Consequences of community water fluoridation cessation for Medicaid-eligible children and adolescents in Juneau, Alaska

Effect of fluoridated water on invasive NHS dental treatments for adults: the LOTUS retrospective cohort study and economic evaluation

Background

Most water fluoridation studies were conducted on children before the widespread introduction of fluoride toothpastes. There is a lack of evidence that can be applied to contemporary populations, particularly adolescents and adults.

Objective

To pragmatically assess the clinical and cost effectiveness of water fluoridation for preventing dental treatment and improving oral health in a contemporary population of adults, using a natural experiment design.

Design

Retrospective cohort study using routinely collected National Health Service dental claims (FP17) data.

Setting

National Health Service primary dental care: general dental practices, prisons, community dental services, domiciliary settings, urgent/out-of-hours and specialised referral-only services.

Participants

Dental patients aged 12 years and over living in England (n = 6,370,280).

Intervention and comparison

Individuals exposed to drinking water with a fluoride concentration ≥ 0.7 mg F/l between 2010 and 2020 were matched to non-exposed individuals on key characteristics using propensity scores.

Outcome measures

Primary: number of National Health Service invasive dental treatments (restorations/'fillings' and extractions) received per person between 2010 and 2020. Secondary: decayed, missing and filled teeth, missing teeth, inequalities, cost effectiveness and return on investment.

Data sources

National Health Service Business Services Authority dental claims data. Water quality monitoring data.

Primary outcome

Predicted mean number of invasive dental treatments was 3% lower in the optimally fluoridated group than in the sub/non-optimally fluoridated group (incidence rate ratio 0.969, 95% CI 0.967 to 0.971), a difference of -0.173 invasive dental treatments (95% CI -0.185 to -0.161). This magnitude of effect is smaller than what most stakeholders we engaged with (n = 50/54) considered meaningful.

Secondary outcomes

Mean decayed, missing and filled teeth were 2% lower in the optimally fluoridated group, with a difference of -0.212 decayed, missing and filled teeth (95% CI -0.229 to -0.194). There was no statistically significant difference in the mean number of missing teeth per person (0.006, 95% CI -0.008 to 0.021). There was no compelling evidence that water fluoridation reduced social inequalities in treatments received or missing teeth; however, decayed, missing and filled teeth data did not demonstrate a typical inequalities gradient. Optimal water fluoridation in England in 2010-20 was estimated to cost £10.30 per person (excluding original setup costs). Mean National Health Service treatment costs for fluoridated patients 2010-20 were 5.5% lower per person, by £22.26 (95% CI -£23.09 to -£21.43), and patients paid £7.64 less in National Health Service dental charges per person (2020 prices).

Limitations

Pragmatic, observational study with potential for non-differential errors of misclassification in fluoridation assignment and outcome measurement and residual and/or unmeasured confounding. Decayed, missing and filled teeth data have not been validated. Water fluoridation cost estimates are based on existing programmes between 2010 and 2020, and therefore do not include the potentially significant capital investment required for new programmes.

Conclusions

Receipt of optimal water fluoridation between 2010 and 2020 resulted in very small health effects, which may not be meaningful for individuals, and we could find no evidence of a reduction in social inequalities. Existing water fluoridation programmes in England produced a positive return on investment between 2010 and 2020 due to slightly lower National Health Service treatment costs. These relatively small savings should be evaluated against the projected costs and lifespan of any proposed capital investment in water fluoridation, including new programmes.

Future work

National Health Service dental data are a valuable resource for research. Further validation and measures to improve quality and completeness are warranted.

Trial registrations

This trial is registered as ISRCTN96479279, CAG: 20/CAG/0072, IRAS: 20/NE/0144.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR award ref: NIHR128533) and is published in full in Public Health Research; Vol. 12, No. 5. See the NIHR Funding and Awards website for further award information.

Community water fluoride cessation and rate of caries-related pediatric dental treatments under general anesthesia in Alberta, Canada

OBJECTIVE

This study examined the rate of caries-related dental treatments under general anesthesia (GA) in fluoridated and non-fluoridated communities in Alberta, Canada, between 2010 and 2019.

METHODS

This retrospective, population-based study included all children ( < 12 years of age) living in Calgary (non-fluoridated) and Edmonton (fluoridated) who underwent caries-related dental treatments under GA at publicly funded facilities. Demographics and dental data were extracted from health administrative databases for three time periods of 2010/11 (pre-cessation), 2014/15, and 2018/19 (post-cessation).

