Estimation of optimal concentration of fluoride in drinking water under conditions prevailing in Chile

Water fluoridation for the prevention of dental caries

BACKGROUND

Dental caries is a major public health problem in most industrialised countries, affecting 60% to 90% of school children. Community water fluoridation (CWF) is currently practised in about 25 countries; health authorities consider it to be a key strategy for preventing dental caries. CWF is of interest to health professionals, policymakers and the public. This is an update of a Cochrane review first published in 2015, focusing on contemporary evidence about the effects of CWF on dental caries.

OBJECTIVES

To evaluate the effects of initiation or cessation of CWF programmes for the prevention of dental caries. To evaluate the association of water fluoridation (artificial or natural) with dental fluorosis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and four other databases up to 16 August 2023. We also searched two clinical trials registers and conducted backward citation searches.

SELECTION CRITERIA

We included populations of all ages. For our first objective (effects of initiation or cessation of CWF programmes on dental caries), we included prospective controlled studies comparing populations receiving fluoridated water with those receiving non-fluoridated or naturally low-fluoridated water. To evaluate change in caries status, studies measured caries both within three years of a change in fluoridation status and at the end of study follow-up. For our second objective (association of water fluoridation with dental fluorosis), we included any study design, with concurrent control, comparing populations exposed to different water fluoride concentrations. In this update, we did not search for or include new evidence for this objective.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. For our first objective, we included the following outcomes as change from baseline: decayed, missing or filled teeth ('dmft' for primary and 'DMFT' for permanent teeth); decayed, missing or filled tooth surfaces ('dmfs' for primary and 'DMFS' for permanent teeth); proportion of caries-free participants for both primary and permanent dentition; adverse events. We stratified the results of the meta-analyses according to whether data were collected before or after the widespread use of fluoride toothpaste in 1975. For our second objective, we included dental fluorosis (of aesthetic concern, or any level of fluorosis), and any other adverse events reported by the included studies.

MAIN RESULTS

We included 157 studies. All used non-randomised designs. Given the inherent risks of bias in these designs, particularly related to management of confounding factors and blinding of outcome assessors, we downgraded the certainty of all evidence for these risks. We downgraded some evidence for imprecision, inconsistency or both. Evidence from older studies may not be applicable to contemporary societies, and we downgraded older evidence for indirectness. Water fluoridation initiation (21 studies) Based on contemporary evidence (after 1975), the initiation of CWF may lead to a slightly greater change in dmft over time (mean difference (MD) 0.24, 95% confidence interval (CI) -0.03 to 0.52; P = 0.09; 2 studies, 2908 children; low-certainty evidence). This equates to a difference in dmft of approximately one-quarter of a tooth in favour of CWF; this effect estimate includes the possibility of benefit and no benefit. Contemporary evidence (after 1975) was also available for change in DMFT (4 studies, 2856 children) and change in DMFS (1 study, 343 children); we were very uncertain of these findings. CWF may lead to a slightly greater change over time in the proportion of caries-free children with primary dentition (MD -0.04, 95% CI -0.09 to 0.01; P = 0.12; 2 studies, 2908 children), and permanent dentition (MD -0.03, 95% CI -0.07 to 0.01; P = 0.14; 2 studies, 2348 children). These low-certainty findings (a 4 percentage point difference and 3 percentage point difference for primary and permanent dentition, respectively) favoured CWF. These effect estimates include the possibility of benefit and no benefit. No contemporary data were available for adverse effects. Because of very low-certainty evidence, we were unsure of the size of effects of CWF when using older evidence (from 1975 or earlier) on all outcomes: change in dmft (5 studies, 5709 children), change in DMFT (3 studies, 5623 children), change in proportion of caries-free children with primary dentition (5 studies, 6278 children) or permanent dentition (4 studies, 6219 children), or adverse effects (2 studies, 7800 children). Only one study, conducted after 1975, reported disparities according to socioeconomic status, with no evidence that deprivation influenced the relationship between water exposure and caries status. Water fluoridation cessation (1 study) Because of very low-certainty evidence, we could not determine if the cessation of CWF affected DMFS (1 study conducted after 1975; 2994 children). Data were not available for other review outcomes for this comparison. Association of water fluoridation with dental fluorosis (135 studies) The previous version of this review found low-certainty evidence that fluoridated water may be associated with dental fluorosis. With a fluoride level of 0.7 parts per million (ppm), approximately 12% of participants had fluorosis of aesthetic concern (95% CI 8% to 17%; 40 studies, 59,630 participants), and approximately 40% had fluorosis of any level (95% CI 35% to 44%; 90 studies, 180,530 participants). Because of very low-certainty evidence, we were unsure of other adverse effects (including skeletal fluorosis, bone fractures and skeletal maturity; 5 studies, incomplete participant numbers).

