Infants' fluoride ingestion from water, supplements and dentifrice

Associations between longitudinal fluoride intakes from birth to age 23 and multi-row detector computed tomography bone densitometry outcomes at age 23

OBJECTIVES

To assess the relationships between longitudinal fluoride intakes and bone densitometry outcomes in young adults.

METHODS

Data were analyzed from the Iowa Fluoride Study and Iowa Bone Development Study, which followed 1,882 infants from birth in 1992. Daily fluoride intakes were assessed using detailed questionnaires sent every 1.5-6 months, and multi-row detector computed tomography (MDCT) scans of distal tibia were obtained from 330 participants aged 23 years. Sex-specific bivariate and multivariable associations with MDCT outcomes were examined using linear regression. Because of the multiple statistical analyses being conducted, p-values < 0.01 were considered statistically significant.

RESULTS

In fully adjusted analyses, no statistically significant (p < 0.01) or suggestive (0.01 < p < 0.05) associations were found between period-specific or cumulative fluoride intake and bone measures for either sex, although there were suggestive positive relationships in unadjusted analyses.

CONCLUSIONS

Longitudinal fluoride intakes had little association with bone measures at age 23. As there were no adverse effects from fluoride intake on bone health in young adults, results support the continued use of fluorides, particularly community water fluoridation is the most cost-effective method of dental caries prevention.

Prevalence and risk factors of dental fluorosis among children aged 8-12 years in Shandong province of China

This study was to investigate the prevalence and severity of children's dental fluorosis (DF) in Shandong and identified the potential risk factors for DF. A total of 87 villages in Shandong were investigated to calculate the prevalence of DF and Community Fluorosis Index (CFI) in 2018-2019. Six hundred and seventy children were enrolled to identify the potential risk factors using univariate and multivariate logistic regressions. Goodman-Kruskal Gamma was used to explore the factors related to the severity of DF. In 87 villages, 1249 of 8700 (14.36%) children still have DF. The prevalence of DF in most villages was below 40% in 2018-2019. Water fluorine concentration when selected for the study and urinary fluorine concentration were related to the risk of DF (P < 0.001). Some eating habits, like lower frequency of eating fresh vegetables, eggs, and beans, were associated with the risk of DF (P < 0.001). The high water fluorine concentration, and lower frequency of eating fresh vegetables, eggs, and beans were also related to the severity of DF (P < 0.001). DF in children in Shandong province is still a common endemic disease. This study tries to provide a useful guide for the prevention and control of DF.

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.

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.

Estimation of daily fluoride intake of infants using the microdiffusion method

BACKGROUND/PURPOSE

The standard of daily fluoride intake (DFI) has been discussed mainly for adults since 1950s in Japan. Although dietary habits have changed significantly in recent years, there have been no further studies on DFI in the past 10 years, and the need for further review has been discussed. Additionally, fluoride bioavailability in infants is higher than that in adults; hence, an excess fluoride intake often manifests symptoms. However, the number of studies on the DFI of infants is less than that of adults. The purpose of this study is to investigate the DFI for Japanese infants to provide adequate fluoride application.

MATERIALS AND METHODS

20 products of infant foods for 4 age groups, 5 products of infant formulas, and 5 products of bottle water available in retail stores in Japan were prepared for this study. Fluoride concentration of each product was measured by microdiffusion method and fluoride ion-selective electrode, and then DFI in infants aged 5, 7, 9, and 12 months were calculated.

RESULTS

According to our study, the DFI in infants aged 5, 7, 9, and 12 months is 185.34 μg/day, 181.16 μg/day, 174.59 μg/day, and 179.19 μg/day, respectively.

CONCLUSION

From this result, it is estimated that the DFI from infant food and beverages in Japan is lower than the standard in other countries. Lifestyles and dietary habits are different in each country, and a new standard of DFI for Japanese children is required to meet the adequate fluoride recommendation.

High Concentration of Fluoride Can Be Increased Risk of Abortion

The presence of fluoride in drinking water can be either beneficial or harmful for human health, depending on its concentration. Most adverse effects of fluoride are observed at high concentrations (above 1.5 mg/L). This study was aimed to evaluate the effect of fluoride concentrations in drinking water on spontaneous abortion in two regions: one with low fluoride concentration and another with high fluoride concentration. The results showed that there is a relationship between the concentration of fluoride in drinking water and abortion, so that the risk of abortion increased at high concentrations of fluoride. However, further studies are needed to clarify this relationship due to the small area and population in this study.