RESULTS

Among 2659 children receiving caries-related treatments under GA, the mean (SD) and median (IQR) age were 4.8 (2.3) and 4 (3-6) years, respectively, and 65% resided in the non-fluoridated area. The analysis revealed that the cessation of water fluoridation was significantly associated with an increased rate of caries-related GA events per 10,000 children in both age groups (0-5 and 6-11 years), with a more pronounced effect in 0-5-year-olds in non-fluoridated areas. The risk of dental treatments under GA was also positively associated with post-cessation time.

CONCLUSION

Discontinuing water fluoridation appears to negatively affect young children's oral health, potentially leading to a significant increase in caries-related dental treatments under GA and oral health disparities in this pediatric population.

Community Water Fluoridation in Focus: A Comprehensive Look at Fluoridation Levels across America

Objective: This study reports on the number and percentage of community water systems (CWSs) meeting fluoride concentration standards set by the U.S. Department of Health and Human Services (DHHS). The study also explored changes in the population exposed to optimally fluoridated water in these systems between 2006 and 2020. Methods: This study analyzed U.S. Centers for Disease Control and Prevention data from 2006 to 2020, tabulating state-specific CWS fluoridation rates, ranking them, and calculating the percent change. Results: In 2020, 72.7% of the US population received CWS water, with 62.9% of those individuals served by a CWS system meeting DHHS fluoridation standards. This compares to 69.2% receiving CWS water in 2006 and 74.6% in 2012. The overall change in those receiving fluoridated water was 1.4%, from 61.5% in 2006 to 62.9% in 2020. State-specific percentages ranged from 8.5% in Hawaii to 100% in Washington DC in 2020 (median: 76.4%). Conclusions: Although endorsed by the American Dental Association, the percentage of individuals receiving fluoridated water did not increase substantially from 2006 to 2020, indicating that there has not been much progress toward meeting the Healthy People 2030 goal that 77.1% of Americans receive water with enough fluoride to prevent tooth decay.

Evaluation of the impact of fluoride in drinking water and tea on the enamel of deciduous and permanent teeth

BACKGROUND

Systemic fluoride intake is predominantly derived from drinking water and tea. It's been noted that water and tea containing fluoride, within the boundaries set by the World Health Organization, can lessen the prevalence of dental caries. A review of the literature did not uncover any study that has examined the impact of fluoride in bottled drinking water and tea on enamel of deciduous and permanent teeth. Thus, we assessed the effects of fluoride present in seven different brands of bottled water from distinct geographical regions of Turkey, and a type of tea produced and packaged in Turkey, on the enamel of deciduous and permanent teeth.

MATERIALS AND METHODS

Fluoride analysis was performed on drinking water sourced from seven different regions of Turkey and a brand of tea brewed with these waters. The tea was harvested and packaged in Turkey. The analysis was conducted using an ion-selective electrode. In total, 112 tooth enamel samples (56 deciduous molars and 56 permanent molars) were randomly divided into eight distinct groups. These were kept in water for 15 min and tea for 15 min every day for a month. The eighth group was treated with fluoride gel prior to tea and water applications. The amount of fluoride in the tooth enamel structure was evaluated using an SEM EDX device before and after the experiment.

RESULTS

Statistically significant differences were found in fluoride content of enamel between water brands and tooth type (deciduous and permanent teeth). Fluoride levels were higher in the enamel of deciduous teeth than in permanent teeth.

CONCLUSION

Regular exposure of enamel samples to black tea and water led to an increase in fluoride levels in the enamel; thus, regular consumption of black tea and fluoride water could help reduce the prevalence of dental caries.

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.

Fluoridation cessation and oral health equity: a 7-year post-cessation study of Grade 2 schoolchildren in Alberta, Canada

OBJECTIVE

Community water fluoridation, because of its universal scope and passive mechanism of uptake, is one component of a multifaceted approach to promoting equity in dental health. The objective of this study was to examine social inequities in children's dental health in the Canadian cities of Calgary (fluoridation cessation in 2011) and Edmonton (still fluoridated).

METHODS

We analyzed data from surveys of population-based samples of Grade 2 (approx. age 7) children in Calgary in 2009/2010 (pre-cessation; n=557) and in both Calgary and Edmonton in 2013/2014 (Calgary, n=3230; Edmonton, n=2304) and 2018/2019 (Calgary, n=2649; Edmonton, n=2600) (post-cessation). We estimated associations between several socioeconomic indicators and dental caries indicators (i.e., dental caries experience [deft, DMFT] and untreated decay in two or more teeth [untreated decay]) using zero-inflated Poisson, binary logistic regression, and the concentration index of inequality. We compared those associations over time (between survey waves) and between cities at post-cessation.

