Socio-economic status and access to fluoridated water in Queensland: an ecological data linkage study.

OBJECTIVES: To investigate the relationship between access to fluoridated drinking water and area-level socio-economic status in Queensland. STUDY DESIGN: Ecological, geospatial data linkage study. SETTING: Queensland, by statistical area level 2 (SA2), 2021. MAIN OUTCOME MEASURES: Proportion of SA2s and of residents with access to fluoridated drinking water (natural or supplemented); relationship at SA2 level between access to fluoridated water and socio-economic status (Index of Relative Socio-economic Advantage and Disadvantage, IRSAD; Index of Economic Resources, IER). RESULTS: In 2021, an estimated 4 050 168 people (79.4% of the population) and 397 SA2 regions (72.7%) in Queensland had access to fluoridated water. Access was concentrated in the southeastern corner of the state. After adjusting for SA2 population, log area, and population density, the likelihood of access to fluoridated drinking water almost doubled for each 100-rank increase in IRSAD (adjusted odds ratio [aOR], 1.93; 95% confidence interval [CI], 1.59-2.36) or IER (aOR, 1.77; 95% CI, 1.50-2.11). CONCLUSIONS: The 2012 decision to devolve responsibility for water fluoridation decisions and funding from the Queensland government to local councils means that residents in lower socio-economic areas are less likely to have access to fluoridated water than those in more advantaged areas, exacerbating their already greater risk of dental disease. Queensland water fluoridation policy should be revised so that all residents can benefit from this evidence-based public health intervention for reducing the prevalence of dental caries.

Effects of water fluoridation on early embryonic development of zebrafish.

Fluoride has strong electronegativity and exposes diversely in nature. Water fluoridation is the most pervasive form of occurrence, representing a significant threat to human health. In this study, we investigate the morphometric and physiological alterations triggered by fluoride stimulation during the embryogenesis of zebrafish and reveal its putative effects of stage- and/or dose-dependent. Fluoride exhibits potent biological activity and can be extensively absorbed by the yolk sac, exerting significant effects on the development of multiple organs. This is primarily manifested as restricted nutrient utilization and elevated levels of lipid peroxidation, further leading to the accumulation of superoxide in the yolk sac, liver, and intestines. Moreover, pericardial edema exerts pressure on the brain and eye development, resulting in spinal curvature and reduced body length. Besides, acute fluoride exposure with varying concentrations has led to diverse teratogenic outcomes. A low dose of water fluoridation tends to induce abnormal development of the embryonic yolk sac, while vascular malformation is widely observed in all fluoride-treated groups. The effect of fluoride exposure on blood circulation is universally present, even in zebrafish larvae that do not exhibit obvious deformities. Their swimming behavior is also affected by water fluoridation, resulting in reduced activity and delayed reactions. In conclusion, this study provides valuable insights into the monitoring of environmental quality related to water fluoridation and disease prevention.

A quality appraisal of economic evaluations of community water fluoridation: A systematic review.

OBJECTIVES: To critically appraise the methodological conduct and reporting quality of economic evaluations (EE) of community water fluoridation (CWF). METHODS: A systematic literature search was conducted in general databases and specialist directories of the economic literature. The Consensus on Health Economic Criteria list (CHEC) appraised the methodological quality while the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) assessed the reporting quality of included studies. RESULTS: A total of 1,138 records were identified, of which 18 met the inclusion criteria. Cost analysis emerged as the most prevalent type of EE, though a growing trend towards conducting full EEs is observed. CHEC revealed the items most frequently unfulfilled were the study design, measurement and valuation of costs and outcomes, while CHEERS also identified reporting deficiencies in these aspects. Furthermore, the review highlights subtleties in methodological aspects that may not be discerned by CHEC, such as the estimation of the impact of fluoridation and the inclusion of treatment savings within cost estimates. CONCLUSIONS: While numerous studies were conducted before publication of these assessment instruments, this review reveals that a noteworthy subset of studies exhibited good methodological conduct and reporting quality. There has been a steady improvement in the methodological and reporting quality over time, with recently published EEs largely adhering to best practice guidelines. The evidence presented will assist policymakers in leveraging the available evidence effectively to inform resource allocation decisions. It may also serve as a resource for researchers to enhance the methodological and reporting standards of future EEs of CWF.