AUTHORS' CONCLUSIONS

Contemporary studies indicate that initiation of CWF may lead to a slightly greater reduction in dmft and may lead to a slightly greater increase in the proportion of caries-free children, but with smaller effect sizes than pre-1975 studies. There is insufficient evidence to determine the effect of cessation of CWF on caries and whether water fluoridation results in a change in disparities in caries according to socioeconomic status. We found no eligible studies that report caries outcomes in adults. The implementation or cessation of CWF requires careful consideration of this current evidence, in the broader context of a population's oral health, diet and consumption of tap water, movement or migration, and the availability and uptake of other caries-prevention strategies. Acceptability, cost-effectiveness and feasibility of the implementation and monitoring of a CWF programme should also be taken into account.

External control of fluoridation in public water supply systems in the state of Goiás, Brazil

The addition of fluoride to the public water supply is a method used for reducing tooth decay. In this sense, the control of fluoridation is important for maintaining its efficiency and, at the same time, for avoiding the risk of fluorosis as a result of the consumption of water with excess of fluoride. The objective of this study was to evaluate the adequacy of fluoride levels in the water distributed to populations of the state of Goiás, Brazil. Towards this aim, 5,039 water samples collected between 2011 and 2013 in 225 municipalities of the state of Goiás were analyzed for fluoride level. The results were assessed with regard to season, type of water source and geographic location. Fluoride levels were found to vary between complete absence and 2.5 mg F/L, with 28.2% of the samples being between 0.6 and 0.8 mg F/L, and 39.1% between 0.55 and 0.84 mg F/L. The rainy season produced a greater number of atypical results and higher values than the dry period. The systems supplied by groundwater sources were shown to have a limited control of fluoride concentration compared to systems supplied by surface water sources. Lower concentrations of fluoride were found in samples collected in the North and East Mesoregions of Goiás, with less than 7.5% being between 0.6 and 0.8 mg F/L, which systems are mainly supplied by groundwater sources with fluoride addition .

Autotransplantation of a Strange Positioned Impacted Central Incisor in a surgically Prepared Socket: A Miracle Esthetic Concept

Esthetics is a prime concern for a young lady. Any anomaly in the anterior tooth may create anxiety and depression. This anxiety and depression may hamper her married life and overall personality. This case report reveals an unerupted right central incisor situated in a strange position, creating space in the maxillary anterior region and giving an unesthetic appearance. Autotransplantation is a method of choice for a strangely positioned impacted central incisor in a new appropriate site. This method offers a new treatment option for some clinical situations if orthodontic approach is not possible. It permits tooth movement to a distant or the opposite side of the same dental arch as well as to the opposite jaw. This procedure also offers potential benefits of reestablishment of normal alveolar process development, esthetics, functions, and arch integrity. This procedure has the potential to become a viable alternative treatment plan for young patients of low socioeconomic status, allowing the reestablish-ment and restoration of a missing tooth and their functions. This article discusses methods of auto-reimplantation of a tooth in a fresh surgically prepared socket, its biological principle, and establishment of functions, esthetics, and phonetics.