RESULTS

Persistent social inequities in deft and untreated decay were evident; for example, having no dental insurance was significantly associated with higher odds of untreated decay across city and survey wave. In most (but not all) cases, differences between cities and survey waves were consistent with an adverse effect of fluoridation cessation on dental health inequities. For example, the association between no dental insurance and higher odds of untreated decay in Calgary was greater in 2018/2019 (later post-cessation) than in 2009/2010 (pre-cessation; odds ratio [OR] for comparison of coefficients = 1.89 [1.36-2.63], p<0.001) and 2013/2014 (early post-cessation; OR for comparison of coefficients = 1.67 [1.22-2.28], p=0.001); that same association in 2018/2019 was greater in Calgary (fluoridation cessation) than in Edmonton (still fluoridated) (OR for comparison of coefficients = 1.44 [1.03-2.02], p=0.033).

CONCLUSION

Social inequities in dental caries were present in both Calgary and Edmonton. Those inequities tended to be worse in Calgary where fluoridation was ceased. Our findings may be relevant to other settings where income inequality is high, dental services are costly, and dental public health infrastructure is limited.

The Impact of Water Fluoridation on Medicaid-Eligible Children and Adolescents in Alaska

Juneau, Alaska, ceased community water fluoridation (CWF) in 2007, and previous research found a substantial increase in dental caries-related procedures and treatment costs for children from low-income families in Juneau between 2003 and 2012. We collected comparable dental caries-related procedures and treatment cost data for the same years for children in Anchorage, Alaska, where CWF has been continuously maintained. This retrospective study analyzed all Medicaid dental claims records in two separate years for caries-related procedures and associated costs among children (aged 0 to 18 years) residing in Anchorage's 99502 zip code and compared these records to data from Juneau. We obtained descriptive statistics and conducted bivariate analyses and binomial logistic regression. Between 2003 and 2012, children in Anchorage experienced a nonsignificant modest decrease in the mean number of caries-related procedures and only small, statistically nonsignificant changes to the mean inflation-adjusted service costs of caries-related restorative care. The lack of significant change in child dental caries-related procedures and treatment costs in Anchorage between 2003 and 2012 contrasted with the substantial increase in caries-related procedures and treatment costs over the same period in Juneau. Our results are consistent with previous research that has demonstrated a significant protective effect of CWF against dental caries.

The effect of community water fluoridation cessation on children's dental health: a national experience

BACKGROUND

Community water fluoride (CWF) is the proven cornerstone of primary dental health care promotion. In 2002 CWF was made mandatory at a national level in Israel, however a new government revoked these regulations in August 2014. "Maccabi" is the second largest national health care provider with 2.3 million members, "Maccabi-Dent", its dental branch, has 53 clinics, employing 1100 dentists. The aim of this study was to evaluate the cumulative effect on treatment rates 6 years after CWF was terminated in Israel, based on the number of dental treatments provided to children aged 3-12 years in "Maccabi-Dent" clinics.

METHODS

For this retrospective study, computerized dental treatment codes were collected. The "rate of treatment" was calculated by dividing the number of restorative treatments or extractions, by the number of individuals receiving treatment. The population size and the age group visiting the specific clinic were also considered.

RESULTS

The independent variables were fluoride concentration in drinking water, age and socioeconomic position (SEP). There was a significant increase in restorative dental treatments after 2014, (R2 = 0.0402), with approximately twice the number of treatments required in the absence of CWF. Age had a significant association (β =  - 0.389, p < 0.001) as did SEP (β = 0.086, p = 0.019).

CONCLUSION

After CWF cessation in Israel, rates of dental treatments significantly increased.

PRACTICAL IMPLICATION

By examining accepted notions with up-to-date information, new confirmatory evidence helps decision makers understand the importance of adding fluoride to drinking water.

Impact of water fluoridation on dental caries decline across racial and income subgroups of Brazilian adolescents

OBJECTIVES

The aim of this study was to assess the impact of community water fluoridation (CWF) on differences in dental caries decline across racial and socioeconomic subgroups of Brazilian adolescents.

