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

A systematic review on fluoride-induced epigenetic toxicity in mammals

Fluoride, one of the global groundwater contaminants, is ubiquitous in our day-to-day life from various natural and anthropogenic sources. Numerous in vitro, in vivo, and epidemiological studies are conducted to understand the effect of fluoride on biological systems. A low concentration of fluoride is reported to increase oral health, whereas chronic exposure to higher concentrations causes fluoride toxicity (fluorosis). It includes dental fluorosis, skeletal fluorosis, and fluoride toxicity in soft tissues. The mechanism of fluoride toxicity has been reviewed extensively. However, epigenetic regulation in fluoride toxicity has not been reviewed. This systematic review summarizes the current knowledge regarding fluoride-induced epigenetic toxicity in the in vitro, in vivo, and epidemiological studies in mammalian systems. We examined four databases for the association between epigenetics and fluoride exposure. Out of 932 articles (as of 31 March 2022), 39 met our inclusion criteria. Most of the studies focused on different genes, and overall, preliminary evidence for epigenetic regulation of fluoride toxicity was identified. We further highlight the need for epigenome studies rather than candidate genes and provide recommendations for future research. Our results indicate a correlation between fluoride exposure and epigenetic processes. Further studies are warranted to elucidate and confirm the mechanism of epigenetic alterations mediated fluoride toxicity.

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.

Does water fluoridation influence ethnic inequalities in caries in Brazilian children and adolescents?

OBJECTIVES

This study aimed to investigate the influence of community water fluoridation on ethnic inequalities in untreated dental caries among children and adolescents in Brazil while taking the human development context into account.

METHODS

Data from a nationwide Brazilian epidemiological population oral health survey were used (SB Brazil 2010). Outcomes were caries prevalence measured by the proportion of individuals with one or more untreated decayed teeth and caries severity defined by the mean number of untreated decayed teeth (DT). Three different contexts were considered: 1-cities with no water fluoridation; 2-cities with water fluoridation and low Human Development Index (HDI); and 3-cities with water fluoridation and high HDI. The exposure was ethnic/racial group (White, Pardo, Black) and covariates were age, sex and household income. Multilevel logistic and negative binomial regressions were performed with 6696 children (aged 5 years) and 11 585 adolescents (aged 12 and 15-19 years).

RESULTS

For both children and adolescents, ethnic differences in caries prevalence and mean DT were found in the nonfluoridated cities with low HDI and also in cities with high HDI, most of which were fluoridated. For example in nonfluoridated cities with low HDI, 5-year-old Pardo children were more likely to have untreated decay (OR = 1.22; 95% CI: 1.02, 1.46) and had more decayed teeth (RR = 1.18; 95% CI: 1.04, 1.34) than their White counterparts after adjusting for sex and household income. No statistically significant differences were observed in fluoridated cities with low HDI.

CONCLUSION

Water fluoridation appears to be associated with reduced ethnic inequalities in dental caries prevalence and mean DT among children and adolescents in more disadvantaged settings.

Sedentary behavior, unhealthy food consumption and dental caries in 12-year-old schoolchildren: a population-based study

This study analyzed the association between sedentary behavior (SB), unhealthy food consumption, and dental caries amongst 12-year-old schoolchildren. An epidemiological survey was carried out in the five largest cities (> 80,000 inhabitants) of the State of Mato Grosso do Sul, Brazil. Data were collected on decayed, missing and filled teeth index (DMFT), sociodemographic characteristics, SB, unhealthy food consumption, and water fluoridation status. The analysis was based on the theoretical framework established by J Sisson. Structural equation models were performed to test the association of dental caries experience with sociodemographic, contextual, and behavioral factors. The mean DMFT index in the five cities was 1.02 (95%CI: 0.39-1.66). Higher sedentary behavior (more than 2 hours/day) [standardized coefficient (SC) = 0.21 95%CI: 0.07-0.39] and higher unhealthy food consumption (more than 4 times/week) [SC = 0.23 (0.10-0.45)] were associated with higher DMFT index than their counterparts. Also, cities with fluoridated water were associated with lower DMFT index [SC = -0.85 (-1.20--0.50)]. Families who had a per capita income above the poverty line had a direct association with unhealthy food consumption [SC = -0.24 (-0.38--0.11)]. Unhealthy food consumption mediated the association of sedentary behavior on DMFT index [SC=0.07 (0.02-0.13)]. Sensitivity analysis confirmed the findings. Sedentary behavior mediated by unhealthy food consumption had a significant association with dental caries experience. Public policies must address transdisciplinary actions to reduce sedentary behavior and unhealthy food consumption and promote water fluoridation.

Ethnic Disparities in Dental Caries among Adolescents in China

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health-related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10-1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25-1.67), Tibetan (PRR, 1.39; 95% CI, 1.3-1.48), and Yi (PRR, 1.24; 95% CI, 1.04-1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.

Association Between Community Water Fluoridation and Severe Dental Caries Experience in 4-Year-Old New Zealand Children

IMPORTANCE

Robust contemporary epidemiologic evidence for the population-wide efficacy of reticulated community water fluoridation is required.

