Water fluoridation for the prevention of dental caries

Critique of the review of 'Water fluoridation for the prevention of dental caries' published by the Cochrane Collaboration in 2015

The Cochrane Review on water fluoridation for the prevention of dental caries was published in 2015 and attracted considerable interest and comment, especially in countries with extensive water fluoridation programmes. The Review had two objectives: (i) to evaluate the effects of water fluoridation (artificial or natural) on the prevention of dental caries, and (ii) to evaluate the effects of water fluoridation (artificial or natural) on dental fluorosis. The authors concluded, inter alia, that there was very little contemporary evidence, meeting the Review's inclusion criteria, that evaluated the effectiveness of water fluoridation for the prevention of dental caries. The purpose of this critique is to examine the conduct of the above Review, and to put it into context in the wider body of evidence regarding the effectiveness of water fluoridation. While the overall conclusion that water fluoridation is effective in caries prevention agrees with previous reviews, many important public health questions could not be answered by the Review because of the restrictive criteria used to judge adequacy of study design and risk of bias. The potential benefits of using wider criteria in order to achieve a fuller understanding of the effectiveness of water fluoridation are discussed.

[Access to oral health services in children under twelve years of age in Peru, 2014]

The aim of the study was to explore the patterns of dental health services access in children under twelve years of age in Peru. Data from 25,285 children under 12 years who participated in the Demographic and Family Health Survey of 2014 were reviewed. An exploratory spatial analysis was performed to project the proportions of children with access to dental health services, according to national regions, type of health service and urban or rural place of residence. The results show that of the total sample, 26.7% had access to dental health services in the last six months, 39.6% belonged to the age group 0-4 years, 40.6% lived in the Andean region and 58.3% lived in urban areas. The regions of Huancavelica, Apurimac, Ayacucho, Lima and Pasco had the highest percentages of access nationwide. In conclusion, there is low access to dental health services in the population under 12 years of age in Peru. The spatial distribution of access to dental health services allows regions to be identified and grouped according to similar access patterns, in order to better focus public health actions.

Comparisons of periodontal regenerative therapies: A meta-analysis on the long-term efficacy

AIM

We conducted a meta-analysis for the long-term differences in treatment outcomes between periodontal regeneration therapies and flap operation.

METHODS

A systematic literature search was conducted using the EMBASE, PubMed and Cochrane databases up to June 2016. Treatment outcomes were changes in probing pocket depth and clinical attachment level. We extracted data reported at different time points after periodontal surgery and incorporated all data into the same model. The restricted cubic spline regression was used to estimate the non-linear trend in treatment outcomes. As some studies reported outcomes at multiple time points, we considered several correlation structures for data reported by the same study.

RESULTS

A total of 52 randomized controlled trials were included in our longitudinal meta-analysis. The follow-up length ranged from 0.5 year to 10 years. The trends in the treatment outcomes were similar under different correlation structures. Enamel matrix derivatives (EMD) and guided tissue regeneration (GTR) achieved greater probing pocket depth (PPD) reduction and clinical attachment level (CAL) gain than flap operation (FO) in the long-term follow up, but no differences were found between EMD and GTR.

CONCLUSION

Compared with FO, periodontal regeneration surgeries achieved greater PPD reduction and gain in CAL after 1 year, and its effects may last for 5-10 years.

Outcomes Associated With Early Preventive Dental Care Among Medicaid-Enrolled Children in Alabama

Importance

There is a recommendation for children to have a dental home by 6 months of age, but there is limited evidence supporting the effectiveness of early preventive dental care or whether primary care providers (PCPs) can deliver it.

Objective

To investigate the effectiveness of preventive dental care in reducing caries-related treatment visits among Medicaid enrollees.

Design, Setting, and Participants

High-dimensional propensity scores were used to address selection bias for a retrospective cohort study of children continuously enrolled in coverage from the Alabama Medicaid Agency from birth between 2008 and 2012, adjusting for demographics, access to care, and general health service use.

Exposures

Children receiving preventive dental care prior to age 2 years from PCPs or dentists vs no preventive dental care.

Main Outcome and Measures

Two-part models estimated caries-related treatment and expenditures.

