Sources of fluoride intake in children

Exploring the Impact of Blood Disorders on Dental Caries

Blood comprises various cellular elements and serves as our immune system's second line of defense. Deviations from its normal composition can have adverse effects on health. At the same time, the oral mucosa in the oral cavity functions as the body's first line of defense, and any anomalies or diseases within it can give rise to both systemic and oral complications. If left untreated, caries can lead to severe tooth damage or extraction, potentially affecting an individual's nutrition and overall health. This review article focuses on the importance of understanding the intricate relationship between blood disorders and oral health. It underscores the profound impact of oral manifestations of blood disorders such as β-thalassemia, sickle cell disease, iron deficiency anemia, leukemia, hemophilia, Plummer-Vinson syndrome, erythroblastosis fetalis, Fanconi anemia, cyclic neutropenia, and acute lymphoblastic leukemia on the overall well-being of an individual.

A comparative evaluation of the fluoride content in commercially available infant formulae in India: An in vitro study

CONTEXT

The most critical period for enamel fluorosis to develop is during the early years of life when enamel formation occurs. To minimize the risk of dental fluorosis development, monitoring fluoride intake during teeth development has been suggested. As infant formulae are major source of nutrition in infants, it is important to determine the fluoride content in them in order to monitor the fluoride intake in infants.

AIMS

To estimate and comparatively evaluate the fluoride content in different commercially available infant formulae in India.

METHODOLOGY

A total of 16 commercially available infant formulae were collected from local pharma/grocery stores, in which 14 were milk based (Group M) and 2 were soy based (Group S). Fluoride content of the formulae was evaluated using ORION F selective electrode.

STATISTICAL ANALYSIS USED

ANOVA test, t-test.

RESULTS

The mean F values for groups M and S were found to be 0.031 and 0.07 ppm, respectively. Fluoride content of milk-based formulae was significantly lesser (P < 0.001) than soy-based formulae. Daily fluoride intake through the tested formulae was in the range of 0.013 mg and 0.105 mg when calculated following the manufacturer's preparation guidelines.

CONCLUSIONS

Infant formulae alone were unlikely to be a risk factor for dental fluorosis, but when reconstituted with optimally fluoridated water, they can be a risk factor for the development of dental fluorosis.

Dietary Fluoride Intake by Children: When to Use a Fluoride Toothpaste?

Fluoride is recommended for its cariostatic effect, but excessive fluoride intake may have health risks. Increased prevalence of dental fluorosis in areas with low fluoride content in drinking water has been attributed to the inappropriate excessive intake of fluoride supplements (tablets and drops) and toothpaste ingestion. The aim of the present study was to estimate the fluoride intake and the risk of fluorosis in children (6 months-6 years) in the Castelli Romani area (province of Rome, Italy), which is volcanic, therefore with a higher concentration of fluorine. Measurements of the fluoride content in drinking water, mineral waters, vegetables and commercial toothpaste for children were performed. The fluoride concentrations of all samples were determined using a Fluoride Ion Selective Electrode (GLP 22, Crison, Esp). Data were analyzed by descriptive statistics. Differences between samples were determined by Student's t-test. The fluoride content in tap water samples collected from public sources averaged from 0.35 to 1.11 ppm. The Pavona area showed the highest content of fluoride with respect to the others (p ≤ 0.05). The fluoride content in mineral water samples averaged from 0.07 to 1.50 ppm. The fluoride content of some vegetables showed increased mean values when compared to control vegetables (p ≤ 0.05). Within the limitations of the present study, considerations should be made when prescribing fluoride toothpaste for infants (6 months-4 years) in the areas with high fluoride content, because involuntary ingestion is consistent.

Exogenous Intake of Fluorides in Caries Prevention: Benefits and Risks

Caries incidence and prevalence have decreased significantly over the last few decades due to widespread use of fluoride. However, an increase in the prevalence of dental fluorosis has been reported in both fluoridated and non-fluoridated communities. Care must be taken to ensure that a balance between the optimal fluoride preventive effect at the individual and community level and minimal risk of dental fluorosis is maintained. This review describes the main sources of fluoride intake that have been identified: fluoridated drinking water, dietary fluoride supplement, and topical forms comprising toothpastes, rinses, gels and varnishes. The cited data were taken from meta-analytic studies and reports from Cochrane database systematic reviews up to December 2019. Efficiency, but safety, of topically applied fluorides in individual home care is dependent on the degree of compliance of individuals/parents and on the level of competence of providers of preventive counselling. The broad spectrum of these resources allows individualization of fluoride prevention based on risk analysis of caries attack and taking into consideration other preventive measures.

Guidelines on the use of fluoride for caries prevention in children: an updated EAPD policy document

AIM

To update the exisitng European Academy of Paediatric Dentistry (EAPD) 2009 fluoride guidelines.

METHODS

Experts met in Athens, Greece duirng November 2018 for the following groups: I Fluoride toothpastes, II Fluoride gels, rinses and varnishes, III Fluoridated milk, fluoridated salt, tablets/lozenges and drops, IV Water fluoridation. Systematic reviews and meta-analyses were reviewed and discussed for each of the groups. The GRADE system was used to assess the quality of evidence which was judged as HIGH, MODERATE, LOW or VERY LOW based on the assessment of eight criteria which can influence the confidence of the results. Following the quality assessment, GRADE was then used to indicate the strength of recommendation for each fluoride agent as STRONG or WEAK/CONDITIONAL.

