The costs and benefits of water fluoridation in NZ

Impact of dental fluorosis on the oral health-related quality of life: a systematic review

OBJECTIVE

The aim of this systematic review is to investigate the literature to assess the effect of dental fluorosis on the Oral Health-Related Quality of Life (OHRQoL).

MATERIALS AND METHODS

Included studies were epidemiological investigations, clinical trials, or human studies that directly compared the impact on OHRQoL between individuals with dental fluorosis and those without, utilizing valid OHRQoL assessment tools. The searches were conducted up to March 2024 in databases, including PubMed, Scielo, LILACS, Scopus, Web of Science, Embase, and the Virtual Health Library. Additionally, gray literature sources such as Google Scholar, OpenGrey, Ibict/BDTD, and ProQuest were searched. Reference lists were also manually reviewed for potential eligible studies. The risk of bias in cohort studies was assessed using the Newcastle-Ottawa Scale (NOS), while its modified version was employed for cross-sectional studies. A narrative synthesis of the results was conducted.

RESULTS

16 studies were included in this Systematic Review. In total, 16,314 participants, aged 8 to 18, were assessed across the studies. Most of the included studies were cross-sectional, except for one cohort study. In assessing OHRQoL across different age groups and severities of dental fluorosis, the impact varied. A negative association between dental fluorosis and OHRQoL was found in 9 of the included studies, a positive association was found in 1 study, and no significative association was identified in 6 studies. Limitations in the included studies primarily pertained to cross-sectional designs, with significant issues such as the absence of sample size calculations, lack of non-response rate reporting, limited consideration of confounding factors, and substantial heterogeneity stemming from diverse diagnostic methods and assessment tools.

CONCLUSION

The findings of the systematic review demonstrate a complex and varied relationship between dental fluorosis and OHRQoL in children and adolescents. These conclusions may have limitations in scientific evidence. The findings emphasize the need for further investigations to explore the intricate aspects of this relationship and identify contributing factors to varying outcomes.

CLINICAL RELEVANCE

Dental caries preventive fluoridated measures might be indicated even if there would be a risk for mild dental fluorosis as the fluoridated public water.

REVIEW REGISTRATION

This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under number: CRD42020186552.

Evaluating the harmonization potential of oral health-related questionnaires in national longitudinal birth and child cohort surveys

BACKGROUND/OBJECTIVES

Effective use of longitudinal study data is challenging because of divergences in the construct definitions and measurement approaches over time, between studies and across disciplines. One approach to overcome these challenges is data harmonization. Data harmonization is a practice used to improve variable comparability and reduce heterogeneity across studies. This study describes the process used to evaluate the harmonization potential of oral health-related variables across each survey wave.

METHODS

National child cohort surveys with similar themes/objectives conducted in the last two decades were selected. The Maelstrom Research Guidelines were followed for harmonization potential evaluation.

RESULTS

Seven nationally representative child cohort surveys were included and questionnaires examined from 50 survey waves. Questionnaires were classified into three domains and fifteen constructs and summarized by age groups. A DataSchema (a list of core variables representing the suitable version of the oral health outcomes and risk factors) was compiled comprising 42 variables. For each study wave, the potential (or not) to generate each DataSchema variable was evaluated. Of the 2100 harmonization status assessments, 543 (26%) were complete. Approximately 50% of the DataSchema variables can be generated across at least four cohort surveys while only 10% (n = 4) variables can be generated across all surveys. For each survey, the DataSchema variables that can be generated ranged between 26% and 76%.

CONCLUSION

Data harmonization can improve the comparability of variables both within and across surveys. For future cohort surveys, the authors advocate more consistency and standardization in survey questionnaires within and between surveys.

Economic Evaluations of Preventive Interventions for Dental Caries and Periodontitis: A Systematic Review

OBJECTIVES

To critically examine the methods used for full economic evaluations of preventive interventions for dental caries and periodontitis.

METHODS

Published literature post-2000 was searched to April 2021. Based on a developed intervention classification framework for dental caries and periodontitis, only universal, selective or indicated interventions were included in this review. The Drummond 10-point checklist was used for quality appraisal.