Gorlin-Goltz Syndrome: A Rare Case Report of a 11-Year-Old Child

Gorlin-Goltz Syndrome, also known as nevoid basal cell carcinoma syndrome (NBCCS), is an autosomal dominant trait caused due to mutations in the patched tumor suppressor gene (PTCH) gene found on the long arm of chromosome 9. The syndrome is characterized by the presence of odontogenic keratocysts (OKCs), basal cell carcinomas, and skeletal malformations. Early diagnosis of the syndrome can be done by pedodontist as OKC is one of the early manifestations of the syndrome. Early diagnosis and treatment is important for long-term prognosis of the syndrome by reducing the severity of cutaneous carcinomas and deformities due to jaw cyst. The present case describes an 11-year-old patient with some typical features of NBCCS, which were diagnosed through its oral and maxillofacial manifestations. This case emphasizes the importance of pedodontist in early recognition of the syndrome.

HOW TO CITE THIS ARTICLE

Tandon S, Chauhan Y, Sharma M, Jain M. Gorlin-Goltz Syndrome: A Rare Case Report of a 11-Year-Old Child. Int J Clin Pediatr Dent 2016;9(3):264-268.

Prevalence of Dental Fluorosis and associated Risk Factors in Bagalkot District, Karnataka, India

INTRODUCTION

An earlier epidemiological study by these authors revealed fluorosis at very low levels of fluoride concentrations in drinking water.

AIM

The objective of present study was to investigate risk factors of dental fluorosis in permanent teeth in the villages of northern Karnataka, India.

MATERIALS AND METHODS

The present survey was carried out in three villages of Hungund Taluk, Bagalkot District, Karnataka, India, with the fluoride concentration of 0.136, 0.381, and 1.36 ppm. Children aged between 9 and 15, with permanent teeth, were examined for dental fluorosis using Dean's index, as per WHO criteria. Required relevant information regarding risk factors was obtained through a questionnaire.

STATISTICAL ANALYSIS

Data entry and analysis were performed using SPSS for Windows 16.0. Comparison of means of different indices by the three groups was performed using ANOVA and t-test (p < 0.05). Bivariate analysis was performed to identify significant risk factors that affected prevalence and severity of dental fluorosis. Those variables showing a statistically significant association (p < 0.05) on χ2 were entered into multiple logistic regressions to assess their independent effects.

RESULTS

In this study, we analyzed risk factors for both prevalence and severity of fluorosis. From multiple logistic regression analysis, only fluoride concentration in drinking water was found significant with prevalence of fluorosis and only nutritional status showed significant association with severity of fluorosis.

CONCLUSION

Presence or absence of dental fluorosis in permanent teeth was significantly associated with fluoride concentration in drinking water. Once present, its severity was determined by nutritional status of the children - malnourished children exhibiting severe form of fluorosis.

HOW TO CITE THIS ARTICLE

Mahantesha T, Dixit UB, Nayakar RP, Ashwin D Ramagoni NK, Ellore VPK. Prevalence of Dental Fluorosis and associated Risk Factors in Bagalkot District, Karnataka, India. Int J Clin Pediatr Dent 2016;9(3):256-263.

Water fluoridation for the prevention of dental caries

BACKGROUND

Dental caries is a major public health problem in most industrialised countries, affecting 60% to 90% of school children. Community water fluoridation was initiated in the USA in 1945 and is currently practised in about 25 countries around the world; health authorities consider it to be a key strategy for preventing dental caries. Given the continued interest in this topic from health professionals, policy makers and the public, it is important to update and maintain a systematic review that reflects contemporary evidence.

OBJECTIVES

To evaluate the effects of water fluoridation (artificial or natural) on the prevention of dental caries.To evaluate the effects of water fluoridation (artificial or natural) on dental fluorosis.