The fluorosis conundrum: bridging the gap between science and public health.

Fluorosis, a chronic condition brought on by excessive fluoride ingestion which, has drawn much scientific attention and public health concern. It is a complex and multifaceted issue that affects millions of people worldwide. Despite decades of scientific research elucidating the causes, mechanisms, and prevention strategies for fluorosis, there remains a significant gap between scientific understanding and public health implementation. While the scientific community has made significant strides in understanding the etiology and prevention of fluorosis, effectively translating this knowledge into public health policies and practices remains challenging. This review explores the gap between scientific research on fluorosis and its practical implementation in public health initiatives. It suggests developing evidence-based guidelines for fluoride exposure and recommends comprehensive educational campaigns targeting the public and healthcare providers. Furthermore, it emphasizes the need for further research to fill the existing knowledge gaps and promote evidence-based decision-making. By fostering collaboration, communication, and evidence-based practices, policymakers, healthcare professionals, and the public can work together to implement preventive measures and mitigate the burden of fluorosis on affected communities. This review highlighted several vital strategies to bridge the gap between science and public health in the context of fluorosis. It emphasizes the importance of translating scientific evidence into actionable guidelines, raising public awareness about fluoride consumption, and promoting preventive measures at individual and community levels.

Water fluoridation between public health and public law: an assessment of regulations across countries and their preventive medicine implications.

Background: Among health professionals and health policymakers concern is growing as to the difficulty of balancing the prevention of dental caries through cost-effective interventions and the need to limit unnecessary exposure of the population, and especially children, to environmental chemicals. In this respect, the use of water fluoridation to prevent tooth decay epitomizes the dilemma by raising questions relevant to both public health and public law, ranging from the balance of public health and medical self-determination, the division of powers between local or national authorities over water fluoridation, and the need to avoid the adverse effects of socioeconomic inequalities as well as both under- and over-exposure. Study design: We carried out a narrative review by searching the relevant literature about the laws and rules related to drinking water fluoridation at the community level in the US, UK, and Europe, in order to discuss how the issue is handled from both a public health and public law perspective. Methods: Sources of data for this review were the biomedical and legal literature retrieved by searching online databases, and websites of public health and legal institutions. Results and Conclusions: We found that water fluoridation is still largely adopted throughout the US, while in the UK and particularly in the European Union only a minor part of the population is subject to it. In addition, the recommended and maximum allowed amounts of fluoride in drinking water are being adapted to the public health recommendations and the new regulations, within an evolving evaluation of the epidemiologic evidence and the risk assessment currently in progress by two major regulatory agencies, the US National Toxicology Program - NTP and the European Food Safety Authority - EFSA. Under a comparative public law perspective, the three investigated legislations are facing a reassessment of their policies and regulations, to allow for effective and safe public health measures in the field of water fluoridation and more generally for a preferred use of topical fluoride for caries prevention. A consistent trend across these legislations is the choice to centralize at the national level regulatory and management issues related to water fluoridation, and to carefully balance benefits for dental caries prevention in children and the potential risks of systemic overexposure associated with excess fluoride intake, by promptly responding to the evolving indications by the scientific community and the public health professionals.

Fluoride and children's IQ: evidence of causation lacking.

DATA SOURCES: Human, animal, and in vitro studies. Extensive literature search of multiple bibliographic databases, trial registries, major grey literature sources and bibliographies of identified studies. STUDY SELECTION: The authors aimed to identify studies which could be used to determine the maximum safe level for fluoride in drinking water. To identify new studies published since a 2016 Australian review, the search period was 2016 to July 2021. Studies which evaluated the association between either naturally or artificially fluoridated water (any concentration) and any health outcomes were included. No restrictions on study design or publication status. Articles published in a 'non-Latin language' were excluded. Screening of abstracts and full texts was in duplicate. For IQ and dental fluorosis, a top-up search was conducted between 2021 and Feb 2023. DATA EXTRACTION AND SYNTHESIS: Extensive data extraction. Risk of bias assessment using the OHAT tool. A narrative synthesis of the results was carried out. RESULTS: The review included 89 studies in humans, 199 in animals and 10 reviews of in vitro studies. Where there was consistent evidence of a positive association, in relation to a water fluoride concentration of <20 ppm (mg F/L), and where studies were judged to be acceptable or high quality, health effects were taken forwards for further examination of causality using Bradford Hill's 9 criteria. Of the 39 health outcomes reviewed, 4 were further assessed for causality. The authors reported 'strong' evidence of causality for dental fluorosis and reductions in children's IQ scores, 'moderate' strength evidence for thyroid dysfunction, 'weak' for kidney dysfunction, and 'limited' evidence for sex hormone disruption. CONCLUSIONS: The authors conclude that moderate dental fluorosis and reductions in children's IQ scores are the most appropriate health outcomes to use when setting an upper safe level of fluoride in drinking water. For reductions in children's IQ, the authors acknowledge a biological mechanism of action has not been elucidated, and the dose response curve is not clear at lower concentrations, limiting the ability to set an upper safe threshold.