RESULTS

Parents must be strongly advised to apply an age-related amount of toothpaste and assist/supervise tooth brushing until at least 7 years of age. The EAPD strongly endorses the daily use of fluoride as a major part of any comprehensive programme for the prevention and control of dental caries in children. Regardless of the type of programme, community or individually based, the use of fluoride must be balanced between the estimation of caries-risk and the possible risks of adverse effects of the fluorides. Fluoride use is considered safe when the manufacturer's instructions are followed. Preventive programmes should be re-evaluated at regular intervals and adapted to a patient's or population's needs and risks.

CONCLUSIONS

For the majority of European Countries, the EAPD recommends the appropriate use of fluoride toothpaste in conjunction with good oral hygiene to be the basic fluoride regimen.

Current Guidance for Fluoride Intake: Is It Appropriate?

The purpose of this report is to examine critically the appropriateness of the current guidance for fluoride intake in the population (0.05-0.07 mg F/kg bodyweight/d), consider whether changes to the current guidance are desirable, and suggest further research that will strengthen the evidence base for future decisions on guidance/advice in this area. The benefits and the risks of using fluoride particularly concern preschool children because it is at this age that excessive fluoride intake may result in dental fluorosis. Data from mostly cross-sectional studies show a wide variation in exposure and a considerable variation in the amount of fluoride ingested. Fluorosis, mostly mild, is commonly observed. For considering changes in current guidance, there is a need for more knowledge on the relationship between exposure to fluoride at an early age and the development of fluorosis. For that, prospective epidemiological studies with sufficiently large and representative samples of children are required. It is also important to study children in communities both with and without water fluoridation and to include populations where salt or milk fluoridation is used. There is also a need for professional agreement on acceptable levels of mild and moderate/severe fluorosis and a more comprehensive knowledge on the appreciation of mild fluorosis among the public.

Role of fluoride induced epigenetic alterations in the development of skeletal fluorosis

Fluoride is an essential trace element required for proper bone and tooth development. Systemic high exposure to fluoride through environmental exposure (drinking water and food) may result in toxicity causing a disorder called fluorosis. In the present study, we investigated the alteration in DNA methylation profile with chronic exposure (30 days) to fluoride (8 mg/l) and its relevance in the development of fluorosis. Whole genome bisulfite sequencing (WGBS) was carried out in human osteosarcoma cells (HOS) exposed to fluoride. Whole genome bisulfite sequencing (WGBS) and functional annotation of differentially methylated genes indicate alterations in methylation status of genes involved in biological processes associated with bone development pathways. Combined analysis of promoter DNA hyper methylation, STRING: functional protein association networks and gene expression analysis revealed epigenetic alterations in BMP1, METAP2, MMP11 and BACH1 genes, which plays a role in the extracellular matrix disassembly, collagen catabolic/organization process, skeletal morphogenesis/development, ossification and osteoblast development. The present study shows that fluoride causes promoter DNA hypermethylation in BMP1, METAP2, MMP11 and BACH1 genes with subsequent down-regulation in their expression level (RNA level). The results implies that fluoride induced DNA hypermethylation of these genes may hamper extracellular matrix deposition, cartilage formation, angiogenesis, vascular system development and porosity of bone, thus promote skeletal fluorosis.

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.

Effects of titanium dioxide nanoparticles derived from consumer products on the marine diatom Thalassiosira pseudonana

Increased manufacture of TiO₂ nanoproducts has caused concern about the potential toxicity of these products to the environment and in public health. Identification and confirmation of the presence of TiO₂ nanoparticles derived from consumer products as opposed to industrial TiO₂ NPs warrant examination in exploring the significance of their release and resultant impacts on the environment. To this end, we examined the significance of the release of these particles and their toxic effect on the marine diatom algae Thalassiosira pseudonana. Our results indicate that nano-TiO₂ sunscreen and toothpaste exhibit more toxicity in comparison to industrial TiO₂ and inhibited the growth of the marine diatom T. pseudonana. This inhibition was proportional to the exposure time and concentrations of nano-TiO₂. Our findings indicate a significant effect, and therefore, further research is warranted in evaluation and assessment of the toxicity of modified nano-TiO₂ derived from consumer products and their physicochemical properties.

Fluoride levels in UK infant milks

AIM

To provide a comprehensive report of fluoride concentration in UK infant milks and estimate their contribution to daily fluoride intake.

METHODS

A total of 60 formula milk products available commercially or within a hospital environment were analysed, along with eight pasteurised cow's milk samples. Formula milk products requiring preparation were reconstituted with fresh Leeds tap water (0.02 ppmF). Fluoride concentration was measured for all products directly using an ion selective electrode after addition of low-level total ionic strength adjustment buffer.