SEARCH METHODS

We searched the following electronic databases: The Cochrane Oral Health Group's Trials Register (to 19 February 2015); The Cochrane Central Register of Controlled Trials (CENTRAL; Issue 1, 2015); MEDLINE via OVID (1946 to 19 February 2015); EMBASE via OVID (1980 to 19 February 2015); Proquest (to 19 February 2015); Web of Science Conference Proceedings (1990 to 19 February 2015); ZETOC Conference Proceedings (1993 to 19 February 2015). We searched the US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization's WHO International Clinical Trials Registry Platform for ongoing trials. There were no restrictions on language of publication or publication status in the searches of the electronic databases.

SELECTION CRITERIA

For caries data, we included only prospective studies with a concurrent control that compared at least two populations - one receiving fluoridated water and the other non-fluoridated water - with outcome(s) evaluated at at least two points in time. For the assessment of fluorosis, we included any type of study design, with concurrent control, that compared populations exposed to different water fluoride concentrations. We included populations of all ages that received fluoridated water (naturally or artificially fluoridated) or non-fluoridated water.

DATA COLLECTION AND ANALYSIS

We used an adaptation of the Cochrane 'Risk of bias' tool to assess risk of bias in the included studies.We included the following caries indices in the analyses: decayed, missing and filled teeth (dmft (deciduous dentition) and DMFT (permanent dentition)), and proportion caries free in both dentitions. For dmft and DMFT analyses we calculated the difference in mean change scores between the fluoridated and control groups. For the proportion caries free we calculated the difference in the proportion caries free between the fluoridated and control groups.For fluorosis data we calculated the log odds and presented them as probabilities for interpretation.

MAIN RESULTS

A total of 155 studies met the inclusion criteria; 107 studies provided sufficient data for quantitative synthesis.The results from the caries severity data indicate that the initiation of water fluoridation results in reductions in dmft of 1.81 (95% CI 1.31 to 2.31; 9 studies at high risk of bias, 44,268 participants) and in DMFT of 1.16 (95% CI 0.72 to 1.61; 10 studies at high risk of bias, 78,764 participants). This translates to a 35% reduction in dmft and a 26% reduction in DMFT compared to the median control group mean values. There were also increases in the percentage of caries free children of 15% (95% CI 11% to 19%; 10 studies, 39,966 participants) in deciduous dentition and 14% (95% CI 5% to 23%; 8 studies, 53,538 participants) in permanent dentition. The majority of studies (71%) were conducted prior to 1975 and the widespread introduction of the use of fluoride toothpaste.There is insufficient information to determine whether initiation of a water fluoridation programme results in a change in disparities in caries across socioeconomic status (SES) levels.There is insufficient information to determine the effect of stopping water fluoridation programmes on caries levels.No studies that aimed to determine the effectiveness of water fluoridation for preventing caries in adults met the review's inclusion criteria.With regard to dental fluorosis, we estimated that for a fluoride level of 0.7 ppm the percentage of participants with fluorosis of aesthetic concern was approximately 12% (95% CI 8% to 17%; 40 studies, 59,630 participants). This increases to 40% (95% CI 35% to 44%) when considering fluorosis of any level (detected under highly controlled, clinical conditions; 90 studies, 180,530 participants). Over 97% of the studies were at high risk of bias and there was substantial between-study variation.

AUTHORS' CONCLUSIONS

There is very little contemporary evidence, meeting the review's inclusion criteria, that has evaluated the effectiveness of water fluoridation for the prevention of caries.The available data come predominantly from studies conducted prior to 1975, and indicate that water fluoridation is effective at reducing caries levels in both deciduous and permanent dentition in children. Our confidence in the size of the effect estimates is limited by the observational nature of the study designs, the high risk of bias within the studies and, importantly, the applicability of the evidence to current lifestyles. The decision to implement a water fluoridation programme relies upon an understanding of the population's oral health behaviour (e.g. use of fluoride toothpaste), the availability and uptake of other caries prevention strategies, their diet and consumption of tap water and the movement/migration of the population. There is insufficient evidence to determine whether water fluoridation results in a change in disparities in caries levels across SES. We did not identify any evidence, meeting the review's inclusion criteria, to determine the effectiveness of water fluoridation for preventing caries in adults.There is insufficient information to determine the effect on caries levels of stopping water fluoridation programmes.There is a significant association between dental fluorosis (of aesthetic concern or all levels of dental fluorosis) and fluoride level. The evidence is limited due to high risk of bias within the studies and substantial between-study variation.