Fishing for the evidence on community water fluoridation: a commentary on the CATFISH study.

DATA SOURCE: Goodwin M, Emsley R, Kelly M P et al. Evaluation of water fluoridation scheme in Cumbria: the CATFISH prospective longitudinal cohort study. Southampton: National Institute for Health and Care Research, 2022. METHODS: This longitudinal, prospective cohort study, recruited two populations - a birth cohort and older school cohort - assessing the effects of community water fluoridation (CWF) over a five-year period. The control group received non-fluoridated drinking water in the East of Cumbria, while the intervention group received fluoridated drinking water in the West of Cumbria. The primary outcome measures were the presence or absence of decay into dentine in primary and permanent teeth. Cost effectiveness was assessed by quality-adjusted life-years. RESULTS: Birth Cohort: Modest beneficial effect (17.4% with decay, 21.4% in control). Adjusted Odd Ratios (AOR): 0.74 (95% CI: 0.56 to 0.98). Older Cohort: Insufficient evidence of difference (19.1% with decay and 21.9% in control). AOR: 0.80 (95% CI: 0.58 to 1.09). CONCLUSION: The authors concluded that CWF was effective in the birth cohort and that the modest absolute reduction in caries should be considered in the context of other preventive measures. A longer follow-up period was recommended to fully understand the benefits and risks of CWF in contemporary low-prevalence populations.

Community Water Fluoridation Levels To Promote Effectiveness and Safety in Oral Health - United States, 2016-2021.

Drinking water fluoridated at the level recommended by the U.S. Public Health Service (USPHS) reduces dental caries (cavities) by approximately 25% in children and adults (1). USPHS recommends fluoride levels to achieve oral health benefits and minimize risks associated with excess fluoride exposure. To provide the benefits of community water fluoridation, water systems should target a level of 0.7 mg/L and maintain levels ≥0.6 mg/L (2). The Environmental Protection Agency (EPA) sets a safety standard at 2.0 mg/L to prevent mild or moderate dental fluorosis, a condition that causes changes in the appearance of tooth enamel caused by hypermineralization resulting from excess fluoride intake during tooth-forming years (i.e., before age 8 years). During 2016-2021, fluoride measurements for 16.3% of population-weighted monthly fluoride measurements (person-months) reported by community water systems to CDC's Water Fluoridation Reporting System (WFRS) were <0.6 mg/L; only 0.01% of person-months exceeded 2.0 mg/L. More than 80% of population-weighted fluoride measurements from community water systems reporting to WFRS were above 0.6 mg/L. Although 0.7 mg/L is the recommended optimal level, ≥0.6 mg/L is still effective for the prevention of caries. A total of 4,080 community water systems safely fluoridated water 99.99% of the time with levels below the secondary safety standard of 2.0 mg/L. Water systems are encouraged to work with their state programs to report their fluoride data into WFRS and meet USPHS recommendations to provide the full benefit of fluoridation for caries prevention.

The effect of community water fluoridation on dental caries in children and young people in England: an ecological study.