Results

Among 19 658 eligible children, 25.8% (n = 3658) received early preventive dental care, of whom 44% were black, 37.6% were white, and 16.3% were Hispanic. Compared with matched children without early preventive dental care, children with dentist-delivered preventive dental care more frequently had a subsequent caries-related treatment (20.6% vs 11.3%, P < .001), higher rate of visits (0.29 vs 0.15 per child-year, P < .001), and greater dental expenditures ($168 vs $87 per year, P < .001). Dentist-delivered preventive dental care was associated with an increase in the expected number of caries-related treatment visits by 0.14 per child per year (95% CI, 0.11-0.16) and caries-related treatment expenditures by $40.77 per child per year (95% CI, $30.48-$51.07). Primary care provider-delivered preventive dental care did not significantly affect caries-related treatment use or expenditures.

Conclusions and Relevance

Children with early preventive care visits from dentists were more likely to have subsequent dental care, including caries-related treatment, and greater expenditures than children without preventive dental care. There was no association with subsequent caries-related treatment and preventive dental care from PCPs. We observed no evidence of a benefit of early preventive dental care, regardless of the provider. Additional research beyond administrative data may be necessary to elucidate any benefits of early preventive dental care.

Mortality, hospital days and treatment costs of current and reduced sugar consumption in Israel

BACKGROUND

Consumption of sugar causes tooth decay, overweight and obesity related morbidities. This paper in response to the Minister of Health's request, provides estimates of the mortality, morbidity and health care costs attributable to sugar consumption in Israel along with the effects of reducing sugar consumption.

METHODS

Gender specific relative risks of many diseases from overweight (25 < =BMI < 30) and obesity (BMI > =30) were applied to the national gender specific prevalence rates of overweight and obesity in order to calculate the population attributable fraction (PAF) from overweight and obesity. National expenditure on these related diseases was calculated by applying disease-specific data from a recent Canadian study to estimates of disease specific general hospital expenditures in Israel. Disease specific costs attributable to overweight and obesity were estimated from the product of these expenditures and PAF. In addition national costs of treating caries in persons under 18 years of age from sugar were calculated. Similar calculations were made to estimate the burden from sugar in terms of mortality and hospital utilisation. A recent UK modelling study was used to estimate the effect of a national program to reduce calorific consumption of sugar from 12.45 to 10% in 5 years.

RESULTS

Conditions associated with overweight or obesity accounted annually for 6402 deaths (95% CI 3296-8760) and 268,009 hospital days. Dental costs attributable to sugar consumption were 264 million NIS. In total, obesity, overweight and sugar consumption accounted for 2449 million in direct treatment costs (0.21% of GDP), rising to 4027 million (0.35% of GDP) when indirect costs were included. A national program of reducing energy from sugar consumption from 12.45 to 10% over 5 years is considered have a very feasible short-term goal. Even if the program does not impose taxes on sugar consumption, this would save 778 million NIS as well as 1184 lives.

CONCLUSION

Sugar consumption causes a huge monetary and mortality burden. Estimates of potential decreases in this burden justify the current prioritisation given by the health minister of creating and implementing a national program to reduce sugar consumption, which is likely to be cost-saving (ie: averted treatment costs will exceed intervention costs).

Prevention of dental caries: A review of effective treatments

BACKGROUND

The objective of this study is to review medical and non medical treatments for prevention of caries.

MATERIAL AND METHODS

A comprehensive literature search of the most relevant and updated published studies from 01/01/2002 through December 2015 in PubMed/MEDLINE, Embase and Scopus databases regarding the efficacy of strategies and treatments aiming to prevent the development of caries was performed selecting papers on the basis of the Evidence-based Medicine Criteria.

RESULTS

We identified thirty systematic reviews on prevention of caries. Analyzing the data the retrieved literature, performance of prevention treatments seems to be high.

CONCLUSIONS

Prevention treatments may have a relevant impact on the avoiding the development of caries planning. Key words:Dental caries, prevention, fluoride.

Population-level interventions in government jurisdictions for dietary sodium reduction

BACKGROUND

Excess dietary sodium consumption is a risk factor for high blood pressure, stroke and cardiovascular disease. Currently, dietary sodium consumption in almost every country is too high. Excess sodium intake is associated with high blood pressure, which is common and costly and accounts for significant burden of disease. A large number of jurisdictions worldwide have implemented population-level dietary sodium reduction initiatives. No systematic review has examined the impact of these initiatives.

