤500 ppm F. Eleven per cent of the younger (<2.5 years) Dutch children and 22% of the older children rinsed after brushing. Of the Irish children approximately 52% used a children's toothpaste containing around 500 ppm F. Of the younger Irish children 31% spat without rinsing, while another 31% rinsed during or after brushing. For the older Irish children, these percentages were 14 and 70%, respectively. On average, 22% of the fluoride dispensed on the toothbrush was retained on the brush after brushing irrespective of the rinsing and spitting behaviour of the children. The maximum ingestible amount of fluoride from toothpaste assuming no rinsing or spitting was calculated. Conclusions: Fluoride ingestion from toothpaste is significantly reduced by rinsing and/or spitting during toothbrushing. Recommendations that younger children use small amounts of toothpaste (< 0.5 g) and that children using toothpaste with ≥ 1000 ppm F rinse their mouths after brushing continue to be valid.     

Development of a standardized method for comparing fluoride ingested from toothpaste by 1.5-3.5-year-old children in seven European countries. Part 2: Ingestion results

Abstract -  Objectives: To develop a standardized method for measuring the variables affecting fluoride ingestion from toothpaste in young children between the ages of 1.5 and 3.5 years, and to use the method at seven European sites. Methods: Random samples of children were invited to take part in the study. Parents who gave consent were visited at home. The children brushed their teeth using the toothpaste brand and toothbrush type currently in use. The difference between the fluoride dispensed onto the toothbrush and the fluoride recovered after accounting for losses was deemed to be the fluoride ingested. Details of other oral health-care habits were collected by questionnaire. For each child, the fluoride concentration of the toothpaste used was measured in the laboratory, from which an estimate of total daily fluoride ingestion was made. Results: There was considerable variation between countries in the types of toothpaste used and in the amounts of toothpaste applied and ingested. The amount of fluoride ingested ranged from 0.01 to 0.04 mg fluoride per kg of body weight per day. Conclusion: The amount of fluoride ingested that is likely to be a risk factor for the development of dental fluorosis during tooth formation is equivocal and was found to vary widely between European countries. There appears to be a need for clearer health messages regarding the use of fluoridated toothpaste by young children.     

Development of a standardized method for comparing fluoride ingested from toothpaste by 1.5-3.5-year-old children in seven European countries. Part 1: Field work

Abstract -  Objectives: To develop a standardized method for measuring the variables affecting fluoride ingestion from toothpaste in young children between the ages of 1.5 and 3.5 years, and to use the method at seven European sites. Methods: Random samples of children were invited to take part in the study. Parents who gave consent were visited at home. The children brushed their teeth using the toothpaste brand and toothbrush type currently in use. Variables measured were: type of toothpaste used, fluoride concentration of toothpaste used, weight of toothpaste used, frequency of brushing and body weight of the child. Results: It was not possible to follow the agreed protocol in all seven countries and in three countries appropriate alternative methods were employed. There was considerable variation between countries in the variables investigated. Use of children's toothpaste ranged from 69% in Ireland to 98% in Portugal. In the Netherlands up to 60% of the children were using toothpaste containing <400 ppm F and in Finland up to 27% of children were using toothpaste containing >1200 ppm F. Over half of the children used <0.25 g of toothpaste per brushing and the majority of children brushed once or twice per day. Conclusion: Although adherence to the agreed protocol was not possible at all study sites there was a clear picture of considerable variation in the oral hygiene practices of young children throughout Europe.     

Fluoride intake and prevalence of dental fluorosis: trends in fluoride intake with special attention to infants

BACKGROUND: Although the predominant beneficial effect of fluoride occurs locally in the mouth, the adverse effect, dental fluorosis, occurs by the systemic route. The caries attack rate in industrialized countries, including the United States and Canada, has decreased dramatically over the past 40 years. However, the prevalence of dental fluorosis in the United States has increased during the last 30 years both in communities with fluoridated water and in communities with nonfluoridated water. Dental fluorosis is closely associated with fluoride intake during the period of tooth development. METHODS: We reviewed the major changes in infant feeding practices that have occurred since 1930 and the changes in fluoride intakes by infants and young children associated with changes in feeding practices. RESULTS AND CONCLUSIONS: Based on this review, we conclude that fluoride intakes of infants and children have shown a rather steady increase since 1930, are likely to continue to increase, and will be associated with further increase in the prevalence of enamel fluorosis unless intervention measures are instituted. RECOMMENDATIONS: We believe the most important measures that should be undertaken are (1) use, when feasible, of water low in fluoride for dilution of infant formulas; (2) adult supervision of toothbrushing by children younger than 5 years of age; and (3) changes in recommendations for administration of fluoride supplements so that such supplements are not given to infants and more stringent criteria are applied for administration to children.     