RESULTS

Of 3,007 unique records screened for relevance, 73 studies were reviewed. Most model-based studies (61/73) used cost-effectiveness analysis (49%) or cost-benefit analysis (28%). Trial-based studies (16/73) commonly used cost-effectiveness analysis (59%). Four studies used both economic evaluation methods. Sixty-four papers (88%) were on dental caries, eight papers (11%) focused on periodontitis, and one paper (1%) included both oral diseases; 72% of model-based and 82% of trial-based studies were of good quality. The most frequently investigated dental caries preventive interventions were water fluoridation (universal intervention; cost-saving or cost-effective), fissure sealant and fluoride varnish (selective and indicated interventions; cost-effectiveness outcomes were inconsistent). Supportive periodontal therapy with oral health education (indicated intervention; cost-effective) was the most frequently evaluated preventive intervention for periodontitis. Thirty percent of studies with a time horizon > 1 year did not apply an appropriate discount rate and 26% did not comprehensively discuss other important considerations beyond the technical analysis.

CONCLUSIONS

Generic health outcome measures should be incorporated for economic evaluations on preventive interventions for dental caries and periodontitis, and an increased focus to prevent periodontitis using economic evaluation methods is needed to inform resource allocation and policy decision-making.

Evaluation of water fluoridation scheme in Cumbria: the CATFISH prospective longitudinal cohort study

Background

Water fluoridation was introduced in the UK against a background of high dental decay within the population. Levels of decay have dramatically reduced over the last 40 years following widespread use of fluoride toothpaste.

Objective

The aim of the CATFISH (Cumbrian Assessment of Teeth a Fluoride Intervention Study for Health) study was to address the question of whether or not the addition of fluoride to community drinking water, in a contemporary population, lead to a reduction in the number of children with caries and, if so, is this reduction cost-effective?

Design

A longitudinal prospective cohort design was used in two distinct recruited populations: (1) a birth cohort to assess systemic and topical effects of water fluoridation and (2) an older school cohort to assess the topical effects of drinking fluoridated water.

Setting

The study was conducted in Cumbria, UK. Broadly, the intervention group (i.e. individuals receiving fluoridated drinking water) were from the west of Cumbria and the control group were from the east of Cumbria.

Participants

Children who were lifetime residents of Cumbria were recruited. For the birth cohort, children were recruited at birth (2014–15), and followed until age 5 years. For the older school cohort, children were recruited at age 5 years (2013–14) and followed until the age of 11 years.

Intervention

The provision of a ‘reintroduced fluoridated water scheme’.

Main outcome measures

The primary outcome measure was the presence or absence of decay into dentine in the primary teeth (birth cohort) and permanent teeth (older school cohort). The cost per quality-adjusted life-year was also assessed.

Results

In the birth cohort (n = 1444), 17.4% of children in the intervention group had decay into dentine, compared with 21.4% of children in the control group. The evidence, after adjusting for deprivation, age and sex, with an adjusted odds ratio of 0.74 (95% confidence interval 0.56 to 0.98), suggested that water fluoridation was likely to have a modest beneficial effect. There was insufficient evidence of difference in the presence of decay in children in the older school cohort (n = 1192), with 19.1% of children in the intervention group having decay into dentine, compared with 21.9% of children in the control group (adjusted odds ratio 0.80, 95% confidence interval 0.58 to 1.09). The intervention was found to be likely to be cost-effective for both the birth cohort and the older school cohort at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. There was no significant difference in the performance of water fluoridation on caries experience across deprivation quintiles.

Conclusions

The prevalence of caries and the impact of water fluoridation was much smaller than previous studies have reported. The intervention was effective in the birth cohort group; however, the importance of the modest absolute reduction in caries (into dentine) needs to be considered against the use of other dental caries preventative measures. Longer-term follow-up will be required to fully understand the balance of benefits and potential risks (e.g. fluorosis) of water fluoridation in contemporary low-caries populations.

Limitations

The low response rates to the questionnaires reduced their value for generalisations. The observed numbers of children with decay and the postulated differences between the groups were far smaller than anticipated and, consequently, the power of the study was affected (i.e. increasing the uncertainty indicated in the confidence intervals).

Study registration

This study is registered as Integrated Research Application System 131824 and 149278.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 10, No. 11. See the NIHR Journals Library website for further project information.

Fluoridated water impact on tooth decay and fluorosis in 17-20-year-olds exposed to fluoride toothpaste

OBJECTIVE

To determine the impact of water fluoridation on the prevalence and severity of dental caries and fluorosis in individuals aged 17-20 years exposed to fluoride toothpaste.

METHODS

The study population consisted of 660 students from public schools, residents of areas supplied with fluoridated water (exposed group) or not (not exposed group). Students from both groups had access to fluoride toothpaste throughout life. A questionnaire about socioeconomic demographic aspects, conditions related to access and exposure to fluoridated water, and habits related to oral health was applied. Dental caries was measured by the DMFT index and dental fluorosis by the TF index. The chi-square test, t test, and subsequently logistic regression were applied for data analysis.