OBJECTIVES

• To assess the impact of population-level interventions for dietary sodium reduction in government jurisdictions worldwide.• To assess the differential impact of those initiatives by social and economic indicators.

SEARCH METHODS

We searched the following electronic databases from their start date to 5 January 2015: the Cochrane Central Register of Controlled Trials (CENTRAL); Cochrane Public Health Group Specialised Register; MEDLINE; MEDLINE In Process & Other Non-Indexed Citations; EMBASE; Effective Public Health Practice Project Database; Web of Science; Trials Register of Promoting Health Interventions (TRoPHI) databases; and Latin American Caribbean Health Sciences Literature (LILACS). We also searched grey literature, other national sources and references of included studies.This review was conducted in parallel with a comprehensive review of national sodium reduction efforts under way worldwide (Trieu 2015), through which we gained additional information directly from country contacts.We imposed no restrictions on language or publication status.

SELECTION CRITERIA

We included population-level initiatives (i.e. interventions that target whole populations, in this case, government jurisdictions, worldwide) for dietary sodium reduction, with at least one pre-intervention data point and at least one post-intervention data point of comparable jurisdiction. We included populations of all ages and the following types of study designs: cluster-randomised, controlled pre-post, interrupted time series and uncontrolled pre-post. We contacted study authors at different points in the review to ask for missing information.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data, and two review authors assessed risk of bias for each included initiative.We analysed the impact of initiatives by using estimates of sodium consumption from dietary surveys or urine samples. All estimates were converted to a common metric: salt intake in grams per day. We analysed impact by computing the mean change in salt intake (grams per day) from pre-intervention to post-intervention.

MAIN RESULTS

We reviewed a total of 881 full-text documents. From these, we identified 15 national initiatives, including more than 260,000 people, that met the inclusion criteria. None of the initiatives were provided in lower-middle-income or low-income countries. All initiatives except one used an uncontrolled pre-post study design.Because of high levels of study heterogeneity (I2 > 90%), we focused on individual initiatives rather than on pooled results.Ten initiatives provided sufficient data for quantitative analysis of impact (64,798 participants). As required by the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) method, we graded the evidence as very low due to the risk of bias of the included studies, as well as variation in the direction and size of effect across the studies. Five of these showed mean decreases in average daily salt intake per person from pre-intervention to post-intervention, ranging from 1.15 grams/day less (Finland) to 0.35 grams/day less (Ireland). Two initiatives showed mean increase in salt intake from pre-intervention to post-intervention: Canada (1.66) and Switzerland (0.80 grams/day more per person. The remaining initiatives did not show a statistically significant mean change.Seven of the 10 initiatives were multi-component and incorporated intervention activities of a structural nature (e.g. food product reformulation, food procurement policy in specific settings). Of those seven initiatives, four showed a statistically significant mean decrease in salt intake from pre-intervention to post-intervention, ranging from Finland to Ireland (see above), and one showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention (Switzerland; see above).Nine initiatives permitted quantitative analysis of differential impact by sex (men and women separately). For women, three initiatives (China, Finland, France) showed a statistically significant mean decrease, four (Austria, Netherlands, Switzerland, United Kingdom) showed no significant change and two (Canada, United States) showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention. For men, five initiatives (Austria, China, Finland, France, United Kingdom) showed a statistically significant mean decrease, three (Netherlands, Switzerland, United States) showed no significant change and one (Canada) showed a statistically significant mean increase in salt intake from pre-intervention to post-intervention.Information was insufficient to indicate whether a differential change in mean salt intake occurred from pre-intervention to post-intervention by other axes of equity included in the PROGRESS framework (e.g. education, place of residence).We identified no adverse effects of these initiatives.The number of initiatives was insufficient to permit other subgroup analyses, including stratification by intervention type, economic status of country and duration (or start year) of the initiative.Many studies had methodological strengths, including large, nationally representative samples of the population and rigorous measurement of dietary sodium intake. However, all studies were scored as having high risk of bias, reflecting the observational nature of the research and the use of an uncontrolled study design. The quality of evidence for the main outcome was low. We could perform a sensitivity analysis only for impact.