BACKGROUND: The protective effect of community water fluoridation (CWF) against dental caries may be modified by secular changes in health behaviour. We aimed to determine the contemporary association between fluoride in public water supplies (PWS) and dental caries indicators and inequalities in England. METHODS: We estimated exposure to CWF and PWS fluoride concentrations from national monitoring data, using Geographic Information Systems and water supply boundaries, categorizing mean period exposure into <0.1, 0.1-<0.2, 0.2-<0.4, 0.4-<0.7 and ≥0.7 mg/l. We used area-level health outcome and confounder data in multivariable regression models to determine the association between fluoride and caries outcomes and calculated preventive fractions using these coefficients. RESULTS: The odds of caries and of severe caries in 5-year-olds fell with increasing fluoride concentration in all SES quintiles (P < 0.001 to P = 0.003). There was a negative trend between increasing fluoride concentration and dental extractions (P < 0.001). Compared to PWS with <0.2 mg/l, CWF prevented 17% (95% confidence interval (CI): 5-27%) to 28% (95% CI: 24-32%) of caries (high-low SES) and 56% (95% CI: 25-74%) of dental extractions. The association between fluoride concentration and caries prevalence/severity varied by socioeconomic status (SES) (P < 0.001). CONCLUSIONS: Exposure to fluoride in PWS appears highly protective against dental caries and reduces oral health inequalities.

Risk Communication in Public Health: Lessons from a Historic Fluoridation Debate in Saskatchewan.

Effective risk communication is critical to gain public support when implementing population-level health interventions. Analysis of previous public health campaigns can provide guidance for future efforts. This case study examined a successful community water fluoridation campaign in Saskatoon, Canada, during 1953/54. The key strategies and messaging used by both sides of the debate were assessed using two publicly available historic data sources: documents in the city archives and newspaper coverage. The anti-fluoridation campaign approaches (e.g. misinformation, innuendo, half-truths and scare words, requesting a plebescite) were similar to those used elsewhere by this movement as described in the literature. Key features of the effective pro-fluoridation campaign included extensive community outreach, involvement of local experts, dissemination of supporting evidence while aggressively addressing misinformation, highlighting the support of relevant health organizations, and ensuring key messages received media coverage. This study illustrates how misinformation and public opposition has posed a challenge to public health efforts long before the advent of social media and highlights strategies, consistent with current risk communication principles, that have stood the test of time.

Association between low fluoride exposure and children's intelligence: a meta-analysis relevant to community water fluoridation.

OBJECTIVES: Previous meta-analyses have mainly focused on studies conducted in endemic fluorosis areas with relatively high fluoride concentrations. These are impoverished rural communities in China, India, and Iran, and the findings cannot be generalised to developed countries. Therefore, we investigated the association between fluoride concentrations relevant to community water fluoridation and children's cognition measured with IQ scores by synthesising effect sizes reported in observational studies. METHODS: A previous meta-analysis and the National Toxicology Program database that included a search of multiple databases and the authors' search of PubMed, Google Scholar, and Mendeley provided the data. Cross-sectional and cohort studies examining the association between fluoride and children's cognition and intelligence scores were selected. Two reviewers abstracted data using standard procedures. We performed three meta-analyses to synthesise the effects using the random effects models. RESULTS: Eight studies of standardized mean difference in IQ scores from non-endemic fluorosis areas found no statistically significant difference between recommended and lower levels of fluoride (standardized mean difference = 0.07; 95% confidence interval: -0.02, 0.17; I2 = 0%), and no significant fluctuation in IQ scores across the differences in fluoride concentrations by non-linear modeling with restricted cubic spline (P = 0.21). Meta-analyses of children's and maternal spot urinary fluoride associated pooled regression coefficients (Betachildren = 0.16; 95% confidence interval: -0.40, 0.73; P = 0.57; I2 = 0%, Betamaternal = -0.92; 95% CI: -3.29, 1.46; P = 0.45; I2 = 72%) were not statistically significant. Further regression analysis by standardizing absolute mean IQ scores from lower fluoride areas did not show a relationship between F concentration and IQ scores (Model Likelihood-ratio test: P-value = 0.34.) CONCLUSIONS: These meta-analyses show that fluoride exposure relevant to community water fluoridation is not associated with lower IQ scores in children. However, the reported association observed at higher fluoride levels in endemic areas requires further investigation.

Mini-publics in dental public health policymaking.

What are mini-publics and under what circumstances could they be applied to public health dentistry? This question is explored with reference to water fluoridation in England, a policy intervention characterised by a visceral politics that has embedded a systemic preference for non-decision-making. Mini-publics can nevertheless inform decision-making by inviting a representative sample of the affected citizenry to consider the available evidence and come to a set of conclusions and/or recommendations that if all parties cannot agree, none can reasonably object. In doing so, mini-publics have the potential to break the policy deadlock by adding an additional layer of legitimacy to the decision-making process, albeit this is dependent upon decision-makers granting value to their findings.