Fluoride supplements: current effectiveness, side effects, and recommendations

Abstract – A critical review of the literature was conducted to determine the current effectiveness of fluoride supplements in caries prevention and their role as risk factors for dental fluorosis. Use of fluoride supplements by young children is idiosyncratic and all of the studies which investigated the effectiveness of this regimen suffered from a significant drop in the number of participants receiving daily supplements. The scientific evidence supports the efficacy of fluoride supplements in caries prevention but there is weaker support for their effectiveness. Fluoride supplements are a risk factor for dental fluorosis. though their contribution to the increase in fluorosis prevalence is less than that of water fluoridation and fluoridated dentifrices because of their more limited and shorter use. There is also evidence that fluoride supplements are used inappropriately in fluoridated areas. The availability of optimal levels of fluorides in beverages in non-fluoridated communities raises the question of whether fluoride supplements are needed in the 1990_s, and whether it is time to consider the total fluoride intake not only from water but also from foods, beverages, and dentifrices, when recommending supplements. A re-evaluation of the need for and dosage schedules of fluoride supplements is warranted.     

Fluoride ingestion from toothpaste and diet in 1- to 3-year-old Brazilian children

OBJECTIVE: This study estimated the total daily fluoride intake of 1- to 3-year-old children from diet and dentifrice. The constituents of the diet were divided into solids, water, milk, and other beverages, which were analyzed separately. The correlation between fingernail fluoride concentrations and the total daily fluoride intake by children was also investigated. METHODS: Thirty-three children, living in a fluoridated area, participated in the study. Fluoride intake from diet was monitored by the 'duplicate plate' method, investigating the different constituents of the diet. Fluoride ingested from dentifrice was determined by subtracting the amount of fluoride recovered after brushing from the amount originally placed onto the child's toothbrush. Fingernails were clipped and collected on three occasions. Fluoride was analyzed with the ion-specific electrode, after hexamethyldisiloxane-facilitated diffusion. Data were tested by anova and Tukey's post hoc tests, Student's t-tests and linear regression (P < 0.05). RESULTS: Mean (+/-SD) fluoride intake from diet and dentifrice was 0.025 +/- 0.013 and 0.106 +/- 0.085 mg/kg body weight/day, respectively, totaling 0.130 mg/kg body weight/day. A strong positive correlation (r = 0.971, P < 0.0001) was seen between the amount of dentifrice loaded onto the brush (0.49 +/- 0.30 g) and the amount of fluoride ingested during each tooth brushing (0.59 +/- 0.45 mg). Among the constituents of the diet, water and milk had a significantly higher contribution to the fluoride intake (0.18 +/- 0.11 mg/day, P < 0.0001), when compared with solids (0.07 +/- 0.05 mg/day) and other beverages (0.07 +/- 0.04 mg/day). Mean (+/-SD) fingernail fluoride concentration on the three dates of collection was 3.11 +/- 1.14, 2.22 +/- 1.47 and 3.53 +/- 1.40 mug F/g. There was no significant correlation between fingernail fluoride concentration and the total fluoride intake. CONCLUSIONS: Most of the children are exposed to a daily fluoride intake above the suggested threshold for dental fluorosis. The dentifrice alone is responsible for an average of 81.5% of the daily fluoride intake, while among the constituents of the diet, water and milk are the most important contributors. In addition, small variations in daily fluoride intake cannot be detected in fingernails.     

Fluorosis and caries prevalence in a community drinking above-optimal fluoridated water

Fluorosis levels and caries prevalence were evaluated in 182 adolescents aged 15-16 yr residing from birth in an area with 5 ppm fluoride in the drinking water. The mean number of surfaces affected by caries in the total study population was 5.46 DMFS. The teeth most susceptible to caries were the first molars. The prevalence of fluorosis was 100% with 53 subjects demonstrating mild fluorosis (according to Dean's index), 83 demonstrating moderate fluorosis, and severe fluorosis diagnosed in 46 subjects. A statistically significant positive association was found between caries prevalence and fluorosis; the more caries experienced, the more severe the fluorosis level. Boys experienced significantly higher fluorosis levels than girls. Further research will investigate the possible variables which may explain this difference in fluorosis by sex.     