OBJECTIVE

To evaluate whether community water fluoridation is associated with the national rates of severe caries among 4-year-old children in New Zealand after accounting for key sociodemographic characteristics.

DESIGN, SETTING, AND PARTICIPANTS

This was a near whole population-level, natural, geospatial cross-sectional study of 4-year-old children who had a health and development assessment as part of the nationwide B4 School Check screening program conducted in New Zealand between July 1, 2010, and June 30, 2016. The extracted database included 391 677 children. However, geospatial information was missing for 18 558 children, another 32 939 children were unable to be geospatially matched, 5551 children resided in areas with changing fluoridation status, and 58 786 children had no oral health screen recorded, leaving 275 843 (70.4%) eligible children. Data were released in August 2019; statistical analysis was performed from September 2019 to December 2019.

EXPOSURES

Community water fluoridation status from 2011 through 2016.

MAIN OUTCOMES AND MEASURES

Severe caries experience derived from the "lift the lip" oral health screening. Analyses were adjusted for age, sex, ethnicity, area-level deprivation, and residential location differences. Multilevel mixed-effects logistic regression models were used. Sensitivity analyses based on multiple imputed data were undertaken to measure any differential influence of missing data.

RESULTS

In the eligible sample of 275 843 children, the median age was 4.3 years (interquartile range, 4.1-4.6 years), 141 451 children (51.3%) were boys, and 153 670 children (55.7%) resided within fluoridated areas. Severe caries were identified for 24 226 children (15.8%) in fluoridated and 17 135 children (14.0%) in unfluoridated areas, yielding an unadjusted odds ratio of 0.93 (95% CI, 0.90-0.95). However, in the adjusted analyses, children residing in areas without fluoridation had higher odds of severe caries compared with those within fluoridated areas (odds ratio, 1.21; 95% CI, 1.17-1.24). The population attributional fraction associated with unfluoridated community water was 5.6% (95% CI, 4.7%-6.6%) in a complete case analysis.

CONCLUSIONS AND RELEVANCE

This study finds that community water fluoridation continues to be associated with reduced prevalence of severe caries in the primary dentition of New Zealand's 4-year-old children.

Prevalence and Correlation of Dental Caries with its Specific Risk Factors in 5-15-year-old School-going Children in Urban Population of Ghaziabad

Dental caries is a rapidly emerging oral health problem amid the children with differing prevalence rate in different states of India. The data available from Ghaziabad city regarding dental caries are scarce; therefore, the study was conducted in 5–15-year school-going children in urban population of Ghaziabad.

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.

The Impact of Policy Modifiable Factors on Inequalities in Rates of Child Dental Caries in Australia

Background: Poor oral health in childhood can lead to adverse impacts later in life. We aimed to estimate the prevalence and population distribution of childhood dental caries in Australia and investigate factors that might ameliorate inequalities. Methods: Data from the nationally representative birth cohort Longitudinal Study of Australian Children (N = 5107), using questions assessing: The experience of dental caries during each biennial follow-up period (2–3 years to 10–11 years), socioeconomic position (SEP), and policy modifiable oral health factors. Results: The odds of dental caries were higher for children with lowest vs. highest SEP (adjusted OR (adjOR) 1.92, 95% CI 1.49–2.46), and lower where water was fluoridated to recommended levels (adjOR 0.53, 95% CI 0.43–0.64). There was no evidence of an association between caries experience and either reported sugary diet or tooth brushing. When SEP and fluoridation were considered in conjunction, compared to the highest SEP group with water fluoridation children in the lowest SEP with fluoridation had adjOR 1.54 for caries, (95% CI 1.14–2.07), and children in the lowest SEP without fluoridation had adjOR 4.06 (95% CI 2.88–5.42). For patterns of service use: The highest SEP group reported a greater percentage of service use in the absence of caries. Conclusions: Dental caries appears prevalent and is socially distributed in Australia. Policy efforts should consider how to ensure that children with dental caries receive adequate prevention and early care with equitable uptake.

Epidemiological profile of caries and need for dental extraction in a Kaingang adult Indigenous population

ABSTRACT: Introduction: The epidemiological profile of dental caries for Indigenous Peoples is complex and heterogeneous. The oral health of the Kaingang people, third largest Indigenous population from Brazil, has not been investigated so far. Objective: The purpose of this study was to assess the prevalence and severity of dental caries, in addition to the associated factors of the need of dental extraction among Kaingang adult Indigenous. Methods: A cross-sectional oral health survey was conducted among Kaingang adults aged from 35 to 44 years old living in the Guarita Indigenous Land, Rio Grande do Sul. Clinical exams were performed to analyze the conditions of dental crown and treatment needs. Results: A total of 107 Indigenous adults were examined. Mean DMFT score was 14.45 (± 5.80). Two-thirds of the DMFT score accounted for missing teeth. Anterior lower dentition presented the highest rates of sound teeth, whereas the lower first molars had the lowest. Need for dental extraction was observed in 34.58% and was associated with village location, time of last dental visit, and higher number of decayed teeth. Conclusion: The high frequencies of caries and missing teeth observed in this population indicate a lack of adequate assistance. It is essential to discuss health care models in order to combat avoidable social and health injustices.