Investigation of the value of a photographic tool to measure self-perception of enamel opacities

BACKGROUND

The standard measurement of oral conditions that are mainly of cosmetic concern can be carried out by a trained clinical professional, or they can be assessed and reported by the individuals who may have the condition or be aware of others who have it. Enamel opacities of anterior teeth are examples of such a condition. At a public health level the interest is only about opacities that are of aesthetic concern, so the need for an index that records opacities that the public perceive to be a problem is clear. Measurement methods carried out by highly trained professionals, using unnatural conditions are not indicated at this level. This study reports on the testing of a novel epidemiological tool that aims to report on the prevalence and impact of self-perceived enamel opacities in a population of young adolescents.

METHODS

A dental health survey was carried out using a random sample of 12-year-old school pupils during 2008/09 by Primary Care Organisations (PCOs) in England. This included the use of a novel self-perception tool which aimed to measure individual's self-perception of the presence and impact of enamel opacities to produce population measures. This tool comprised questions asking about the presence of white marks on their teeth and whether these marks bothered the volunteers and a sheet of grouped photographs of anterior teeth showing opacities ranging from TF 0, TF 1-2 to TF 2-3. Volunteers were asked which of the groups of photographs looked more like their own teeth. Examining teams from a convenience sample of 3 PCOs from this survey agreed to undertake additional measurements to assess the value of the self-perception tool. Volunteer pupils were asked the questions on a second occasion, some time after the first and clinical examiners recorded their assessments of the most closely matching set of photographs of the volunteers on two occasions.

RESULTS

The tool was feasible to use, with 74% of pupils making a response to the first question about the presence of white marks on front teeth, 94% to the second (do these marks bother you?) and 79% to the third about which set of images most closely matched the volunteer's own, with regard to white marks. Responses to these sequential questions showed coherence with pupils who perceived themselves as having white marks on their teeth being more likely to select images that showed teeth with opacities to match with their appearance. Pupils who reported themselves concerned about their white marks were the most likely to select images with the most severe opacities. Repeatability was good among pupils (Kappa = 0.65) and very good among examiners (Kappa = 0.87). Agreement levels between pupil's and examiner's choice of images was poor as examiners were less likely than pupils to select images that showed more severe levels of mottling.

CONCLUSIONS

With regard to feasibility, coherence and repeatability the standardised epidemiological tool under scrutiny, with operator training, appears to be a suitable method for measuring the prevalence and impact of self-perceived enamel opacities in a population of young adolescents.

Fluoride intake from drinking water and dentifrice by children living in a tropical area of Brazil

Objective:

To assess fluoride (F^-) intake from water and toothpaste by children aged 18 to 36 months and to monitor the F^- concentrations in the drinking water system in a tropical city of Brazil.

Methods:

Children (n=58) aged 18-36 months, all lifetime residents of Penedo, state of Alagoas, Brazil, participated in this study. Water F^- analyses were carried out in 7 different occasions at least a week apart. For 2 days all the water drunk by each child was accounted for. Fluoride intake from water for each child was estimated using the mean F^- concentration of water in 7 different occasions. Fluoride intake from toothpaste was estimated by subtracting the recovered post-brushing F^- from the original amount placed in the toothbrush. The F^- intake from water and toothpaste was estimated by dividing the total amount of F^- ingested by the weight of each child.