Fluoride exposure and dental fluorosis in Newburgh and Kingston, New York: policy implications

OBJECTIVES: This analysis was conducted to determine the changes in the effect of exposure to fluoridation and other sources of fluoride on dental fluorosis in children attending Newburgh and Kingston school districts in New York State. METHODS: Data for this analysis were obtained from two surveys conducted in the 1986 and 1995 school years. Analyses were limited to 3500, 7-14-year-old lifelong residents of a fluoridated or a nonfluoridated community. Dean's classification and DMFS index were used for recording dental fluorosis and caries, respectively. A questionnaire was used to collect fluoride exposure data. Regression procedures were used to estimate the effect of fluoridation, fluoride supplements, and brushing before the age of 2 years on dental fluorosis. RESULTS: Children examined in 1996 were at higher risk for both questionable and very mild to severe dental fluorosis if they received fluoride from water or daily tablet use, or started brushing before the age of 2 years. The increase in risk from 1986 to 1995 was greater for African-American children. CONCLUSION: This analysis showed that the risk of developing dental fluorosis did not decline over time in these communities. Continuous exposure to water fluoridation had an observable effect on dental fluorosis. However, implementation of fluoridation in Newburgh Town did not result in an increase in dental fluorosis prevalence.     

Effect of fluoridated salt intake in infancy: a blind caries and fluorosis study in 8th grade Hungarian pupils

Salt fluoridation is effective at inhibiting caries, but fluorosis prevalence data are deficient. OBJECTIVES: The purpose was to undertake a blind study of caries and tooth mottling in 8th grade school pupils from south-east Hungary who had resided (test) or not resided (control), until November 1985, in a 350 ppm F-/kg domestic salt-fluoridated area during their early years of life. METHODS: In Szeged, blind clinical caries and anterior tooth mottling scoring (+10% repeats) of 49 previously salt-fluoridated (mean age 14.14 years) and 59 non-salt-fluoridated subjects (mean age 14.08 years) were undertaken by one examiner, in June 1997. In addition, radiographic and photographic recordings were taken. In Glasgow, four dental and two lay staff scored the projected 35 mm colour transparencies (+10% repeats) of each pupil's six upper anterior teeth, for tooth mottling. All clinical, radiographic and photographic data were then analysed. RESULTS: Mean DMFS scores were 9.18 (SD=10.72) for test users and 4.51 (SD=6.24) for control users (P<0.01) and, based on repeat observations, clinical reliability=0.99; X-ray reliability=0.95. Clinically, three test children had fluorosis of 10 teeth, with eight teeth in two controls. Photographic scoring by the clinical examiner gave a 97.2% clinical match, while photographic agreements for all four dentist pairs were 92.5%-97.2%, with lay observers' agreements at 89.8%. For both groups, 10% repeats produced 98.5% agreements. In a sole test case "fluorosis" photographic unanimity was obtained, and non-unanimous "possible fluorosis" was recorded by two to four panel members for only three other test and two control subjects. CONCLUSIONS: No evidence was found that significant anterior tooth fluorosis resulted in subjects exposed previously to 350 ppm F-/kg domestic salt from birth to 2.3-4.8 years of age. However, no caries benefit was demonstrated after the 11.5-year salt fluoridation gap. Caries differences seemed social class-related, city-based controls having less disease than rural test subjects, in spite of an identical F- tablet regimen in all schools from 1987, until subjects were 10 years old. These data emphasise (a) the superiority of sustained community-delivered fluoridation and (b) the need to maintain constant fluoride delivery to tooth surfaces, certainly well beyond 10 years of age.     

Dental Fluorosis and Caries Prevalence in Children Residing in Communities with Different Levels of Fluoride in the Water

Objectives: This study investigated the prevalence of dental fluorosis and caries in 7–14-year-old children residing in communities with negligible (NF: 0.2 ppm), optimal (OPF: 1.0 ppm), and four-times optimal (4X OPF: 4.0 ppm) naturally occurring fluoride in their water systems. Methods : Examinations were performed on 344 children who were lifetime residents of their communities. Results : Whether using the tooth surface index of fluorosis or Dean's index, children examined in the 4X OPF community had the highest prevalence of dental fluorosis. While the severity of fluorosis seen in the OPF and NF communities was mild in appearance, the results indicate that fluorosis does occur in optimally and negligibly fluoridated communities. Compared to the NF community, DMFT and DMFS scores in the OPF community were 9.2 percent and 21.2 percent lower, respectively. Conclusions : The ingestion of water containing 1 ppm or less fluoride during the time of tooth development may result in dental fluorosis, albeit in its milder forms. However, in these times of numerous products containing fluoride being available, children ingesting water containing 1 ppm fluoride continue to derive caries protection compared to children ingesting water with negligible amounts of fluoride. Thus, the potential for developing a relatively minor unesthetic condition must be weighed against the potential for reducing dental disease.