AUTHORS' CONCLUSIONS

Population-level interventions in government jurisdictions for dietary sodium reduction have the potential to result in population-wide reductions in salt intake from pre-intervention to post-intervention, particularly if they are multi-component (more than one intervention activity) and incorporate intervention activities of a structural nature (e.g. food product reformulation), and particularly amongst men. Heterogeneity across studies was significant, reflecting different contexts (population and setting) and initiative characteristics. Implementation of future initiatives should embed more effective means of evaluation to help us better understand the variation in the effects.

Portland Water Fluoridation: A Newspaper Analysis

Portland, Oregon is the largest city in the United States without community water fluoridation (CWF). A newspaper analysis was conducted of the failed 2013 CWF campaign to evaluate anti-fluoridation and pro-fluoridation messaging provided by newspapers during the campaign. News content was categorized by type and slant (pro-fluoridation, anti-fluoridation, or neutral) and 34 variables were tabulated (23 anti-fluoridation, 11 pro-fluoridation). Results showed overall messaging was slightly pro-fluoridation, as compared to anti-fluoridation or neutral content (35%, 32%, and 33% respectively). Editorial content was 85% pro-fluoridation and 15% anti-fluoridation. The most frequent anti-fluoridation variables were alternatives to water fluoridation, mass/forced medication and concerns about the political process. Conversely, tooth decay and social justice were the most commonly cited pro-fluoridation variables. Newspapers can be influential in shaping public policy opinions in the fight for community water fluoridation.

Does cessation of community water fluoridation lead to an increase in tooth decay? A systematic review of published studies

Background

Cessation of community water fluoridation (CWF) appears to be occurring with increasing frequency in some regions. Our objective was to comprehensively review published research on the impact of CWF cessation on dental caries.

Methods

We searched 13 multidisciplinary databases. Results were synthesised qualitatively and quantitatively.

Results

We identified 15 instances of CWF cessation (‘intervention’) in 13 countries, which covered a broad time frame (1956–2003) and diverse geographical and political/economic contexts. Overall, results were mixed, but pointed more to an increase in caries postcessation than otherwise. For example, of the 9 studies with at least moderate methodological quality based on criteria we developed for this review, 5 showed an increase in caries postcessation. 3 studies did not show an increase in caries postcessation; however, important postcessation changes (eg, implementation of alternative fluoride delivery programmes) and/or large-scale social change may have contributed to those effects. Of the 3 study groupings that permitted quantitative synthesis, 2 showed statistically significant mean overall increase in caries postcessation; however, quantitative synthesis results must be interpreted cautiously.

Conclusions

Overall, the published research points more to an increase in dental caries post-CWF cessation than otherwise. However, the literature is highly diverse and variable in methodological quality. To build this literature, it is important to exploit research opportunities presented by CWF cessation. Remaining knowledge gaps include the impact of CWF cessation on the distribution of dental caries (ie, equitable or not) and understanding the decision-making circumstances around CWF cessation.

Water fluoridation and ethnic inequities in dental caries profiles of New Zealand children aged 5 and 12-13 years: analysis of national cross-sectional registry databases for the decade 2004-2013

Background

Gross and important inequities have historically existed in the oral health profiles of New Zealand children. Following the New Zealand Government’s strategic oral health vision, launched in 2006, nationally collected information from 2004 to 2013 was used to analyze patterns in the prevalence of no obvious decay experience (caries-free) and mean decayed-missing-filled teeth indices over time and by community water fluoridation (CWF) and ethnic classifications in New Zealand children aged 5 years and in school year 8 (generally aged 12–13 years).

Methods

National aggregated data collected from children’s routine child oral health service dental examinations were retrieved, and combined with demographic information from Statistics New Zealand. Children’s CWF status was defined by the public water supply status of their school. Crude and standardized population estimates of caries-free prevalence and mean decayed-missing-filled teeth indices over time were derived. Unweighted linear regression models of main effects and two-factor interactions were investigated by age group.