METHODS

Two nationwide Brazilian population-based oral health surveys were used (Brazilian Oral Health Survey 2003 and 2010). In total, 7,198 adolescents from 15 years to 19 years old living in 50 cities investigated in both surveys were included. The mean numbers of untreated decayed teeth (DT) according to racial (Whites vs. Browns/Blacks) and socioeconomic subgroups (at or above the minimum wage per capita vs. under) were analysed. Difference-in-differences negative binomial regressions were adjusted by schooling, age, and sex. Decayed, missing, and filled teeth and DT prevalence, calculated as a categorical variable, were used in sensitivity analyses.

RESULTS

The adjusted difference of reduction in DT was similar across socioeconomic subgroups (β=-0.05; 95% confidence interval [CI], -0.45 to 0.35) and favoured, but not to a significant degree, Whites (β=-0.34; 95% CI, -0.74 to 0.04) compared to Brown/Blacks in fluoridated areas. In non-fluoridated areas, significant differences were observed in the mean number of DT, favouring the higher socioeconomic subgroup (β=-0.26; 95% CI, -0.53 to -0.01) and Whites (β=-0.40; 95% CI, -0.69 to -0.11) in relation to their counterparts. The sensitivity analyses confirmed the findings.

CONCLUSIONS

The similar reduction in DT across income subgroups suggests that CWF has had a beneficial effect on tackling income inequalities in dental caries within a 7-year timeframe.

Intersectoral collaboration and coordination mechanisms for implementing water fluoridation: Challenges from a case study in Brazil

OBJECTIVES

Community water fluoridation has been associated with better oral health conditions globally and reduced dental caries. While oral health policies are governed by the health sector agenda, water fluoridation is undertaken by public, private, and mixed public/private companies of the sanitation sector. The first aim of this study was to investigate the degree of intersectoral collaboration, and the second was to investigate how the coordination mechanisms are perceived by the sanitation agents of the sectors involved in water quality management, for the potential establishment of water fluoridation in a central-west state in Brazil.

METHODS

Semi-structured interviews were conducted with chief sanitation agents from nonprofit, profit, and mixed public/private companies responsible for water quality and fluoridation in a purposive sample. Theoretical frameworks of intersectoral collaboration and coordination mechanisms were used for analysis.

RESULTS

Twelve interviews were conducted. Informal collaboration was identified in the sanitation sector within companies involved in water provision. The main coordination mechanisms were network-type mechanisms, which involve consultations and knowledge sharing, and market-type mechanisms, which explore new job opportunities and cost-effectiveness, especially in water quality measures. Enabling themes (enablers) were identified, such as positive attitude toward including water quality and fluoridation in a collaborative health and sanitation common agenda. Moreover, fluoridation did not meet the regulatory and surveillance agenda at the state level, and until that moment, there was no proposal of the health sector for water fluoridation.

CONCLUSIONS

Partnership creation, consolidation, and shared mission, especially between health and sanitation sectors, were identified as main challenges for implementing water fluoridation policy.

Seeking community water fluoridation information on state health department websites

Community water fluoridation (CWF) is the most effective and equitable approach to preventing dental caries (tooth decay). Yet millions of Americans, especially those at highest risk of caries, do not know what CWF is or its preventive benefits. State health departments are responsible for educating their respective populations. Thus, this study assessed health department websites (N = 50) to determine if CWF content existed, the ease of finding it, and if it was written in plain language and for a consumer audience. We used the web component of the HLE2: The Health Literacy Environment of Hospitals and Health Centers (HLE2) to assess how easy or difficult it was to the navigate a website and find information. Forty-one websites had CWF information; 37 states had content written for a consumer audience. HLE2 scores ranged from 0 to 54 points (60 possible). Only five states had websites with a HLE2 score of 50 or higher. SHDs with higher HLE2 scores were easy to navigate and their content was written for a consumer audience. Study findings suggest most SHDs should improve their website’s CWF content and its accessibility to better promote the role of fluoridated water in preventing dental caries.

A Cross-Sectional Analysis of Community Water Fluoridation and Prevalence of Pediatric Dental Surgery Among Medicaid Enrollees

IMPORTANCE

Dental surgery under general anesthesia (DGA) is an ineffective, costly treatment for caries. Interventions to reduce the need for DGA are challenging because children's parents may not seek care until surgery is required. Community water fluoridation (CWF) effectively prevents early childhood caries, but its effectiveness in reducing severe early childhood caries is unknown.

OBJECTIVE

To determine whether access to CWF is associated with the prevalence of DGA.