RESULTS

Caries experience (DMFT≠0) was significantly higher in students from areas not exposed to fluoridated water, after adjustments to clinical conditions, demographic socioeconomic profile, and hygiene habits. The DMFT mean (±SD) was significantly higher in students from areas not exposed to fluoridated water than exposed (3.83 [±3.28] and 2.48 [±2.71] respectively). The prevalence of very mild/mild and moderate fluorosis was 41.1% and 21% for students either exposed to fluoridated water or not, respectively.

CONCLUSION

Exposure to fluoridated water was associated with a lower prevalence and severity of tooth decay, in spite of the use of fluoridated toothpaste. The prevalence of dental fluorosis at all levels was higher in fluoridated areas, however, in both groups, there were few cases with esthetic implications.

Economic evaluations in water-fluoridation: a scoping review

Background

Community water fluoridation (CWF) is considered one of the 10 greatest public health achievements of the twentieth century and has been a cornerstone strategies for the prevention and control of dental caries in many countries. However, for decision-makers the effectiveness and safety of any given intervention is not always sufficient to decide on the best option. Economic evaluations (EE) provide key information that managers weigh, alongside other evidence. This study reviews the relevant literature on EE in CWF.

Methods

A systematic database search up to August 2019 was carried out using MEDLINE, EMBASE, Cochrane Library, LILACS, Paediatric Economic Database Evaluation and National Health Service Economic Evaluation Database. The review included full economic evaluations on CWF programs, written in English, Spanish or Portuguese. The selection process and data extraction were carried out by two researchers independently. A qualitative synthesis of the results was performed.

Results

Of 498 identified articles, 24 studies met the inclusion criteria; 11 corresponded to cost-benefit analysis; nine were cost-effectiveness analyses; and four cost-utility studies. Two cost-utility studies used Disability-Adjusted Life Years,, one used Quality-Adjusted Tooth Years, and another Quality-Adjusted Life Years. EEs were conducted in eight countries. All studies concluded that water fluoridation was a cost-effective strategy when it was compared with non-fluoridated communities, independently of the perspective, time horizon or discount rate applied. Four studies adopted a lifetime time horizon. The outcome measures included caries averted (n = 14) and savings cost of dental treatment (n = 4). Most of the studies reported a caries reduction effects between 25 and 40%.

Conclusion

Findings indicated that CWF represents an appropriate use of communities’ resources, using a range of economic evaluation methods and in different locations. These findings provide evidence to decision-makers which they could use as an aid to deciding on resource allocation.

Effects of Community Water Fluoridation on Dental Caries Disparities in Adolescents

Despite improvements in the prevalence of dental caries, disparities are still observed globally and in the U.S. This study examined whether community water fluoridation (CWF) reduced dental caries disparities in permanent teeth of 10- to 19-year-old schoolchildren in North Carolina. We used cross-sectional data representing K-12 schoolchildren in North Carolina (NC) public schools. A poisson regression model was used to determine whether the association between children’s parental educational attainment and the prevalence of dental caries of children differed by children’s lifetime CWF exposure. We analyzed data on 2075 students. Among the children without any CWF exposure in their life, statistically significant caries disparities by parental educational attainment were observed. Compared to the children of parents with more than high school education, the relative risk for those with a parent with a high school education was 1.16 (95% CI = 1.01, 1.33) and those with less than a high school education was 1.27 (95% CI = 1.02, 1.60). In contrast, these disparities were not observed among children exposed to CWF throughout their lives. Socioeconomic disparities in dental caries were not observed among 10–19-year-old schoolchildren with lifetime CWF exposure. CWF seemed to reduce dental caries disparities.

Teeth: Small but Mighty and Mighty Important. A Comprehensive Review of Children's Dental Health for Primary Care Clinicians

Healthy teeth allow us to eat and stay well-nourished. Although primary care clinicians receive limited training about teeth, given the common nature of dental problems, it is important that they understand and recognize normal and abnormal dental conditions and can implement primary and secondary prevention of dental conditions in their practice. PubMed has been used to search the scientific literature for evidence on the following topics: normal dental development, dental abnormalities, malocclusion, teething, dental caries and related epidemiology and prevention, fluoride, dental injury and its management and prevention; and identification, prevention and treatment of gingivitis and periodontal disease. Literature review relied on randomized controlled trials, meta-analyses, systematic reviews, and Cochrane reviews when relevant and available. Other sources of evidence included cohort and case-control studies. Consensus statements and expert opinion were used when there was a paucity of high-quality research studies. The literature has been synthesized on these topics to make them relevant to pediatric primary care clinicians, and as available, the strength of evidence has been characterized when making clinical recommendations.