Fluorosis and Dental Caries in Mexican Schoolchildren Residing in Areas with Different Water Fluoride Concentrations and Receiving Fluoridated Salt

Abstract

Objective: To explore the association between fluoride in drinking water and the prevalence and severity of fluorosis and dental caries in children living in communities receiving fluoridated salt. Material and Methods: Participants were schoolchildren (n = 457) living in two rural areas of the State of Morelos, Mexico, where the water fluoride concentration was 0.70 or 1.50 ppm. Dental caries status was assessed using Pitts’ criteria. Lesions that were classified as D₃ (decayed) were identified to determine the decayed, missing, and filled teeth index (D₃MFT). Fluorosis was assessed using the Thylstrup-Fejerskov Index (TFI). Information regarding drinking water source and oral hygiene practices (tooth brushing frequency, dentifrice use, and oral hygiene index) was obtained. Results: The prevalence of fluorosis (TFI ≥1) in communities with 0.70 and 1.50 ppm water fluoride was 39.4 and 60.5% (p = 0.014), respectively, while the prevalence of more severe forms (TFI ≥4) was 7.9 and 25.5% (p < 0.001), respectively. The mean D₃MFT was 0.49 (±1.01) in the 0.70 ppm community and 0.61 (±1.47) in the 1.50 ppm community (p = 0.349). A logistic regression model for caries (D₃ >1) showed that higher fluorosis categories (TFI 5–6 OR = 6.81, p = 0.001) were associated with higher caries experience, adjusted by age, number of teeth present, tooth brushing frequency, bottled water use, and natural water fluoride concentration. Conclusions: The prevalence of fluorosis was associated with the water fluoride concentration. Fluorosis at moderate and severe levels was associated with a higher prevalence of dental caries, compared with lesser degrees of fluorosis. The impact of dental fluorosis should be considered in dental public health programs.

The effect of non-fluoride factors on risk of dental fluorosis: Evidence from rural populations of the Main Ethiopian Rift

“…An elevated level of fluoride (F − ) in drinking water is a wellrecognized risk factor of dental and skeletal fluorosis, conditions which affect millions of people worldwide across many countries: e.g., in China, Mexico, India, Iran, parts of Africa, and the United States (Beltrán-Aguilar et al, 2010;Ding et al, 2011;García-Pérez et al, 2013;Hussain et al, 2010;Meyer-Lueckel et al, 2011;Ozsvath, 2006). For example, in Mexico the prevalence of fluorosis is 60.5% among residents of communities with F − level higher than 1.5 mg/l (ppm) (García-Pérez et al, 2013).…”

“…For example, in Mexico the prevalence of fluorosis is 60.5% among residents of communities with F − level higher than 1.5 mg/l (ppm) (García-Pérez et al, 2013). In the U.S., at the beginning of the 2000s 23% of individuals aged 6-39 years old had mild or greater enamel fluorosis (Beltrán-Aguilar et al, 2005).…”

Is severe early childhood caries predictive of caries and fluorosis in permanent teeth? Ten-year follow-up

“…Several risk factors for the development of fluorosis have been studied. The most common were the comparison between the use of children's and standard toothpaste 20 and water consumption in areas with or without fluoridation 7,21 . In the present study, the non-acceptance of oral hygiene by the children decreased the chance of developing fluorosis by 70%.…”

“…This fluoride intake can occur by the direct consumption of fluoridated water 7 , foods prepared with such water 8 and by the accidental or inadvertent toothpaste ingestion 9 in children under six years of age.…”

Assessment of fluoride in groundwater and urine, and prevalence of fluorosis among school children in Haryana, India

“…But, higher levels of fluoride (> 1.5 mg/l) may result in dental or skeletal fluorosis depending on the intensity and duration of exposure. Apart from drinking water, exposure may also occur through bioavailable fluoride present in milk, food, meat (IPCS 2002), toothpaste/dentifrice, tea, tobacco (Yadav et al 2007), fluoridated salt (García-Pérez et al 2013), etc. United States Environmental Protection Agency (USEPA) recommended range on fluoride in drinking water is 0.7-1.2 mg/l, effectively setting the maximum level at the lower end (0.7 mg/l) to maximize dental caries protection benefits and to prevent excessive fluoride exposure in the population which receives fluoridated salt.…”