RESULTS

The overall median fluoride concentration for the 68 infant milks was 0.025 ppmF, with a wide range of 0.002-0.282 ppmF. Analysis revealed variation between composition and manufacturer, in addition to differences between measured and labeled fluoride concentration. Although all products contained low fluoride concentration, the fluoride concentrations for formula milks used within the hospital setting (0.029 ppmF) were statistically higher in comparison to the commercial formula milk (0.016 ppmF) and cow's milk (0.017 ppmF) products. The daily fluoride contribution from infant milks was low; 0.0034 mgF/kg body weight per day was estimated between birth and 6 months of age, further decreasing as intake of infant milk decreased with age.

CONCLUSIONS

Fluoride concentration of the analysed infant milks is low, providing minimal contribution towards total daily F intake and alone are unlikely to pose a threat for the development of dental fluorosis.

Association between estimated fluoride intake and dental caries prevalence among 5-year-old children in Korea

Background

The purposes of this study were to estimate the fluoride intake from food and drink in 5-year-old Korean children, and to measure the association between estimated fluoride intake and dental caries prevalence.

Methods

The study involved a secondary analysis of raw data from the 4^th Korea National Health and Nutrition Examination Survey (KNHANES; 2007–2009). The study subjects were 167 boys and 147 girls aged 5 years who had undergone both physical and nutritional examination as part of the survey. The KNHANES comprised a health questionnaire, a physical examination, and a nutritional examination. The nutritional examination of KNHANES consisted of 3 parts: a dietary life survey, a food-frequency questionnaire, and a food intake investigation. The food intake investigation used the 24-h recall method, with information being provided by the children’s parents. On the basis of this information, we evaluated the fluoride content in a total of 310 food items using the hexamethyldisiloxane (HMDS)-facilitated diffusion method, modified using Taves’ microdiffusion method. As part of the KNHANES survey, oral examinations were conducted at a mobile examination centre by trained dentists using dental mirrors under a fluorescent light. These examinations were performed using methods proposed by the World Health Organization.

Results

The dietary fluoride intake of 5-year-old Korean children was estimated to be 0.35 mg/day, or 0.016 mg/kg/day. The “decayed or filled surfaces” (dfs) indices of primary teeth were higher in children who had a lower dietary intake of fluoride. There was a significant inverse association between dietary fluoride intake and the prevalence of dental caries.

Conclusion

The inverse association between dietary fluoride intake levels and prevalence of dental caries implies that the introduction of community caries prevention programmes may be beneficial. Such programmes would include water fluoridation and a fluoride supplementation programme.

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.

Multivariate Statistical Analyses of Fluoride and Other Physicochemical Parameters in Groundwater Samples of Two Megacities in Asia: Lahore and Sialkot

The present study was carried out to evaluate the current status of contaminants and their sources in groundwater samples collected from Lahore and Sialkot. A total of 93 samples were collected from different localities of Lahore and Sialkot and analyzed for the determination of various physicochemical parameters. The results of the study revealed that mean fluoride and chloride contents of water samples from Lahore were higher than the values recommended by Pak-EPA and WHO whereas the mean nitrate and sulphate levels of these samples were well within the limits. The order observed for these physicochemical parameters from Lahore was Cl−> alkalinity >SO4-2>NO3-> F−. All the observed physicochemical parameters for water samples from Sialkot were found to be greater than those of Lahore, due to a more intensive industrial activity in Sialkot. The correlation study revealed the strongest correlation among conductance and alkalinity in samples from both cities. Fluoride and sulphate were found to be positively correlated in samples from Lahore and negatively correlated in samples from Sialkot. Multivariate analysis in terms of principle component analysis and cluster analysis furnished information about the sources of various parameters in groundwater samples.

Intraoral Fluoride-Releasing Devices: A Literature Review

Dental caries still continues to be a problem for majority of the individuals and it can be a serious problem for medically compromised, developmentally disabled and elderly individuals. Water fluoridation, systemic and topical fluorides are used for past many years to supply supplemental fluoride in order to combat dental caries. The latest fluoride research is investigating the use of slow-release devices for the long-term intraoral provision of fluoride. The present review addresses two main types of intraoral fluoride-releasing devices like the copolymer membrane device, glass device containing fluoride and some variations of these devices. These devices can significantly increase the salivary fluoride concentration without substantially affecting the urinary fluoride levels. A significant number of studies have confirmed that intraoral fluoride-releasing devices have great potential for use in preventing dental caries in children, high-caries-risk groups, and irregular dental attenders in addition to a number of other applications. As most of the studies done on these devices are in vitro and in vivo studies, more well-designed clinical trials are necessary to evaluate the results so that these devices can be used clinically.

How to cite this article

Gambhir RS, Kapoor D, Singh G, Singh J, Kakar H. Intraoral Fluoride-Releasing Devices: A Literature Review. World J Dent 2012;3(4):350-354.

Fluoride

Fluoride is a naturally occurring element with multiple implications for human health. This review discusses its metabolism and toxicity, along with the current understanding of the mechanism of action of fluoride and its role as a safe and effective agent in the prevention of dental caries. The relationship between excessive fluoride intake during periods of dental enamel formation and the development of dental fluorosis is also reviewed.

Fluoride content of water used to reconstitute infant formula

OBJECTIVE

To assess the fluoride content of water used to reconstitute infant formula by a Latino population living in the Indianapolis, Indiana, area.

BACKGROUND

Negligible as well as excessive fluoride can be detrimental to oral health. Estimates of fluoride intake and exposure for individuals may aid in the determination of their risk for developing dental fluorosis or caries.