Quantifying Fluoridation Exposure Over Time in Alberta, Canada: Challenges and Implications for Dental Public Health Surveillance.

BACKGROUND: Community water fluoridation is one component of a multifactorial approach to preventing dental caries. Yet, fluoridation monitoring in Canada has historically been fragmented, and recent national estimates give little indication of trends at the provincial or municipal levels. We aimed to quantify fluoridation exposure trends in Alberta from 1950 to 2018 at both the population and municipal levels. Insights have implications for dental public health surveillance. METHODS: Drawing from various public sources, we compiled a list of all Alberta municipalities, noting type of municipality and annual population count from 1950 to 2018. We recorded fluoridation status (excluding naturally occurring fluoride) by year for each municipality, based on the start and end (if ever) dates. We calculated annual fluoridation exposure at the population level (% of Alberta population exposed) and the municipality level (number of municipalities exposed) to visually assess trends over time. RESULTS: Population exposure to fluoridation in Alberta generally increased from 1950 to 2010. A sharp drop occurred in 2011, after which exposure fluctuated at around 43-45%. Municipality exposure generally increased from 1958 to 2006 and from 2012 to 2018, except for small declines during 2007-2008 and 2010-2011. Challenges concerning data completeness were considerable. CONCLUSION: Our findings illuminate the substantial variation in fluoridation exposure of Albertans over time, and they elucidate the complexities of estimating such exposure. They speak to the value of centralized fluoridation monitoring mechanisms as a key part of dental public health surveillance infrastructure.

Access to community water fluoridation in rural Victoria: It depends where you live .

OBJECTIVE: To explore the water fluoridation status of rural Victorian towns over 1000 population and document the oral health profile in the local government areas (LGAs) currently with no water fluoridation. To assist/inform future LGA planning, we describe a case study of a community-based co-design approach to increase access to fluoridated water in rural communities. DESIGN: A descriptive design and a case study. SETTING: Rural Victorian towns over 1000 population. PARTICIPANTS: Twenty-nine LGAs in rural areas. MAIN OUTCOME MEASURE(S): LGA water fluoridation status and oral health profiles. RESULTS: Sixty-six (33%) of the 203 Victorian rural towns with >1000 population, representing 149 251 people, did not have access to fluoridated water. Towns in 29 rural LGAs were included with 62% without water fluoridation with many having higher than the Victorian average of preventable hospital admissions due to dental conditions in children aged 0-9 years. Over 50% of children aged 0-12 years living in these rural nonfluoridated LGAs had above-the-state average rates of decayed, missing and filled teeth (dmft/DMFT). In those aged 0-5 years, this was the highest with 78% above-the-state average. In the case study, meetings were well attended, and the group resolved to lobby for water fluoridation, which was successful. CONCLUSION: Many Victorian rural towns do not have access to fluoridated water. A community-based co-design approach can dispel ill-informed concerns about dangers of water fluoridation to successfully lobby the state government to fluoridate the local water supply.

Costs and benefits of community water fluoridation in remote Aboriginal communities of the Northern Territory.

OBJECTIVE: To undertake an economic evaluation of community water fluoridation (CWF) in remote communities of the Northern Territory (NT). DESIGN: Dental caries experiences were compared between CWF and non-CWF communities before and after intervention. Costs and benefits of CWF are ascertained from the health sector perspective using water quality, accounting, oral health, dental care and hospitalisation datasets. SETTING AND PARTICIPANTS: Remote Aboriginal population in the NT between 1 January 2008 and 31 December 2020. INTERVENTION: CWF. MAIN OUTCOME MEASURES: Potential economic benefits were estimated by changes in caries scores valued at the NT average dental service costs. RESULTS: Given the total 20-year life span of a fluoridation plant ($1.77 million), the net present benefit of introducing CWF in a typical community of 300-499 population was $3.79 million. For each $1 invested in CWF by government, the estimated long-term economic value of savings to health services ranged from $1.1 (population ≤300) to $16 (population ≥2000) due to reductions in treating dental caries and associated hospitalisations. The payback period ranged from 15 years (population ≤300) to 2.2 years (population ≥2000). CONCLUSIONS: The economic benefits of expanding CWF in remote Aboriginal communities of NT outweigh the costs of installation, operation and maintenance of fluoridation plants over the lifespan of CWF infrastructure for population of 300 or more.