Open Up and Let Us In: An Interprofessional Approach to Oral Health

Dental caries is the single most common chronic disease of childhood in the United States. Access to dental care is one of the barriers to improved oral health for children. Primary care providers who routinely treat children have an established role in prevention and early identification of health problems; thus, they are ideal front-line providers who can detect oral health discrepancies and begin the process of care and prevention.

Comparative Evaluation of Remineralizing Potential of Three Pediatric Dentifrices

Introduction

Dentifrices are available in different formulations and more commonly a single dentifrice is used by whole family; be it an adult or child. However, concerns over high fluoride in pediatric formulations coupled with inability of the children to spit have led to recommendations to minimize fluoride ingestion during toothbrushing by using a small amount of toothpaste by children and incorporating minimal quantity of fluoride in the toothpastes. Literature is scarce on the remineralization potential of popularly known Indian pediatric dentifrices; hence, pediatric dentifrices containing lesser concentration of fluoride have been marketed relatively recently for the benefit of children without posing a threat of chronic fluoride toxicity at the same time.

Aim and objectives

The present study was undertaken to evaluate and compare the remineralization potential of three commercially available Indian pediatric dentifrices with different compositions on artificially induced carious lesions in vitro through scanning electron microscopy (SEM).

Materials and methods

The present in vitro study was conducted on 45 sound extracted primary molar surfaces divided into three groups (15 each). Artificial demineralization was carried out, followed by remineralization using dentifrice slurry as per the group allocation. All the samples were studied for remineralization using SEM and the results statistically compared.

Results

All three dentifrices tested showed remineralization; although insignificantly different from each other but significantly higher compared to the demineralizing surface.

Conclusion

One can use pediatric dentifrices for preventing dental caries and decelerating lesion progression with an added advantage of lower fluoride toxicity risk.

How to cite this article

Kapoor A, Indushekar KR, Saraf BG, Sheoran N, Sardana D. Comparative Evaluation of Remineralizing Potential of Three Pediatric Dentifrices. Int J Clin Pediatr Dent 2016;9(3):186-191.

Water fluoridation: a critical review of the physiological effects of ingested fluoride as a public health intervention

Fluorine is the world's 13th most abundant element and constitutes 0.08% of the Earth crust. It has the highest electronegativity of all elements. Fluoride is widely distributed in the environment, occurring in the air, soils, rocks, and water. Although fluoride is used industrially in a fluorine compound, the manufacture of ceramics, pesticides, aerosol propellants, refrigerants, glassware, and Teflon cookware, it is a generally unwanted byproduct of aluminium, fertilizer, and iron ore manufacture. The medicinal use of fluorides for the prevention of dental caries began in January 1945 when community water supplies in Grand Rapids, United States, were fluoridated to a level of 1 ppm as a dental caries prevention measure. However, water fluoridation remains a controversial public health measure. This paper reviews the human health effects of fluoride. The authors conclude that available evidence suggests that fluoride has a potential to cause major adverse human health problems, while having only a modest dental caries prevention effect. As part of efforts to reduce hazardous fluoride ingestion, the practice of artificial water fluoridation should be reconsidered globally, while industrial safety measures need to be tightened in order to reduce unethical discharge of fluoride compounds into the environment. Public health approaches for global dental caries reduction that do not involve systemic ingestion of fluoride are urgently needed.

Fluoride Exposure, Caregiver Education, and Decayed, Missing, Filled Teeth (dmft) in 2-5 year-old English or Spanish Speaking Children

Dental caries is a multifactorial disease that includes behavioral and cultural components. The study’s purpose was to determine the caries experienced (as measured by dmft) in a group of 2-5 y/o children, assess their family and home environment including consumption of fluoridated drinking water, use of a fluoride containing dentifrice, and level of caregiver formal education.

Parents of children referred for dental treatment under general anesthesia and who either spoke and read English or Spanish were recruited and consent obtained. Selected information on the family home, parental education and selected fluoride contact data was obtained. An oral clinical examination of the child assisted by intraoral radiographs was completed and the number of decayed, missing, filled primary teeth (dmft) recorded for each child. Bitewings were obtained if posterior or anterior teeth contacts were closed but only periapical radiographs were obtained if contacts were open. Children of English speaking caregivers had statistically more dmft after controlling for the effect of the child’s age and years of parental education (p=0.04). English speaking families had lived in their current home longer and the parent had more formal education than did the Spanish speaking parent. When available, the English children drank municipal tap water more often than did the Spanish children. Spanish speaking parents often chose bottled drinking water. No difference between the two groups was found in the use of tap water for cooking or the use of fluoridated dentifrice.