METHODS

Interviews were conducted to determine brands of bottled water used to reconstitute infant formula. Identified brands were analyzed for fluoride concentration.

RESULTS

Of the 458 samples tested (from 20 brands), fluoride concentration ranged from 0.006 to 0.740 μg/mL. All brands but one had fluoride concentration less than 0.7 μg/mL, with 16 brands having less than 0.22 μg/mL. Most bottled waters analyzed in the study comply with the American Dental Association recommendation to prevent fluorosis. Comparisons made demonstrated that only waters targeted for infants and that are fluoridated do not comply with recent American Dental Association recommendations.

Fluoride content of bottled drinking waters available in Riyadh, Saudi Arabia

AIMS

This study aimed to examine the fluoride concentration of commercially available bottled water products in Riyadh, Saudi Arabia, and to assess the accuracy of the labeling of fluoride concentration on the tested brands.

METHODS

Fifteen randomly selected commercial brands of bottled water were obtained from supermarkets in Riyadh, Saudi Arabia. Three bottles of each brand were purchased, and fluoride content was measured using a combination fluoride-ion-selective electrode. The average reading for each brand was estimated and also compared with the fluoride content printed on the label.

RESULTS

The mean (±SD) fluoride content of the 12 local bottled water samples was 0.79 (±0.09) mg/L with a range from 0.5 to 0.83 mg/L. The mean fluoride concentration of the three imported brands was 0.67 (±0.02) mg/L with a narrow range of fluoride content (0.65-0.69). All tested samples mention the fluoride content on the label except two imported brands. Five samples showed a significant difference between our evaluation and stated content of fluoride that ranged between +0.46 and -0.2 mg/L.

CONCLUSIONS

Bottled drinking waters available in Riyadh, Saudi Arabia contain differing concentration of fluoride, but within a safe range for use as a source of systemic fluoride. In addition, the manufactures' labeling of fluoride content may be inaccurate.

Guidelines on the use of fluoride in children: an EAPD policy document

The EAPD strongly endorses that the daily use of fluoride should be a major part of any comprehensive preventive program for the control of dental caries in children. Regardless of the type of program, community or individually based, the suggested use of fluoride must be balanced between the estimation of caries risks and the possible risks for toxic effects of the fluorides. Such a preventive program should be re-evaluated at regular intervals and adapted to a patient's needs and risks. For the majority of European communities, the EAPD recommends the use of appropriate fluoride toothpaste in conjunction with good oral hygiene to be the basic fluoride regimen.

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.

Decline in the prevalence of dental fluorosis among South Australian children

BACKGROUND

The use of fluoride involves a balance between protection against dental caries and risk of dental fluorosis. Fluorosis in Australian children was highly prevalent in the early 1990 s. Policy measures were introduced to control fluoride exposure so as to reduce the prevalence of fluorosis.

OBJECTIVE

To evaluate the effectiveness of policy measures in reducing the prevalence of fluorosis among Australian children.

METHODS

A random sample of South Australian children born in 1989-1994 was selected in 2002/2003, stratified by fluoridation status and urban/rural residence. Children were targeted to form three successive birth cohorts: those children born in 1989/1990, 1991/1992 and 1993/1994, respectively. Fluoride exposures were assessed by questionnaire. One dentist examined 677 children for fluorosis using the Thylstrup and Fejerskov (TF) Index. Data were reweighted to reflect the state's child population. Case definitions of fluorosis were: having a TF score of 1+ (TF1+) or a TF score of 2+ (TF2+) on one or both maxillary central incisors.

RESULTS

A higher proportion of children in the later birth cohorts used low-concentration fluoridated toothpaste, and a smaller amount of toothpaste was used when they commenced toothbrushing. The fluorosis experience in this population was mostly very mild to mild. There was a significant decline in the prevalence of fluorosis across the three successive birth cohorts. The prevalence of fluorosis by TF1+ case definition declined from 34.7% to 22.1% and by TF2+ case definition from 17.9% to 8.3%. Risk factors for fluorosis were use of standard-concentration fluoridated toothpaste, an eating and/or licking toothpaste habit and exposure to fluoridated water.

CONCLUSION

The experience of fluorosis among the South Australian child population was mostly very mild to mild. There was a marked decline in the prevalence of fluorosis across the three successive birth cohorts. The decline was mainly linked with the reduction in exposure to fluoride from fluoridated toothpaste.

Fluoride concentrations in industrialized beverages consumed by children in the city of Bauru, Brazil

The increasing consumption of juices, soft drinks and teas among children has increased significantly fluoride ingestion at the age range of risk for development of dental fluorosis.

OBJECTIVE

The purpose of this study was to evaluate fluoride concentrations in some brands of industrialized beverages consumed by children in the city of Bauru, SP, Brazil.

MATERIAL AND METHODS

98 brands of beverages were analyzed, divided into 3 lots, comprising 36, 32 and 30 brands, respectively, for the first, second and third lots. Fluoride concentrations were determined by HMDS-facilitated diffusion, using a fluoride ion-specific electrode (Orion 9409).