DESIGN, SETTING, AND PARTICIPANTS

This is a cross-sectional analysis of Medicaid claims data from 2011 to 2012. Deidentified data were derived from Medicaid claims and enrollee files for Massachusetts, Texas, Connecticut, Illinois, and Florida for children aged 9 years and younger enrolled in either a fee-for-service or managed care plan through their state's Medicaid program. Linear regression models tested for associations between CWF and covariates. Multivariable linear regression models tested for associations between CWF and outcomes. Regression models included clustered SEs at the county level. Data analysis was performed from December 2018 to March 2020.

EXPOSURES

Access to CWF was determined by estimating the proportion of a county's total population that had access to a fluoridated public water system.

MAIN OUTCOMES AND MEASURES

The main outcome was county-level DGA prevalence. Other outcomes were caries-related visit prevalence and patient quality indicators (asthma and diabetes). Covariates included county-level demographic, socioeconomic, and dental practitioner variables.

RESULTS

A total of 436 counties within 5 states per year (872 county-year observations), were included in the analysis. Adjusted analysis revealed that a 10% increase in the proportion of county's population access to CWF was associated with lower caries-related visit prevalence (-0.45 percentage points; 95% CI, -0.59 to -0.31 percentage points; P < .001). Increasing CWF access in 10% increments was associated with decreased DGA prevalence in unadjusted analysis (-0.39 percentage points; 95% CI, -0.67 to -0.12 percentage points; P = .006) but not in adjusted analysis (-0.23 percentage points; 95% CI, -0.49 to 0.02 percentage points; P = .07). Increasing the proportion of county's access to CWF by 10% was not associated with the prevalence of asthma-related exacerbations (-0.02 percentage points; 95% CI, -0.10 to 0.05 percentage points; P = .53) or diabetes-related exacerbations (-0.0003 percentage points; 95% CI, -0.0014 to 0.0009 percentage points; P = .66).

CONCLUSIONS AND RELEVANCE

This study extends our understanding of CWF's benefits for children's oral health. Specifically, these findings suggest that increasing a population's access to CWF's is associated with decreased caries-related visits and may also be associated with use of dental surgical services within high-risk populations.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

This comprehensive review of the 2018 dental literature is provided to inform busy dentists about progress in the profession. Developed by the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, each author brings discipline-specific expertise to one of the 8 sections of the report including (1) prosthodontics; (2) periodontics, alveolar bone, and peri-implant tissues; (3) implant dentistry; (4) dental materials and therapeutics; (5) occlusion and temporomandibular disorders; (6) sleep-related breathing disorders; (7) oral medicine and oral and maxillofacial surgery; and (8) dental caries and cariology. The report targets important information that will likely influence day-to-day treatment decisions. Each review is not intended to stand alone but to update interested readers so that they may visit source materials if greater detail is desired. As the profession continues its march toward evidence-based clinical decision-making, an already voluminous library of potentially valuable dental literature continues to grow. It is the intention of this review and its authors to provide assistance in navigating the extensive dental literature published in 2018. It is our hope that readers find this work useful in the clinical management of patients moving forward.

Reduction of Dental Caries Among Children and Adolescents From a 15-Year Community Water Fluoridation Program in a Township Area, Korea

Since 2000, a community water fluoridation program (CWFP) has been implemented in Hapcheon for over 15 years. We aimed to evaluate the caries-reducing effect on permanent teeth after this implementation. In 2015, evaluation surveys were conducted by our study group, 498 subjects aged 8, 10, 12, and 15 years. As the control, 952 similarly aged subjects were selected from the Sixth Korean National Health and Nutrition Examination Survey (2013-2015 KNHANES). Data of a prospective cohort of 671 8-,10- and 12-year-olds, collected when CWFP started, were used for the evaluation. Caries-reducing effects were estimated by decayed, missing and filled teeth (DMFT) scores between CWFP and control groups, pre- and post-program. Confounders including the mean number of sealant teeth and gender were adjusted for. The mean adjusted DMFT scores of 10-, 12- and 15-year-olds in Hapcheon were significantly lower compared to KNHANES DMFT scores; in addition, those of 8-, 10- and 12-year-olds after the 15-year CWFP were significantly lower than in 2000. The caries-reducing effect among 12-year-olds was 37.6% compared to those recorded in KNHANES, and 67.4% compared to those in 2000. In conclusion, the caries-reducing effect was so high that health policy makers should consider CWFP as a priority policy for caries-reducing in Korean children and adolescents.