In conclusion, increased parent education, language spoken by the parents and time living in the current home were not associated with lower dmft. Drinking fluoridated drinking water did not affect the dmft. However, using fluoridated water when available to cook and using fluoride containing dentifrice by both groups may have been mutually beneficial.

Fluoride intake from fluids and urinary fluoride excretion by young children in Kuwait: a non-fluoridated community

OBJECTIVES

To determine the pattern of fluid consumption, fluoride intake from the fluids and urinary fluoride excretion by children aged 1-9 years in Kuwait, a nonfluoridated community.

METHODS

Using the cluster sampling technique, children aged 1-9 years were chosen from 2000 randomly selected households in Kuwait. Questionnaires were then administered to their mothers to determine the children's daily fluid intake. Fluoride concentrations in tap water as well as all brands of bottled water and beverages consumed by the children were measured, using the fluoride ion-specific electrode. Fluoride excretion was determined in 400 randomly selected children, based on fluoride/creatinine ratio.

RESULTS

The mean daily fluid consumption by the children was high, being 1115-1545 ml. About 40% of the fluid intake was plain (tap and bottled) water and approximately 10% of the children drank bottled water exclusively. Fluoride concentration in tap water was low (0.04±SD 0.02 ppm), but was higher in bottled water (0.28±SD 0.40 ppm). Mean daily fluoride ingestion from fluids was 0.013-0.018 mg/kg body weight (bw). Even after allowing for fluoride ingestion from other sources, mean daily fluoride ingestion was still below 0.1 mg/kg bw set by the United States of America Institute of Medicine as the lowest-observed-adverse-effect level for moderate enamel fluorosis in children aged up to 8 years. Furthermore, the mean daily urinary fluoride excretion of 128-220 μg was below the provisional standard of 360-480 μg for optimal fluoride usage by children aged 3-5 years.

CONCLUSION

Fluoride ingestion from fluids and urinary fluoride excretion by the children were below the recommendations for optimal fluoride usage. Thus, there is room for an upward adjustment of fluoride level in public drinking water supplies in Kuwait, as a caries preventive measure.

Effects of different amounts of a low fluoride toothpaste on primary enamel lesion progression: a preliminary study using in vitro pH-cycling system

AIMS

To evaluate and compare the efficacy of pea and half-pea portions of child formula fluoride (500 ppm) toothpaste on artificially created enamel lesions in primary teeth.

METHODS

Sound primary incisors were painted with nail varnish, leaving a 1 mm wide window and then placed in a demineralising solution for 96 h to produce artificial carious lesions 60-100 microm deep. The teeth were longitudinally sectioned (100 microm thick) and divided into 3 groups. Group A: treated with a pea-sized portion of a non-fluoride containing toothpaste (1:3, toothpaste: deionized water), while Groups B and C were treated with half-pea-sized and pea-sized portions of a 500 ppm fluoride containing toothpaste, respectively. The pH-cycling model was utilized for 7 days.

RESULTS

Groups A and B lesions increased in depth by 60% while those in Group C increased by 19%. The mineral content of the surface zone decreased significantly in Groups A and B but not in Group C.

CONCLUSION

Reduction of the amount of fluoride toothpaste to less than a pea-size in order to minimize the risk of fluorosis should be undertaken with caution because it may compromise the cariostatic effects of the toothpaste.

Comparison of the remineralizing potential of child formula dentifrices

BACKGROUND

Although child formula fluoridated dentifrices can be used safely by young children their remineralizing capability remains questionable.

AIMS

To evaluate the remineralizing potential of child formula dentifrices on primary teeth.

DESIGN

In vitro single-section technique utilizing a 7 days pH-cycling model.

METHODS

Primary teeth were placed in demineralizing solution for 96 h to produce artificial carious lesions 100 μm deep, and then cut longitudinally into 50 sections 100-150 μm thick and randomly assigned to five groups. Sections in Groups A to D were treated with dentifrices containing 500 ppm AmF, 500 ppm MFP, 500 ppm MFP and xylitol, or 500 ppm NaF, respectively. Group E sections were treated with a nonfluoridated dentifrice.

