Geochemical characterization of fluoride in water, table salt, active sediment, rock and soil samples, and its possible relationship with the prevalence of enamel fluorosis in children in four municipalities of the department of Huila (Colombia)

A Systematic Review and Meta-Analysis of the Relationship Between the Severity of Dental Fluorosis and Fluoride Biomarkers in Endemic Areas

The intake of high concentrations of fluoride, mainly through drinking water, diet and fluoridated dentifrices, produces fluorosis, which in its early stages is manifested as dental fluorosis (DF). To recognize exposure to fluoride in endemic areas and to evaluate the risk of developing health impairment, the WHO has established several biomarkers that are used to determine systemic fluorine (F^-) exposure. Thus, the aim of this study was to conduct a systematic review and meta-analysis of the relationship between the severity of DF and fluoride biomarkers in endemic areas. The protocol of this study was previously registered as CRD42021244974. A digital search was carried out in PubMed/Medline, SpringerLink, Scopus, Cochrane and Google Scholar by employing the keywords "urine", "nails", "hair", "plasma", "saliva" and "dental fluorosis" for the original studies with content associated with F^- for the biomarkers and DF. The mean difference was established as the effect measure for the meta-analysis. Seven studies fulfilled the eligibility criteria, among which five assessed urine and two employed nails as fluoride biomarkers. A positive significant difference was found between the biomarkers and the severity of DF (0.27, p < 0.001) and individually for each biomarker (urine: 0.14, p = 0.001; nails: 0.88, p < 0.05). The F^- concentration in urine and nails is correlated with the severity of DF, with the most evident differences between healthy individuals and those with mild severity. Both biomarkers are adequate to assess this relationship in endemic areas of fluoride and DF.

Dental Fluorosis according to Birth Cohort and Fluoride Markers in an Endemic Region of Colombia

Objectives

To analyze changes in the dental fluorosis (DF) incidence according to a birth cohort and explore current exposure to DF in a case series.

Methods

Repeated cross-sectional study of two periods: 2015 and 2018. Two standardized examiners registered DF using the Thylstrup-Fejerskov index in permanent teeth of children aged 7–18 years. Period and birth cohort frequencies were estimated by a generalized linear model, binomial family, and logarithmic link function. Period estimates are presented as prevalence ratios (PR) and birth cohort estimates as cumulative incidence ratios (RR); 95% confidence intervals and P values are reported. In a subsample of 37 volunteers (12.29 ± 2.63 years), the fluoride (F) concentration in toenails was measured using the HMDS diffusion method and an ion-specific electrode. Other samples from the local environment such as food, soil, and coal were also collected.

Results

In 274 children, we found that nonsignificant increases between periods (PR = 1.17; 95% CI: 0.89–1.55) were not explained by birth cohort effects. A total of 37.8% of the subsample had a toenail F concentration ≥2 μg F/g. The salty snacks and seasoning had the highest F concentrations among local environmental samples.

Conclusion

In this population with a high DF frequency according to birth cohort and the evaluated period, the study of soil, coal, and food samples indicated a continued F exposure. F concentration found in the toenails shows a moderate F exposure; nearly a third of the children and adolescents exceeded the adopted threshold of 2 μg F/g. It is important to monitor and explore changes in exposure in highly affected population.

Oral health of 12-year-old children in Quito, Ecuador: a population-based epidemiological survey

BACKGROUND

There is a paucity of population-based surveys on oral health conditions in Ecuador. Thus, the aim of this study was to conduct an epidemiological survey with a representative sample of children aged 12 years from public schools of Quito, Ecuador. The aim of this initial report was to describe the methodology used in the survey, as well to present results regarding calibration procedures and prevalence of oral-health related outcomes.

METHODS

We invited 33 public schools' coordinators from the urban area of Quito, and 1100 children (12 years old) to take part in this study. Six trained and calibrated examiners conducted clinical examinations using oral mirrors and ball-ended probes to assess: dental caries, traumatic dental injuries, malocclusion, gingival bleeding, presence of calculus and fluorosis. Children also responded a questionnaire on Oral Health-Related Quality of Life (OHRQoL). Individual sociodemographic data was collected through a questionnaire sent to parents. Moreover, some contextual data on school environment (infrastructure conditions, promotion of health practices and negative episodes) were also evaluated. Prevalence values, crude and weighted by sampling weights, and 95% confidence intervals (95%CI) were calculated.

RESULTS

Nine hundred and ninety-eight children from 31 schools were examined from March to May 2017. The adjusted prevalence values (95%CI) for the six outcomes evaluated were: dental caries = 60.3% (55.3 to 65.0%); traumatic dental injuries = 20.7% (17.2 to 24.8%); dental fluorosis = 63.7% (58.5 to 68.5%); gingival bleeding = 92.0% (87.1 to 95.2%); presence of calculus = 69.9 (60.5 to 77.9%); and malocclusion = 25.8% (21.8 to 30.3%). Adjusted mean of number of decayed, missed or filled permanent teeth (DMF-T) was 1.61 (1.37 to 1.84). Results on OHRQoL and other contextual variables will be reported in other articles.

CONCLUSION

The prevalence of the majority of oral health problems in 12-year-old children from public schools in Quito-Ecuador was compatible with those observed in other similar cities. However, periodontal health and fluorosis seem to be highly prevalent in children from Quito.