Results:

The mean F^- concentration in the drinking water was 0.94 ppm (mean range 0.78-1.1 ppm), which is above the 0.7 ppm recommended for this area of Brazil. Mean total F^- intake from water and toothpaste was 0.128 mg F^-/Kg Body Weight/day. The daily means of F^- intake from water and toothpaste were 0.021 and 0.107 mg F^-/Kg Body Weight, respectively. Ninety six percent of children showed F^- intake above 0.07 mg F^-/Kg Body Weight/day.

Conclusions:

Children in Penedo are at risk for developing dental fluorosis due to high F^- intake from fluoridated toothpastes. Water fluoridation showed low contribution to the total F^- intake. However, high water F^- concentrations in the water indicate the need of surveillance of the artificial water fluoridation system.

Potential exposure and risk of fluoride intakes from tea drinks produced in Taiwan

Tea is the second most commonly consumed drink in the world. Excess fluoride intakes from tea drinks may cause health effects. This work assesses infusible fluoride levels in popular tea sold in Taiwan and evaluates potential exposure factors. Lungjing, pouchong, tienguanyin, oolong, pureh, and black tea specimens were purchased from different counties in Taiwan. Fluoride levels were evaluated in one complete cycle of tea making as well as at different calcium carbonate contents in water, with glass or porcelain teapots, and with/without adding sugar. Oolong tea leaves in each manufacturing step were also analyzed for infusible fluoride. Potential fluoride intakes and risks are estimated based on a national survey. Among six kinds of tea, black tea had the highest fluoride concentrations (8.64+/-2.96 mg/l), whereas pureh (1.97+/-2.70 mg/l) had the lowest levels. Higher percentages of infusible fluoride can be rinsed away from tea leaves curved lengthways compared to those curved end-to-end in the first 2.5 min. The use of glass or porcelain teapots and calcium carbonate content (up to 400 mg/l) in water would not affect infusible fluoride levels, whereas adding sugar increased the infusible fluoride in the first few minutes. In addition, it was found that the critical step during the manufacturing process affecting the percentage of infusible fluoride was ball rolling rather than fermentation. Furthermore, intakes of high amounts (> or =5 l/week) of certain tea may result in excess risks of dental or skeletal fluorosis. Tea lovers could be exposed to excess fluoride and may be at risk of fluorosis.

Dental fluorosis in children attending basic health units

OBJECTIVES: The purpose of this study was to determine the prevalence and severity of dental fluorosis among patients attending basic health units in Londrina. METHODS: Five basic health units of the urban area were randomly selected and 434 children attending these units, born between 1986 and 1989 (9 to 12 years of age), were examined. Diagnosis of dental fluorosis was performed by means of the Thylstrup and Fejerskov (TF) Index. Oral examinations were carried out by 5 previously trained dentists with the patients lying in the dental chair, under artificial light, preceded by prophylaxis, isolation with cotton rolls and air-drying of the teeth. Ten percent of the sample was reexamined and an almost perfect agreement on diagnostic criteria was obtained either on the intra-examiner or inter-examiner evaluation (K=1.00, p<0.0001). RESULTS: The observed prevalence of dental fluorosis was 91.0%, and 87.8% of the individuals were classified as TF grade 2 or less. CONCLUSIONS: Despite of the low severity, the high prevalence observed shows the need for regular screening of dental fluorosis in Londrina; establishment of procedures to prevent the overutilization of fluoride both by the professionals and the population; sanitary surveillance of fluoride levels in water supply and also in all sources of fluoride available; besides the need for further studies to understand the factors associated to dental fluorosis among children living in Londrina.

Determining the optimal concentration of fluoride in drinking water in Pakistan

OBJECTIVES

This study was designed to determine the optimal concentrations of fluoride for drinking water in Pakistan. Clinical dental examination of 1020 school children aged 12 years was carried out in 19 cities of Pakistan. Correlation between concentrations of water fluoride, caries and fluorosis was investigated by analyzing the data on fluoride concentrations in drinking water in the sampled population for which the caries and the fluorosis levels were also measured.