OUTCOME MEASUREMENTS

Lesions were evaluated using polarized light microscopy and microradiography.

RESULTS

Group D (500 ppm NaF) sections exhibited a significant decrease in lesion depth, whereas those in Group E (nonF) showed a significant increase in depth (P<0.05, paired t-test). Decrease in lesion progression was observed in Groups A, B and C.

CONCLUSIONS

The 500 ppm NaF dentifrice demonstrated remineralization of carious lesions by virtue of a significant decrease in lesion depth; whereas dentifrices that contained AmF, MFP and MFP with xylitol decelerated the progression of demineralization.

Assessment of water contribution on total fluoride intake of various age groups of people in fluoride endemic and non-endemic areas of Dindigul District, Tamil Nadu, South India

The prevalence of fluorosis is mainly due to the intake of large quantities of fluoride through water. It is necessary to determine the contribution of water used for drinking and food processing and other diet sources on daily fluoride intake for finding the ways to reduce the excess fluoride intake than the minimum safe level intake of 0.05 mg/kg/day. The main objectives of this study are to determine the quantitative impact of water through drinking and cooking of food and beverages on total fluoride intake as well as to estimate the contribution of commonly consumed diet sources on total fluoride intake. Contribution of water on daily fluoride intake and estimation of total fluoride intake through the diet sources were accomplished through analysis of fluoride in drinking water, solid and liquid food items, Infant formulae, tea and coffee infusions using fluoride ion selective electrode. Determination of incidence of fluorosis in different fluoride endemic areas in Dindigul District of Tamil Nadu, South India is achieved through clinical survey. The percentage of daily fluoride intake through water is significantly higher for infants than children, adults and old age groups of people. The percentile scores of fluoride intake through water from drinking and cooking increases with increase of water fluoride level. The rate of prevalence of fluorosis is higher in adolescent girls and females than adolescent boys and males residing in high fluoride endemic areas. More than 60% of the total fluoride intake per day derived from water used for drinking and food processing. Hence the people residing in the fluoride endemic areas in Dindigul District of Tamil Nadu, South India are advised to take serious concern about the fluoride level of water used for drinking and cooking to avoid further fluorosis risks.

Epidemiology of fluorosis and dental caries according to different types of water supplies

The aim of this article is to investigate the relationship between fluorosis/dental caries in schools, according to the level of fluoride in public water supply. The sample comprised of twelve-year-old daytime students (360) of both genders, attending schools close to the region where they were born. The schools were classified into three groups according to the presence of fluoride in the water supply: 1) fluoridation in the Water Treatment Station-WTS; 2) Direct Fluoridation in Wells-DFW; and 3) Non Fluoridated Areas-NFA. The chi2 and Goodman tests (significance=5%) were used to evaluate the association between the origin of water and degree of fluorosis; percentage of distribution and descriptive measures were used for investigation of the degree of fluorosis. The following outcomes were predominant: presence of dental caries in the entire sample (P<0.05); absence of fluorosis in both genders, for white individuals and subjects living in areas supplied by both DFW and NFA (P<0.05). There was no difference in the severity of fluorosis between the sources of water supply (P>0.05). Dental caries is still an important problem in this population, despite the establishment of preventive measured. The observation of fluorosis in students living in non-fluoridated areas confirms the presence of other sources of fluoride.

Associations between fluorosis of permanent incisors and fluoride intake from infant formula, other dietary sources and dentifrice during early childhood

OBJECTIVES

The authors describe associations between dental fluorosis and fluoride intakes, with an emphasis on intake from fluoride in infant formula.

METHODS

The authors administered periodic questionnaires to parents to assess children's early fluoride intake sources from beverages, selected foods, dentifrice and supplements. They later assessed relationships between fluorosis of the permanent maxillary incisors and fluoride intake from beverages and other sources, both for individual time points and cumulatively using area-under-the-curve (AUC) estimates. The authors determined effects associated with fluoride in reconstituted powdered infant formulas, along with risks associated with intake of fluoride from dentifrice and other sources.