RESULTS

Fluoride concentrations ranged between 0.04 and 1.76 microg F/mL. It was observed a wide variation in fluoride concentrations among the different brands, as well as the different lots of the same brand. There was no information on fluoride concentrations on the labels of any product.

CONCLUSIONS

Some of the products analyzed could contribute significantly to the total fluoride intake and, thus, be important risk factors for development of dental fluorosis, which indicates the need of controlling the production of these beverages with respect to fluoride concentration.

The prevalence of dental fluorosis in relation to water or salt fluoridation and reported use of fluoride toothpaste in school-age children

AIM

To compare prevalence of dental fluorosis (DF) in permanent teeth in children whose domestic water supply was fluoridated since birth with that in a community where fluoridated salt was available. A second aim was to analyse the relationship between DF prevalence and reported use of fluoride toothpaste in early childhood.

STUDY DESIGN

Cross-sectional study.

METHODS

A representative, random sample of 12-year-old children was examined in water fluoridated Dublin (Ireland) and non-water fluoridated Freiburg (Germany), where fluoridated salt was available. DF was recorded using the Dean's Index. The child's early experience of toothpaste use was recorded using a questionnaire.

RESULTS

377 children in Dublin and 322 children in Freiburg were examined. In Dublin 11.7% of the whole sample had a 'Questionable' level of DF, 9.8% had 'Very Mild', 3.7% had 'Mild' and 0.3% had 'Moderate' fluorosis. The corresponding percentages in Freiburg for all children were 10.9%, 4.0%, 3.4% and 0%. The results suggest that children in Dublin started brushing their teeth at an older age than in Freiburg, but no difference in DF levels was found between 'early' and 'late' users.

STATISTICS

Fisher's test revealed that the difference in DF levels between the two populations was statistically significant (p=0.03).

CONCLUSIONS

The prevalence of aesthetically important DF ('Mild' and 'Moderate') was low and similar in both communities and considerably lower than the expected level at water fluoridation concentrations of 1 ppm. However, the prevalence of 'Very Mild' fluorosis was twice as frequent in Dublin than in Freiburg.

Total fluoride intake and urinary excretion in 4–year–old Iranian children residing in low-fluoride areas

Knowledge of levels of fluoride ingestion and excretion is important in planning optimum fluoride therapy for young children. In previous literature, it has been assumed that only about one-third of ingested fluoride is excreted in young children. The aims of the present study were (a) to measure total fluoride intake, urinary fluoride excretion and fluoride balance, and (b) to investigate the effect of air temperature on fluoride intake and urinary fluoride excretion, in young children. Children (4 years old) living in a city, a small town and rural areas of Fars province, Iran, where drinking water contained 0·30–0·39 mg F/l, were invited to participate. Selection of subjects was by random sampling of kindergartens or health centres. The children were surveyed twice, once in summer and once in winter. Diet was obtained by 3 d diaries with interview. Samples of most foods and drinks were analysed for fluoride content. Ingestion of fluoride from toothpaste was estimated for each child. Each child's urine was collected over 24 h and analysed for fluoride content. Seventy-eight of the 116 volunteers completed all aspects of the study, which was conducted in 1995–6. For all children, the mean fluoride ingestion from diet was 0·390 (sd 0·122) mg/d or 0·028 (sd 0·008) mg/kg body weight per d. Fluoride ingestion from diet was higher in summer and higher in rural areas. The mean ingestion of fluoride from all sources was 0·426 (sd 0·126) mg/d and the mean fluoride urinary excretion was 0·339 (sd 0·100) mg/d. The difference between ingestion and urinary excretion was +0·087 (sd 0·143) mg, equivalent to 80 % excretion. Faecal excretion was not estimated. The results indicate fluoride retention at 4 years to be much lower than previously assumed.

Changes in dental fluorosis following the cessation of water fluoridation

OBJECTIVES

To determine changes in the prevalence of dental fluorosis, and in perceptions of aesthetic concerns due to dental fluorosis after water fluoridation ceased.

METHODS

Schoolchildren in second and third grades were examined in 1993-94, 1996-97 and 2002-03 to determine changes in the prevalence of dental fluorosis following fluoridation cessation of the public water supplies in 1992. The Thylstrup-Fejerskov Index (TFI) was used to quantify dental fluorosis. Perceptions of aesthetics were assessed by questionnaires which were sent home to parents. Residence and dental histories were confirmed on all children to determine the extent of exposure to all types of fluorides. Comparisons between the three surveys were used to establish the influence of fluoridated water and other fluoride sources on the occurrence and severity of dental fluorosis. Aesthetic ratings from parents were used to assess the aesthetic conditions of maxillary anterior teeth across the three surveys.

RESULTS

When fluoride was removed from the water supply in 1992, the prevalence and severity of TFI scores decreased significantly from the 1993-94 survey cycle when compared with the 1996-97 and 2002-03 survey cycles. The use of fluoride supplements and fluoride dentifrice also decreased during this study period. Analyses were unable to determine the influence of these different fluoride exposures on the changes in TFI scores over time. Comparisons of aesthetic ratings from parents between survey cycles failed to show any significant differences.

Fluoride dentifrice ingestion and fluorosis of the permanent incisors

BACKGROUND

Fluoride dentifrice is a primary means of preventing childhood caries, but it is also an important risk factor for fluorosis. The authors examine the influence of fluoride dentifrice ingestion on fluorosis of the permanent incisors.