Results

Dental examination data were available from 417,318 children aged 5 years and 471,333 year 8 children; of whom 93,715 (22.5 %) and 94,001 (19.9 %), respectively, were Māori. Dental examination coverage of Māori children was significantly less than their non-Māori counterparts (approximately 11 % and 14 % for aged 5 and year 8 children, respectively). Regression analysis revealed that caries-free prevalence and mean decayed-missing-filled teeth indices significantly improved over the study period for both age groups. Significant and sustained differences were observed between Māori and non-Māori children, and between CWF and non-CWF exposed groups. However, a convergence of dental profiles between non-Māori children in CWF and non-CWF regions was observed.

Discussion

Significant and important gains in New Zealand children’s oral health profiles appear to have been made over the last decade. Māori children continued to carry a disproportionate oral health burden, even for those in CWF regions. The apparent profile convergence between non-Māori children in CWF and non-CWF regions is noteworthy; although a likely consequence of demographic shifts and unmeasured confounders.

Conclusions

CWF itself did not remove disparities in caries levels between Māori and non-Māori children. Multiple, multi-pronged strategies are needed that overcome the array of factors which disadvantage Māori.

Equity in children's dental caries before and after cessation of community water fluoridation: differential impact by dental insurance status and geographic material deprivation

BACKGROUND

One of the main arguments made in favor of community water fluoridation is that it is equitable in its impact on dental caries (i.e., helps to offset inequities in dental caries). Although an equitable effect of fluoridation has been demonstrated in cross-sectional studies, it has not been studied in the context of cessation of community water fluoridation (CWF). The objective of this study was to compare the socio-economic patterns of children's dental caries (tooth decay) in Calgary, Canada, in 2009/10 when CWF was in place, and in 2013/14, after it had been discontinued.

METHODS

We analyzed data from population-based samples of schoolchildren (grade 2) in 2009/10 and 2013/14. Data on dental caries (decayed, missing, and filled primary and permanent teeth) were gathered via open mouth exams conducted in schools by registered dental hygienists. We examined the association between dental caries and 1) presence/absence of dental insurance and 2) small area index of material deprivation, using Poisson (zero-inflated) and logistic regression, for both time points separately. For small-area material deprivation at each time point, we also computed the concentration index of inequality for each outcome variable.

RESULTS

Statistically significant inequities by dental insurance status and by small area material deprivation were more apparent in 2013/14 than in 2009/10.

CONCLUSIONS

Results are consistent with increasing inequities in dental caries following cessation of CWF. However, further research is needed to 1) confirm the effects in a study that includes a comparison community, and 2) explore possible alternative reasons for the findings, including changes in treatment and preventive programming.

Public perceptions and scientific evidence for perceived harms/risks of community water fluoridation: An examination of online comments pertaining to fluoridation cessation in Calgary in 2011

OBJECTIVES

To examine the perceived harms/risks of fluoridation as expressed in online forums relating to cessation and aftermath in Calgary, specifically, 1) which harms/risks are mentioned, 2) for those harms/risks, what kinds of evidence are cited, 3) to what extent is scientific literature cited, and what is its quality, and 4) for a subset of harms/risks, what is known from the broader scientific literature?

METHODS

Relevant online comments were identified through free-text Internet searches, and those explicitly discussing the harms/risks of water fluoridation were extracted. Types of evidence mentioned were identified, and the scientific papers cited were reviewed. Finally, the broader scientific literature on two of the harms/risks was reviewed and synthesized.

SYNTHESIS

We identified 17 distinct groups of harms/risks, which spanned human body systems, the environment and non-human organisms. Most often, no evidence was cited. When evidence was cited, types included individuals viewed as authorities and personal experiences. Reference to scientific articles was rare, and those papers (n = 9) had significant methodological concerns. Our review of scientific literature on fluoride and 1) thyroid functioning and 2) phytoplankton revealed some negative effects of fluoride at concentrations exceeding maximum recommended levels (&gt;1.5 ppm).

CONCLUSION

The findings have implications for communication with the public about fluoridation. First, to the extent that the public consults the scientific literature, it is essential that the methodological limitations of a study, as well as its relevance to community water fluoridation, be widely and promptly communicated. Second, scientific evidence is only one component of why some people support or do not support fluoridation, and communication strategies must accommodate that reality.