RESULTS

Considering only fluoride intake from ages 3 to 9 months, the authors found that participants with fluorosis (97 percent of which was mild) had significantly greater cumulative fluoride intake (AUC) from reconstituted powdered infant formula and other beverages with added water than did those without fluorosis. Considering only intake from ages 16 to 36 months, participants with fluorosis had significantly higher fluoride intake from water by itself and dentifrice than did those without fluorosis. In a model combining both the 3- to 9-months and 16- to 36-months age groups, the significant variables were fluoride intake from reconstituted powder concentrate formula (by participants at ages 3-9 months), other beverages with added water (also by participants at ages 3-9 months) and dentifrice (by participants at ages 16-36 months).

CONCLUSIONS

Greater fluoride intakes from reconstituted powdered formulas (when participants were aged 3-9 months) and other water-added beverages (when participants were aged 3-9 months) increased fluorosis risk, as did higher dentifrice intake by participants when aged 16 to 36 months.

CLINICAL IMPLICATIONS

Results suggest that prevalence of mild dental fluorosis could be reduced by avoiding ingestion of large quantities of fluoride from reconstituted powdered concentrate infant formula and fluoridated dentifrice.

Considerations on optimal fluoride intake using dental fluorosis and dental caries outcomes--a longitudinal study

OBJECTIVES

The "optimal" intake of fluoride has been widely accepted for decades as between 0.05 and 0.07 mg fluoride per kilogram of body weight (mg F/kg bw) but is based on limited scientific evidence. The purpose of this paper is to present longitudinal fluoride intake data for children free of dental fluorosis in the early-erupting permanent dentition and free of dental caries in both the primary and early-erupting permanent teeth as an estimate of optimal fluoride intake.

METHODS

Data on fluoride ingestion were obtained from parents of 602 Iowa Fluoride Study children through periodic questionnaires at the ages of 6 weeks; 3, 6, 9, 12, 16, 20, 24, 28, 32, and 36 months; and then at 6-month intervals thereafter. Estimates of total fluoride intake at each time point were made by summing amounts from water, dentifrice, and supplements, as well as other foods and beverages made with, or containing, water. Caries data were obtained from examinations of children at ages 5 and 9 years, whereas fluorosis data were obtained from examinations of children only at age 9 years.

RESULTS

The estimated mean daily fluoride intake for those children with no caries history and no fluorosis at age 9 years was at, or below, 0.05 mg F/kg bw for nearly all time points through the first 48 months of life, and this level declined thereafter. Children with caries had generally slightly less intakes, whereas those with fluorosis generally had slightly higher intakes.

CONCLUSIONS

Given the overlap among caries/fluorosis groups in mean fluoride intake and extreme variability in individual fluoride intakes, firmly recommending an "optimal" fluoride intake is problematic.

Preventive oral health intervention for pediatricians

This policy is a compilation of current concepts and scientific evidence required to understand and implement practice-based preventive oral health programs designed to improve oral health outcomes for all children and especially children at significant risk of dental decay. In addition, it reviews cariology and caries risk assessment and defines, through available evidence, appropriate recommendations for preventive oral health intervention by primary care pediatric practitioners.

Analysis of fluoride concentration in mother's milk substitutes

The aim of the present study was to determine the fluoride concentration in some brands of mother's milk substitutes and evaluate the possibility of developing dental fluorosis by consuming these products. The products, all powdered, were divided into 3 groups: infant formulae (group I, n = 7), milk-based (group M, n = 8) and soy-based (group S, n = 3). Samples from 3 cans of different batches of each brand were reconstituted in deionized water and analyzed using the specific electrode method, after hexamethyldisiloxane (HMDS) facilitated diffusion. The fluoride content (mg F/L) of the products ranged from 0.044 to 0.326 (I), 0.014 to 0.045 (M) and 0.253 to 0.702 (S). There was significant difference in the fluoride content of cans from distinct batches (p < 0.05) in most of the brands. The reconstitution of all products in water with optimal fluoride concentration for consumption during the mineralization phase of the primary teeth could result in daily fluoride intake above 0.07 mg F/kg body weight/day. Therefore, the consumption of these products, especially when reconstituted with optimally fluoridated water, could increase the risk of developing dental fluorosis.

Total fluoride intake in children aged 22-35 months in four Colombian cities

OBJECTIVE

To obtain information on the level of total fluoride intake from food, beverages and toothpaste by children at the age of 22-25 months of low and high socioeconomic status (SES) in major Colombian cities.

METHODS

Daily fluoride intake was assessed by the duplicate plate method and by recovered toothpaste solution during a 3-day period and afterwards analysed by the microdiffusion method.