METHODS

Participants in the Iowa Fluoride Study received questionnaires at regular intervals concerning fluoride sources. The authors assessed fluorosis using the fluorosis risk index. They estimated daily fluoride ingestion from dentifrice, diet and fluoride supplements and divided the amount by kilograms of body weight. The statistical analysis related fluoride ingestion to fluorosis in the permanent incisors.

RESULTS

In bivariate analyses, mild fluorosis was significantly related to ingestion of fluoride dentifrice at ages 24 and 36 months (P = .02 for both). After the authors adjusted for fluoride ingested from dietary sources, logistic regression showed a significant association between fluorosis and dentifrice ingestion at age 24 months (P = .04).

CONCLUSIONS

The study results suggest that fluorosis of the permanent incisors is influenced by ingestion of fluoride dentifrice during the first three years of life. Further research is needed to assess total intake of fluoride as a risk factor for fluorosis.

CLINICAL IMPLICATIONS

These results support recommendations that young children use only a pea-sized amount of dentifrice. Parents should supervise young children as they brush their teeth with fluoride dentifrice.

Conhecimento dos médicos pediatras e odontopediatras de Bauru e Marília a respeito de flúor

A proposta deste trabalho foi verificar o conhecimento dos médicos pediatras e odontopediatras, a respeito dos compostos fluoretados. Para tanto, foram visitados 91 médicos pediatras e 72 odontopediatras dos municípios de Bauru e Marília, que ao concordarem em participar da pesquisa receberam um questionário com 22 questões. O preenchimento e a devolução foram imediatos. Os dados obtidos foram analisados por meio de estatística descritiva, utilizando freqüências absolutas e relativas, representadas através de tabelas. Mediante a análise dos questionários, verificou-se que alguns polivitamínicos que contêm flúor são usualmente prescritos pelos médicos pediatras, ao passo que os géis, vernizes e soluções para bochecho são bastante empregados pelos odontopediatras. Não foi estabelecida relação entre o conhecimento e tempo de formado, a idade do profissional, a universidade de origem, a cidade em que trabalha e a área de atuação (particular, rede pública ou em ambos) desses profissionais. Os resultados obtidos sugerem que o conhecimento dos médicos pediatras e odontopediatras, das cidades de Bauru e de Marília, a respeito da presença de flúor em várias fontes de ingestão se mostrou insuficiente e, em algumas situações, preocupante, com relação à prevenção de fluorose dentária.

Fluoride Intake Levels in Relation to Fluorosis Development in Permanent Maxillary Central Incisors and First Molars

Gaps remain in our knowledge about the levels of fluoride intake that cause dental fluorosis. The purpose of this study was to report the fluorosis prevalence by levels of estimated fluoride intake in an effort to understand the importance of different levels of daily fluoride intake. As part of the longitudinal Iowa Fluoride Study, subjects were followed from birth to 36 months with questionnaires every 3-4 months to gather information on fluoride intake from various sources. Daily fluoride intake in mg per kg body weight (BW) was estimated from water, beverages and selected foods, fluoride supplements and dentifrice. Six hundred and twenty-eight subjects were examined for fluorosis on permanent incisors and first molars at about age 9 by two calibrated examiners using the Fluorosis Risk Index categories. Fluorosis prevalence rates were determined separately for maxillary central incisors and first molars by levels of estimated fluoride intake. There were significant positive associations between fluorosis prevalence and levels of fluoride intake. Cumulatively from birth to 36 months, average daily intake of 0.04 mg F/kg BW or less carried relatively low risk for fluorosis (12.9% for maxillary central incisors, 6.8% for first molars). Average daily intake of 0.04-0.06 mg F/kg BW showed a significantly elevated risk for fluorosis (23.0% for maxillary central incisors, 14.5% for first molars), while fluorosis risk was even higher for average intake above 0.06 mg F/kg BW (38.0% for maxillary central incisors, 32.4% for first molars). The study suggests that fluorosis prevalence is related to elevated fluoride intake when averaged over the first 3 years of life, but is even more strongly related to fluoride intake that is elevated for all of the first 3 years of life.

Association of diet with dental caries in preschool children

This article updates the evidence linking dietary factors to dental caries in preschool children and recommends dietary approaches to reduce caries risk. Along with nutritional factors, a comprehensive approach to preventing dental caries in preschool children must include good oral hygiene, appropriate use of fluorides, and access to preventive and restorative dental care.

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.