Role of renal function in the association of drinking water fluoride and plasma fluoride among adolescents in the United States: NHANES, 2013-2016.

CONTEXT: While fluoride has been added to drinking water and dental products for decades in order to prevent tooth decay, there are growing concerns about its potential toxicity. Given that fluoride is primarily excreted in urine, an important question that has not been examined is whether among those whose drinking water is fluoridated, impaired renal function is associated with higher levels of circulating fluoride. OBJECTIVE: To examine the association between drinking water and plasma fluoride and its modification by renal function. DESIGN, SETTING, AND PARTICIPANTS: Participants in the National Health and Nutrition Examination Survey (NHANES) between 2013 and 2016 with measures of fluoride in plasma and drinking water and renal function. These measures were only available in adolescent age 12-19 years. OUTCOMES: Plasma fluoride levels and their modification by strata of renal function, measured by the estimated glomerular filtration rate (eGFR). RESULTS: Among 1841 healthy adolescents, a 10 ml/min/1.73 m (Penman et al., 1997) lower eGFR and a 1 mg/L higher drinking water fluoride concentration were associated with a 0.02 (95%CI -0.02, -0.03) umol/L and 0.23 (95%CI 0.15,0.30) umol/L higher adjusted plasma fluoride level, respectively. The association of water and plasma fluoride levels was most robust among those with lower renal function (multiplicative interaction p value < 0.001). For adolescents in the lowest eGFR quartile, a 1 mg/L higher drinking water fluoride concentration was associated with a 0.35 (95%CI 0.21,0.48) umol/L higher plasma fluoride level, compared to 0.20 (95%CI 0.14,0.26) umol/L in the highest eGFR quartile. Restriction to those with measurable plasma fluoride levels yielded similar results. CONCLUSIONS: Water fluoridation results in higher plasma fluoride levels in those with lower renal function. How routine water fluoridation may affect the many millions of Americans with Chronic Kidney Disease, who are particularly susceptible to heavy metal and mineral accumulation, needs to be further investigated.

Water fluoride concentrations in England, 2009-2020.

OBJECTIVES: Contemporary research, surveillance and monitoring of water fluoridation requires an understanding of the population coverage of this intervention. The aims of this research are to create the first publicly available record of water fluoride concentrations in England and to describe and visualise the observed variation in water fluoride concentrations and optimal fluoridation (⟩/= 0.7 mg F/L) between 2009-2020. BASIC RESEARCH DESIGN: Routine water quality sampling data were requested from water companies in England from 2009-2020 under the provisions of the Environmental Information Regulations 2004. Fluoride concentrations of Water Supply Zones (WSZs) were assigned to Lower Super Output Areas (LSOAs) using population-weighted centroids. RESULTS: Between 2009-2020 4247 LSOAs (12.9%) had an annual mean water fluoride concentration of ⟩/= 0.7 mg F/L in at least one year, and 3019 LSOAs (9.1%) had a grand mean fluoride concentration of ⟩/= 0.7 mg F/L. Coverage of optimal fluoridation varied over time; from 10.9% of LSOAs in 2014 to 6.3% in 2016. DISCUSSION: This study confirms previous work identifying variability in the coverage and achieved concentrations of water fluoridation programmes. The current provision for accessing, collating and utilising these data are a barrier to essential monitoring, surveillance and research. An annually maintained and publicly accessible database of water fluoride concentrations is urgently required.

Who are the 10%? Characteristics of the populations and communities receiving fluoridated water in England.