RESULTS

Mean daily fluoride intake was 0.11 (+/-0.10), 0.14 (+/-0.12), 0.10 (+/-0.07) and 0.07 (+/-0.06) mg/kg body weight (bw)/day in Bogota, Medellin, Manizales and Cartagena, respectively. The total fluoride intake was higher in low-SES subjects in the cities of Medellin and Bogota. In the high-SES children of the four cities, the average intakes ranged from 0.06 to 0.09 mg F/kg bw, whereas, the low-SES children in three cities had intakes between 0.11 and 0.21 mg F/kg bw (Cartagena, 0.07). Toothpaste (containing 1000-1500 ppm F, with 1500 ppm F being more common) accounted for approximately 70% of total fluoride intake, followed by food (24%) and beverages (<6%). More than half the children had their teeth brushed by an adult, on average twice a day, using 0.22-0.65 g of toothpaste.

CONCLUSION

Children from three Colombian cities have a mean total daily fluoride intake above the 'optimal range'. Health authorities should promote an appropriate use of fluoridated dentifrices discouraging the use of dentifrices containing 1500 ppm F in children younger than 6 years of age and promoting a campaign of education of parents and oral health professionals on adequate toothbrushing practices.

Associations between Intakes of Fluoride from Beverages during Infancy and Dental Fluorosis of Primary Teeth

OBJECTIVE

We describe associations between primary tooth fluorosis status and intakes of beverages and fluoride from these beverages during infancy.

METHODS

Subjects (n = 677) are members of the Iowa Fluoride Study, a cohort of young children followed from birth. Food and nutrient intakes were obtained from 3-day diet records. Diets were analyzed at 6 weeks, 3, 6, 9, 12 and 16 months and cumulatively for 6 weeks through 16 months of age. Primary tooth fluorosis was assessed at 4.5-6.9 years of age and defined as present or absent. Multiple logistic regression analyses were used to develop models to predict fluorosis status.

RESULTS

Water-based beverage intakes were higher in subjects with fluorosis than in those without. Specifically, higher intakes of water used to reconstitute formulas at 3, 6 and 9 months; any intake of water as a beverage at 16 months; and higher intakes of combined 100% juice and miscellaneous beverages at 16 months were positively associated with fluorosis (p < 0.05). Fluoride intakes from water sources were also higher in subjects with fluorosis than in those without. Specifically, higher intakes of fluoride from water used to reconstitute formulas at 3, 6, 9 and 12 months and for 6 weeks through 16 months, and higher intakes of fluoride from water as a beverage at 16 months and for 6 weeks through 16 months were positively associated with fluorosis (p < 0.05).

CONCLUSION

Infant beverages, particularly infant formulas prepared with fluoridated water, can increase the risk of fluorosis in primary teeth.

Effect of 0.02% NaF solution on enamel demineralization and fluoride uptake by deciduous teeth in vitro

The application of 0.02% NaF solution on teeth with a cotton swab instead of brushing with fluoride dentifrice has been suggested for young children to reduce the risk of dental fluorosis, but its anticariogenic effect has not been evaluated. Thus, we studied the in vitro effect of 0.02% NaF solution on enamel demineralization and fluoride uptake in deciduous teeth; non-fluoride dentifrice and fluoride dentifrice (1,100 mg F/g) were used, respectively, as negative and positive controls. The treatment with fluoride dentifrice was more effective in reducing enamel demineralization (p < 0.05) and on fluoride uptake by the enamel (p < 0.05) than the non-fluoride dentifrice and the 0.02% NaF solution. Data suggest that the alternative use of 0.02% NaF solution instead of fluoride dentifrice should be reevaluated especially if dental caries are to be controlled.

FLUORIDE ANALYSIS OF FOODS FOR INFANTS AND ESTIMATION OF DAILY FLUORIDE INTAKE

The mean daily fluoride intake in infants was estimated on the basis of their intake of commercial foods for infants in Japan and evaluated in order to establish the effectiveness and safety criteria for water fluoridation, which is practiced as a preventive measure for dental caries suitable in life stages from children to the elderly. Based upon the intakes of foods for infants, the mean daily fluoride intake was estimated to be 0.166 mg in infants aged 3-4 months, 0.202 mg in those aged 5-6 months, and 0.266 mg in those aged 7-8 months. The mean daily fluoride intake per kg of body weight at these ages was in the range of 0.023-0.029 mg/kg, which was about half of the standard daily fluoride intake for infants and children advocated by Ophaug et al., as 0.05-0.07 mg/kg. From our results, the daily fluoride intake of infants from foods in Japan is estimated to be equivalent to or lower than the values of previous reports in non-fluoridated areas. Consequently, our data support the argument that water fluoridation and the appropriate use of fluoride for dental caries prevention in Japan are needed on the basis of scientific criteria in terms of fluoride exposure related to food intake during tooth formation.