METHODS

The optimal level of fluoride in drinking water is universally calculated by applying the equation of Galagan and Vermillion, which permits the calculation of water intake as a function of temperature. The annual mean maximum temperatures (AMMT) recorded during the last 5 years were collected from the meteorological centres of the 28 divisional headquarter stations. The average AMMT of Pakistan is 29 degrees C at which the optimal fluoride in drinking water of Pakistan was calculated to be 0.7 ppm. As drinking habits differ in various parts of the world, determination of optimal concentration of fluoride for drinking water in Pakistan was performed using a modified Galagan and Vermillion equation, which applies a correction factor of 0.56 to the equation. The optimal fluoride in drinking water in Pakistan using this modified equation was determined to be 0.39 ppm.

RESULTS

Observation of the correlation showed that a fluoride concentration of 0.35 ppm in drinking water was associated with maximum reduction in dental caries and a 10% prevalence of fluorosis.

CONCLUSIONS

Determining the most appropriate concentrations of fluoride in drinking water is crucial for communities. It is imperative that each country calculates its own optimal level of fluoride in drinking water based on the dose-response relationship of fluoride in drinking water with the levels of caries and fluorosis. Climatic conditions, dietary habits of the population and other possible fluoride exposures need to be considered in formulating these recommendations.

Vinte e quatro meses de heterocontrole da fluoretação das águas de abastecimento público de Pelotas, Rio Grande do Sul, Brasil

O objetivo deste estudo foi monitorar, mensalmente, os níveis de flúor na água de abastecimento público de Pelotas, Rio Grande do Sul, Brasil, bem como verificar a validade da formação de grupos de heterocontrole. Pelotas foi dividida em 16 pontos geográficos, incluindo as três Estações de Tratamento da água e a coleta foi feita de novembro de 1999 a outubro de 2001, em duplicata. Após a coleta, as amostras foram enviadas ao Laboratório de Vigilância Sanitária de Flúor da Universidade do Vale do Itajaí, onde a análise foi feita utilizando-se o método eletrométrico (Orion 920A/Eletrodo Orion 9609). Após 24 meses, 764 unidades amostrais foram coletadas e verificou-se uma inconstância nos resultados, predominando níveis insuficientes de flúor até o primeiro trimestre de 2001, quando houve um significativo aumento no número de unidades amostrais com uma concentração de flúor ideal (0,6-0,9ppmF), porém, há o surgimento de pontos revelando um excesso de fluoretos (> 1ppmF). Os resultados permitiram concluir que o heterocontrole é fundamental para buscar a manutenção de um correto programa de FAAP.

Determination of appropriate exposure to fluoride in non-EME countries in the future

An appropriate exposure to fluoride must be able to interfere with the development of dental caries (benefit) without great concern for dental fluorosis (risks). This condition in relation to individual seems feasible leading to a rational use of fluoride. Nevertheless, dealing with population and particularly non-EME countries (non-Established Market Economies or developing), the most suitable method of fluoride use will depend on each nation. On the other hand, each country should have a public health program to control dental caries as part of its health system. The choice between fluoridated dentifrice or fluoridated drinking water and the option for salt will depend on its applicability in each country. At the same time, it is important that either the appropriate exposure to a community method of fluoride use as well as the association with other methods and preventive measures in relation to risks-benefits are evaluated for each country. The determination of an appropriate exposure to fluoride in non-EME countries in the future will depend on critical analysis of how it has been used at present. Available data have shown that some non-EME countries have even been able to revert the dramatic situation of dental caries in their population, but in others caries experience continues a public health problem. Nevertheless, in other countries the increase in caries prevalence, which was expected, has not occurred but endemic fluorosis has been a concern. The challenges for non-EME countries are huge and identical solutions cannot be used for distinct problems.

Trends in dental caries in Latin American and Caribbean 5-6- and 11-13-year-old children: a systematic review

OBJECTIVES

To determine trends in dental caries prevalence and severity in Latin America and Caribbean.