OBJECTIVES: In England, around 10% of the population receive optimally fluoridated water. This coverage has evolved through a combination of historical local decision-making and natural geography, rather than being strategically targeted at the national level. It is important to understand if the current distribution is equitable according to indicators of oral health need and to identify any population-level differences in socio-demographic characteristics that could introduce bias to studies evaluating the effectiveness of water fluoridation. BASIC RESEARCH DESIGN: Descriptive analysis comparing the census characteristics of populations that received optimally fluoridated (=/⟩ 0.7 mg F/L) and non-fluoridated water (⟨0.7 mg F/L) between 2009 and 2020. RESULTS: Populations receiving fluoridated water between 2009-2020 were on average slightly younger, more urban, more deprived, with lower education levels, higher unemployment and lower car and home ownership than the populations who received non-fluoridated water. They are more ethnically diverse, with a higher proportion of Asian ethnicity and a lower proportion of White ethnicity, compared to the non-fluoridated population. DISCUSSION: This descriptive analysis provides evidence that water fluoridation coverage within England is targeted reasonably equitably in relation to population-level indicators of need. It also confirms the need to consider the impact of underlying differences in age, deprivation, rurality, and ethnicity when evaluating the impact of water fluoridation on health outcomes in England.

Effectiveness of water fluoridation in an upper-middle-income country: A systematic review and meta-analysis.

AIM: To summarize the information on the effectiveness of community water fluoridation (CWF) on the reduction of dental caries in the context of the wide use of fluoridated toothpaste in Brazil. DESIGN: A systematic review was conducted regarding the effect of CWF based on studies with Brazilian population groups using the following electronic databases: MEDLINE/PubMed, LILACS, SciELO, and SCOPUS. The literature search was conducted up to August 2019. Studies that compared caries experience in at least two areas, one fluoridated and the other non-fluoridated, by mean dmft/DMFT (decayed, missing, and filled teeth) index or caries prevalence (caries vs. caries-free) were included. Considering the beginning of widespread use of fluoride dentifrice and the time for producing dental caries decline, studies published before 1995 were excluded. Descriptive analysis and meta-analyses were carried out. The effect size was measured by mean difference for dmft and DMFT ± SD and odds ratios on a logarithmic scale for caries prevalence. RESULTS: Of the 574 studies retrieved, 16 and 10 were included in the qualitative and quantitative analysis, respectively. Fluoridated areas exhibited lower mean dmft/DMFT than non-fluoridated areas did. The mean difference in the dmft between non-fluoridated and fluoridated areas was -2.28 (95% CI -3.26; -1.30) for children aged 5-8 years and -1.12 (95% CI -1.93; -0.32) for those aged 3-12 years; the mean difference in the DMFT was -0.61 (95% CI -0.80; -0.42) for the children aged between 7 and 12 years. The caries prevalence was 1.4 times and 57% lower, respectively, at primary and permanent dentition in fluoridated areas. Heterogeneity was observed in all age groups, ranging from 77.6% to 98.2%. CONCLUSION: Community water fluoridation remains effective in preventing dental caries in children younger than 13 years, even with the widespread use of fluoridated toothpaste.

Physical properties of root cementum: Part 28. Effects of high and low water fluoridation on orthodontic root resorption: A microcomputed tomography study.

INTRODUCTION: Transient inflammatory surface resorption, referred to as orthodontic induced inflammatory root resorption (OIIRR), is an iatrogenic consequence of orthodontic tooth movement. Systemic fluoride has been associated with a reduction of OIIRR. This study aimed to investigate the effects of water fluoridation levels on OIIRR in a clinically applicable human orthodontic model. METHODS: Twenty-eight patients who required bilateral maxillary first premolar extraction as part of orthodontic treatment were selected from 2 cities with high and low water fluoridation of ≥2 ppm and ≤0.05 ppm, respectively. Patients were separated into high fluoride (HF) and low fluoride (LF) groups on the basis of water fluoridation levels. Bilateral maxillary first premolar teeth were subjected to 150 g of buccal tipping forces for 12 weeks with reactivation every 4 weeks. Teeth were extracted at the end of 12 weeks. Root resorption crater volume was determined using microcomputed tomography and 3-dimensional reconstruction. RESULTS: HF group showed significantly less mean root resorption volume on the palatal root surface when compared with the LF group (P = 0.025). This difference was specifically displayed at palatal apical regions (P = 0.041). When root resorption volumes from the zones of orthodontic pressure (buccal cervical, palatal apical) were combined, the mean difference between HF and LF groups was statistically significant (P = 0.045). CONCLUSIONS: Findings of the present study indicated a positive correlation between water fluoridation and the reduction of OIIRR, especially at the zones of orthodontic pressure, using a clinically relevant human orthodontic model.