Total and acid-soluble fluoride content of infant cereals, beverages and biscuits from Brazil

Total fluoride (TF) and HCl 0.01 M ('gastric juice')-soluble fluoride (SF) were analysed in infant foods, beverages and calcium-rich biscuits. Samples were divided into seven categories: children cereals (A), chocolate-flavoured milk (B), soy beverages (C), filled biscuits (D), non-filled biscuits (E), wafer biscuits (F) and corn starch biscuits (G). Mean TF concentrations +/- SD (amplitude, unit microgram F ml-1 or microgram F g-1) were: (A) 4.25 +/- 3.04 (0.20-7.84, n = 6); (B) 0.34 +/- 0.47 (0.05-1.27, n = 6); (C) 0.15 +/- 0.07 (0.09-0.29, n = 8); (D) 8.44 +/- 1.76 (7.65-10.47, n = 4); (E) 12.41 +/- 1.15 (10.69-13.68, n = 4); (F) 0.35 +/- 0 (0.34-0.36, n = 4) and (G) 7.77 +/- 1.12 (6.86-8.68, n = 2). Five samples of cereals, one sample of chocolate-flavoured milk and 10 samples of biscuits were analysed for SF. In cereals analysed for SF, all fluoride was soluble, while for the chocolate-flavoured milk, approximately 50% of TF was soluble. Regarding the biscuits analysed for SF approximately 20% of TF was soluble. It was observed that some of the cereals and beverages, and most of the biscuits analysed, might be important contributors to total daily fluoride intake. When consumed just once per day, cereals and beverages might supply up to 25% of the maximum recommended daily fluoride intake (0.07 mg F kg-1 body weight) for a 2-year-old child (12 kg). For the filled, non-filled and corn starch biscuits, when 3, 32 or 20 units of them, respectively, are consumed just once per day, they may supply up to 16% of the maximum recommended daily fluoride intake. However, only approximately 25% of fluoride absorption occurs from the stomach and 75% from the small intestine. Therefore, a higher fluoride bioavailability is possible.

The rational use of fluoride toothpaste

Well-formulated fluoride toothpastes are clinically proven to prevent and control dental caries. They may also be a risk factor in the aetiology of dental fluorosis. This review considers the available evidence to support the appropriate use of fluoride toothpaste to maximise the benefit and minimise the risk. Three factors have an important influence on the anticaries efficacy of fluoride toothpaste, namely concentration, frequency of brushing and post brushing rinsing behaviour. The evidence suggests that low-fluoride (<600 ppm F) toothpastes provide less caries protection than standard (1,000 ppm F) or high (1,500 ppm F) concentration formulations. However, low-fluoride toothpastes are appropriate for very young children (under 7 years) at low caries risk, particularly if living in fluoridated areas. For other young children, higher concentrations of fluoride should be used. Brushing should be recommended twice daily, whilst rinsing with large volumes of water should be discouraged. Small amounts of toothpaste are comparable in efficacy to large amounts. The risk of fluorosis is associated with the ingestion of high doses of fluoride during tooth development and consequently only young children are at risk. The variability in the dose of fluoride ingested is mainly a function of the amount used, less so its concentration. To minimise fluorosis risk, parents should be advised to use only a pea-sized amount of toothpaste and encourage spitting out of excess. It is concluded that by using fluoride toothpastes appropriately, the benefits can be maximised and the risks of fluorosis minimised.

Fluoride content in bottled waters, juices and carbonated soft drinks in Mexico City, Mexico

OBJECTIVE

The objective of this study was to analyse 283 samples of soft drinks available in the metropolitan market of Mexico City, Mexico: 105 juices, 101 nectars, 57 carbonated drinks and 20 bottled waters.

MATERIALS AND METHODS

Samples of the beverages were analysed using an Orion 720A potentiometer and an Orion 9609BN F ion-specific electrode.

RESULTS

Fluoride concentration in the above-mentioned products ranged from 0.07 to 1.42 p.p.m. It was found that fluoride concentrations varied according to the brand, flavour and presentation of the product. The highest mean concentration of fluoride was found in the juices and cola drinks (0.67 +/- 0.38 and 0.49 +/- 0.41 p.p.m., respectively). The mean fluoride concentration for carbonated drinks was 0.43 +/- 0.36 p.p.m. Bottled waters had a fluoride concentration of 0.21 +/- 0.08 p.p.m.

CONCLUSIONS

The findings suggest that fluoride ingested through bottled drinks represents an important part of the total fluoride ingested by the population. In view of the wide variation of fluoride concentration in the tested products, it is necessary to implement regulatory guidelines for controlling its concentration in order to prevent dental fluorosis.

Fluoride mouth rinsing proficiency of Japanese preschool-aged children

AIM

To determine whether Japanese preschool-aged children swallow fluoride solution while rinsing and how much fluoride was retained in the mouth after rinsing.

METHODS

The subjects were 769 children who participated in a school-based fluoride mouth rinse programme (FMR) using 0.05% sodium fluoride solution daily. The group of younger, mean age of 4 years and 10 months, experienced the FMR for two months, and the group of older children, mean age of 5 years and 4 months, did it for at least 8 months, rinsing for a minute using 7 ml of the solution. The amount of fluoride retained in the mouth was estimated as the amount present in the net rinsing solution prepared minus what returned to the solution expectorated.

RESULTS

No child swallowed all the solution. The rate of fluoride retained was 12.0% (mean = 0.19 mg) in the younger group and 10.7% (mean = 0.17 mg) in the older. Only six children retained over 0.5 mg of fluoride. With the extra survey using weekly intervals, the amount retained was below 0.5 mg in all children.

CONCLUSION

That Japanese preschoolaged children could perform fluoride mouth rinsing safely and efficiently.