METHODS

A systematic review was done of studies published between 1970 and 2000 among 5-6- and 11-13-year-old children that used WHO caries diagnostic criteria.

RESULTS

Over the last 30 years, there has been a significant decrease in caries severity for children 5-6 years old and also a significant decrease in caries prevalence and severity for children 11-13 years old. The same broad trends were observed when caries prevalence and severity was analyzed for the last 20 and 10 years but these were not statistically significant.

CONCLUSIONS

Evidence of a decrease in dental caries in Latin American and Caribbean children has been shown, although the decrease was less prominent in the past few years.

Fluoride concentrations in three types of commercially packed tea drinks in Taiwan

Tea is a popular drink around the world. It is also one of the major sources of fluoride intake. The objectives of this study were to assess fluoride concentrations in popular non-, semi-, and full-fermented tea drinks sold on the Taiwan market. Concentration differences among three types of commercially available tea drinks (tea leaf, tea bag, and packaged tea beverage) were explored. Several influential factors in intake concentrations were evaluated. The acute threshold intake (ATI) and allowable daily intake (ADI) of those tea drinks were also estimated. For each commercial type, samples from the most popular tea in one particular fermentation degree (non, semi, and full) were randomly purchased and analyzed for fluoride concentrations. Fluoride levels in different rounds of tea, in different containers, and with different ratios of water and tea leaf were also assessed. In total, 132 tea samples were analyzed. The mean fluoride concentrations in leaf tea without the first round, leaf tea with the first round, bagged tea, and packaged tea were 7.04, 7.79, 5.37, and 25.7 mg/l, respectively. Most of the intake concentrations in those samples exceeded 4 mg/l F, the lower bound of fluoride levels reported in the literatures to be associated with a lower IQ in children and a higher risk of bone fracture. Fluoride concentrations in packaged tea were the highest among the three types of commercially available tea. For studied leaf and bagged tea, almost a constant amount of fluoride was infused from the same amount of tea leaf regardless of the water volume. Besides this, making tea with glass or pottery tea makers would not affect fluoride intake concentrations. Acute intoxication is unlikely to occur. However, tea lovers in high fluoride content areas shall consider limit their consumption of tea drinks to avoid potential chronic effects.

Dental fluorosis in Chilean children: evaluation of risk factors

The purpose of this case-control study was to determine the association between very-mild-to-moderate enamel fluorosis and exposure during early childhood to fluoridated water, mainly through ingestion of powdered milk. Analysis was performed on 136 residents of the optimally fluoridated community of San Felipe in the Chilean Fifth Region, who were categorised into one of three groups according to their age when water fluoridation was introduced in 1986: Group I was born after 1986; Group II was 16-24 months old in 1986; and Group III was >24 months of age. The case and control subjects were selected on the basis of a clinical examination given in July 1996. Dean's scoring system was used to determine fluorosis status. Risk factor exposure was ascertained by a questionnaire used in interviews with mothers of participating children. Logistic regression analysis, after adjustment for confounding variables, revealed that very-mild-to-moderate enamel fluorosis of permanent central maxillary incisors (CMI) was strongly associated both with the age of the subjects when water fluoridation began and with breast-feeding duration for children belonging to Group I. Subjects in Group I were 20.44 times more likely (95% CI: 5.00-93.48) to develop CMI fluorosis than children who were older than 24 months (Group III) when fluoridation began. Subjects who were between 16 and 24 months old when water fluoridation began were 4.15 times more likely (95% CI: 1.05-16.43) to have CMI fluorosis than children older than 24 months. An inverse association was found with breastfeeding duration (OR=0.86, 95% CI: 0.75-0.98) among Group I subjects but not in Groups II and III. Results obtained suggest that the current fluoride concentration in drinking water may be contributing to fluorosis. Further studies will be necessary to determine the relative competing risks of dental fluorosis and dental caries in Chilean children in order to establish the most appropriate water fluoridation level in Chile.