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.

Water consumption and nursing characteristics of infants by race and ethnicity

OBJECTIVES

The purpose of this project was to determine racial/ethnic differences in water consumption levels and nursing habits of children younger than 2 years old.

METHODS

Data from the 1994-96 Continuing Survey of Food intakes by individuals (CSFII) were used for these analyses. Water consumption and breast-feeding data on 946 children younger than 2 years old were used.

RESULTS

For black non-Hispanic children younger than 2 years old (n = 121), 5.3 percent of the children were currently being breast fed. This percentage was less than that seen in other racial/ethnic groups. For white non-Hispanic children (n = 620), this percentage was 10.8 percent; for Hispanic children (n = 146), 12.2 percent; for "other" children, 18.5 percent (n = 59). Black non-Hispanic children had the highest total water consumption (128.6 ml/kg/day) among all groups, white non-Hispanic had the lowest (113.2 ml/kg/day). These differences were not statistically significant in multivariate regression modeling. Black non-Hispanic children also drank more tap water (21.3 ml/kg/day) than white non-Hispanic children (12.7 ml/kg/day) and Hispanic children (14.9 ml/kg/day). The difference was statistically significant in multivariate regression modeling.

CONCLUSIONS

The differences in breast feeding and water consumption observed among black children younger than 2 years of age could be a factor in the observed higher levels of fluorosis in black children compared to other children.

Decision to Fluoridate. 2. Intake of Fluoride from Nonmilk Fluids by Children under two Years of Age in Lebanon

This study investigated fluoride intake from fluids consumed by children 0 to 2 years of age residing in urban and rural areas in Lebanon. An area sample of 150 families with children was selected from Beirut and three villages in the Shouf Area in Mount Lebanon (70 and 80 families, respectively). Food diaries for two weekdays and one weekend day were obtained for children aged 0 to 2 years in urban and rural areas (76 and 85 children, respectively), and their fluoride intake from fluids was assessed. Children were given tea, anise, mint, and mixed herbal teas for various reasons, such as their medicinal, warming, and calming effects. They were also given orange flower water, orange juice, and rice water. In urban areas, the fluoride intakes from fluids, expressed as percentages of the estimated safe and adequate (ESA) intake of fluoride, were 48.5% among children 0 to 6 months old, 110.5% among those 7 to 12 months old, 21.9% among those 13 to 18 months old, and 43.5% among those 19 to 24 months old. In rural areas, the ESA fluoride intake from teas was 180.9%, 115.9%, 102.0%, and 71.5% for children aged 0 to 6 months, 7 to 12 months, 13 to 18 months, and 19 to 24 months, respectively. In view of the substantial level of intake of fluoride from nonmilk fluids among children in this study, decisions regarding water fluoridation in Lebanon should consider these results.

Total fluoride intake and implications for dietary fluoride supplementation

This paper reviews the history and validity of recommended "optimal" levels of systemic fluoride intake and the available information on levels of fluoride intake in young children from foods and beverages (including water), dentifrices, dietary fluoride supplements, mouthrinses, and gels. Most of the studies emphasize the substantial variation in ingestion among individuals. Often, a substantial proportion of individuals received fluoride well beyond the mean exposure reported in the study. Limitations in the existing data make it difficult to determine the total distribution of fluoride intake from all sources. Therefore, hypothetical combinations of possible daily fluoride intake from the three main sources (diet, dentifrices, and supplements) are presented for those aged 6, 12, 24, and 36 months, with associated mean intake per kg body weight. Findings suggest that some children exceed the "optimal" level of fluoride intake from single sources alone, while others can from a combination of sources. Moreover, if current recommended "optimal" levels, which have been derived on an empirical basis, are actually lower than what has been quoted in the literature, then more children could be ingesting excessive amounts of fluoride, which could increase their risk of developing objectionable dental fluorosis. The variation and complexity of fluoride ingestion from all sources should be considered in the evaluation of recommendations for use of dietary fluoride supplements.