Fluoride and aluminum in teas and tea-based beverages

OBJECTIVE: To evaluate fluoride and aluminum concentration in herbal, black, ready-to-drink, and imported teas available in Brazil considering the risks fluoride and aluminum pose to oral and general health, respectively. METHODS: One-hundred and seventy-seven samples of herbal and black tea, 11 types of imported tea and 21 samples of ready-to-drink tea were divided into four groups: I-herbal tea; II-Brazilian black tea (Camellia sinensis); III-imported tea (Camellia sinensis); IV-ready-to-drink tea-based beverages. Fluoride and aluminum were analyzed using ion-selective electrode and atomic absorption, respectively. RESULTS: Fluoride and aluminum levels in herbal teas were very low, but high amounts were found in black and ready-to-drink teas. Aluminum found in all samples analyzed can be considered safe to general health. However, considering 0.07 mg F/kg/day as the upper limit of fluoride intake with regard to undesirable dental fluorosis, some teas exceed the daily intake limit for children. CONCLUSIONS: Brazilian and imported teas made from Camellia sinensis as well as some tea-based beverages are sources of significant amounts of fluoride, and their intake may increase the risk of developing dental fluorosis.

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.

Fluorine content of several brands of chocolate bars and chocolate cookies found in Brazil

Chocolate bars and chocolate cookies are foodstuffs highly appreciated by children. The possibility of having fluorine (F) among their components, associated with an excessive consumption, may make them decisive contributors to the total daily F intake. Thus, they could participate in the establishment of dental fluorosis. The aim of this study was to analyze the fluorine concentration [F] of the chocolates bars (CB) Baton, Confeti, Garoto Ball, Kinder Ovo, M&M s, Milkybar, Nescau, Nescau Ball, Surpresa, Surpresa Bichos, Tortuguita; and of the chocolate cookies (CC) Danyt s, Hipop , Nescau, Passatempo, Pokémon, S tio do Pica-Pau Amarelo and Trakinas. Samples were purchased in Bauru, São Paulo, Brazil. Three grams of each product were previously ashed at 525 C (CB and cookies fillings) and at 550 C (cookies dough), during 4 hours. Fluorine was separated from the ash by hexamethyldisiloxane (HMDS)-facilitated diffusion. Fluorine analysis was carried out with the specific electrode. Mean [F]s SD and amplitude (unit mg/g) were: CB = 0.30 0.45 (0.07 - 1.60, n = 12) and CC = 1.08 2.64 (0.04 - 7.10, n = 7). It was concluded that some of the analyzed foods may be important contributors to the total daily F intake. As for the product that had the highest [F] (Danyt s), when only 3 units are consumed just once a day, they may supply up to 40% of the maximum recommended daily F intake (0.07 mg/kg body weight) for a 2-year-old child (12 kg). The [F] in these products should be informed on their labels.

Fluoride content of several breakfast cereals and snacks found in Brazil

Breakfast cereals and snacks are foodstuffs highly appreciated by children, and the possibility that they contain substantial amounts of fluoride, associated with their widespread consume, may make them important contributors to the total daily fluoride intake. The aim of this study was to analyze the fluoride content on several breakfast cereals (A) and snacks (B) purchased in Brazil. The analysis were made after HMDS-facilitated diffusion (Taves) using the ion-specific electrode (9609). Mean fluoride concentrations ± SD (range, unit mg F/g) were: A= 0.76 ± 0.60 (0.08-1.86, n=15) and B= 0.32 ± 0.09 (0.22-0.55, n=18). Our results suggest that the total amount of fluoride available in some products may contribute to the total daily fluoride intake. The product labels should provide information on their fluoride content to prevent fluorosis at the age of risk.

Current and future role of fluoride in nutrition

Fluoride continues to be the cornerstone of dental caries prevention in North America and throughout the world, and there are a variety of sources of fluoride that may contribute to the dietary intakes of fluoride. Although the severe effect of chronic exposures to high levels of fluoride--skeletal fluorosis--is extremely rare in North America, dental fluorosis has become more prevalent. To address the increase in dental fluorosis prevalence, recommendations have been made to reduce fluoride ingestion early in life. These recommendations have included the introduction of lower concentration fluoride dentifrice for use by young children, labeling of the fluoride concentration of bottled water, and revised fluoride supplement guidelines to reduce or eliminate their use. Because our knowledge is incomplete regarding the amount, duration, and timing of fluoride ingestion that can result in dental fluorosis, however, further research is clearly needed before definitive recommendations can be made regarding the use of fluorides, including recommended intakes of fluoride in the diet.

Practitioner's guide to fluoride

The current health care trend is to provide evidence-based recommendations and treatment. Many literature reviews have shown fluoride's effectiveness against caries. The current use of fluoride in the prevention of dental caries is based on community, professional, and individual strategies. Personalized fluoride regimens should include a risk analysis and a review of the patient's current fluoride exposure. The future of fluoride may be found in its slow release and retention in the oral cavity through various modalities. Because of the many uncertainties still associated with fluoride, further research is needed.

[Dental fluorosis in Brazil: a critical review]

This paper discusses dental fluorosis as a relevant public health problem, using a review of epidemiological studies published in the last 10 years on the disease's prevalence, severity, and risk factors. The results suggest that there are already more cases than expected, although few studies refer to major severity. Thus, measures are needed for the prevention and surveillance of dental fluorosis.