Inequalities in dental caries experience among 4-year-old New Zealand children

OBJECTIVES

To investigate ethnic-specific deprivation gradients in early childhood dental caries experience considering different domains of deprivation.

METHODS

We used cross-sectional near whole population-level data on 318 321 four-year-olds attending the "B4 School check," a national health and development check in New Zealand, across 6 fiscal years (2010/2011 to 2015/2016). The "lift the lip" screening tool was used to estimate experience of any caries and severe caries. We investigated deprivation gradients using the Index of Multiple Deprivation (IMD), which measures seven domains of deprivation across 5958 geographical areas ("data zones"). Ethnicity was categorized into five groups: (i) Māori, (ii) Pacific, (iii) Asian, (iv) Middle Eastern, Latin American and African (MELAA) and (v) European & Other (combined). We used a random intercepts model to estimate mutually adjusted associations between deprivation, ethnicity, age, fiscal year, and evidence of any dental caries experience.

RESULTS

Reports of any caries experience decreased from 15.8% (95% CI: 15.7; 15.9%) to 14.7% 95% CI: 14.4; 14.8%), while reports of severe caries experience increased from 3.0% (95% CI: 3.0; 3.1%) to 4.4% (95% CI: 4.3; 4.5%) from 2010/2011 to 2015/2016. This varied by ethnicity with larger increases in severe caries for Pacific children from 7.1% (95% CI: 6.8; 7.4%) to 14.1% (95% CI: 13.7; 14.5%). There were deprivation gradients in dental caries experience with considerable variation by ethnicity and by domain of deprivation. The association between deprivation and dental caries experience was weakest for Asian children and was most pronounced for Pacific and Māori children.

CONCLUSION

Socioeconomic gradients in dental caries experience are evident by age 4 years, and these gradients vary by ethnicity and domain of deprivation.

Oral health status in Sichuan Province: findings from the oral health survey of Sichuan, 2015-2016

To investigate oral health status in the residents of Sichuan Province, southwest China, a cross-sectional study was performed using the latest Oral Health Survey Basic Methods recommended by the World Health Organization. A multistage stratified random cluster-sampling method was used to enroll participants from the following three groups: children aged 3-5 years, adolescents aged 12 years, and people aged 65-74 years. In these three groups, the mean numbers of teeth that were affected by caries were 3.28, 0.86 and 5.13, respectively, resulting in a prevalence of 63.47%, 37.20% and 83.20%, respectively. Relative to the high rate of decayed teeth, the prevalence of fillings was very low in all age groups (0.97%, 7.24% and 5.43%, respectively). In the 12-year-old adolescent group, only 3.61% had good pit and fissure sealing. In addition, the rate of dental fluorosis was 24.80%, and the Community Fluorosis Index value was 0.39. In the elder group, the community periodontal index was 2.92. The prevalence in the elderly of having lost at least one tooth was 75.54%. Additionally, 4.44% of these participants were edentulous. The incidence of dental prosthesis was 51.75%, the proportion with a removable partial denture, a fixed denture, full dentures, dental implants and an informal fixed bridge was 21.59%, 11.45%, 4.64%, 0 and 16.67%, respectively. In this study, 8.2% of the elderly participants were affected by different types of oral mucosal lesions. Among such lesions, recurrent aphthous ulcers were most prevalent (2.69%) and oral lichen planuses were second (1.6%). The conclusion presented in this survey is that oral diseases, especially dental caries and periodontal disease, are frequent and common in Sichuan province, China. Moreover, the treatment rate is very low, and primary prevention and treatment options are therefore urgently needed in this population.

Acculturation and its impact on the oral health status of Pacific children in New Zealand: findings from the Pacific Islands Families study

OBJECTIVES

Immigration and acculturation are increasingly recognized as important explanatory factors for health disparities, although their impact on oral health is less well understood. This study investigates the relationship between Pacific children's cultural orientation and oral health, after adjusting for potentially moderating and confounding variables.

METHODS

The Pacific Islands Families (PIF) study follows a cohort of Pacific infants born in 2000. PIF study participants' data from their last dental examination were extracted from service records, and matched to the cohort. A bi-directional acculturation classification, derived from maternal reports, was related to children's oral health indices in crude and adjusted analyses.

RESULTS

1,376 children were eligible, of whom 922 (67.0 percent) had mothers born outside New Zealand. Matching was successful for 970 (70.5 percent) children, with mean age 12.2 years (range: 6.8, 15.4 years). Significant differences were found between acculturation groups for children's tooth brushing frequency and school dental service enrollments but these differences did not moderate relationships between acculturation and oral health status. Unmet treatment need was significantly different between acculturation groups, with children of mothers having higher Pacific orientation having worse unmet needs than those with lower Pacific orientation. No other significant differences were noted.

CONCLUSIONS

Pacific children carry a disproportionate oral health burden, particularly amongst those with mothers more aligned to their Pacific culture. Strategies which enable Pacific people to re-shape their oral health understanding, together with reducing barriers to accessing dental health care, are needed to prevent a legacy of poor oral health in Pacific people within New Zealand.