Fluoride intake from foods, beverages and dentifrice by young children in communities with negligibly and optimally fluoridated water: a pilot study

While the level of fluoride intake that affords optimal cariostatic efficacy without causing dental fluorosis is not precisely known, it has been suggested that the threshold of fluoride exposure above which fluorosis may occur is between 0.05 and 0.07 mg/kg/day.

OBJECTIVE

To monitor and compare fluoride intake from diet and dentifrice use (theoretical F: 0.10-0.11%) by three groups of 16- to 40-month-old children: two groups living in the negligibly water-fluoridated communities of San Juan, Puerto Rico, and Connersville, Indiana, and the third group residing in the optimally water-fluoridated region of Indianapolis, Indiana.

METHODS

Fluoride intake from diet was monitored by the "duplicate plate" method, and fluoride ingested from dentifrice was determined by subtracting the amount of fluoride recovered after brushing from the amount originally placed on the child's toothbrush.

RESULTS

The mean combined amount of fluoride ingested daily by children living in the negligibly fluoridated communities was not significantly different from that ingested by children in the fluoridated community. The major component of fluoride ingested by children in the negligibly fluoridated communities came from fluoridated dentifrice, and in the fluoridated area children ingested as much fluoride from toothpaste as they did from beverages. In San Juan mean daily fluoride intake was within the estimated range for safe fluoride exposure; however, in the "halo" community of Connersville and in Indianapolis, daily fluoride ingested by many of the children may have exceeded this level.

CONCLUSION

Attention needs to be given, in negligibly water-fluoridated as well as in optimally water-fluoridated communities, to reducing the daily intake of fluoride by young children in order to avoid putting them at risk of developing dental fluorosis.

Patterns of dietary fluoride supplement use during infancy

OBJECTIVES

This paper reports on patterns of dietary fluoride supplement use during infancy.

METHODS

Data were collected by mail for a birth cohort (n = 1,072) studied at 6 weeks and 3, 6, 9, and 12 months of age.

RESULTS

Percentages using supplements were 13.7 at 6 weeks, 13.4 at 3 months, 16.5 at 6 months, 13.0 at 9 months, and 12.1 at 12 months. Among those receiving supplements, mean proportions of weeks that supplements were received during the different time periods varied from 0.59 to 0.80. Number of days per week receiving supplements averaged 4.8 to 5.0. Mean fluoride dosages when supplements were received were 0.22 mg to 0.24 mg. Estimated average daily fluoride ingestion per day (among those receiving supplements during that time period and factoring in those days and weeks that supplements were not received) was 0.11 mg at 6 weeks, 0.15 mg at 3 months, 0.12 mg at 6 months, 0.11 mg at 9 months, and 0.14 mg at 12 months. Among the subset of 129 children with complete data at all time points who used supplements sometime during their first year of life, mean annual daily supplement dosage was 0.07 mg fluoride, with 75 percent having less than or equal to 0.10 mg. Those infants with mothers and fathers with more education were more likely to receive supplements.

CONCLUSIONS

Group average use of fluoride supplements was fairly consistent over the 12 months; however, individual patterns varied substantially. Estimated actual mean daily fluoride intake when including days that supplements were not received was substantially less than the recommended 0.25 mg per day.

Nutrition and oral health guidelines for pregnant women, infants, and children

Good oral health care and nutrition during pregnancy, infancy, and childhood are essential but often overlooked factors in the growth and development of the teeth and oral cavity. Pregnant women and parents and caregivers of infants and children often receive little guidance about proper preventive dental and oral health care, including fluoride and dietary measures. Pregnant women can maintain their health through proper diet, good oral hygiene, and appropriate use of fluoride. An adequate diet during gestation is important for optimal oral development of the fetus. To promote good oral health in infancy, caregivers need to provide the infant with appropriate amounts of fluoride in addition to a healthful diet. As the teeth erupt into the mouth, the caregiver needs to clean the teeth thoroughly on a daily basis. When solid foods are introduced in later infancy, it is also important to limit the frequency of caries-promoting fermentable carbohydrates between meals. Good oral hygiene habits and dietary practices that emphasize minimum exposure to retentive, fermentable carbohydrates; use of fluoridated water; and a varied, balanced diet should continue throughout childhood to set the stage for optimal oral health for a lifetime.