A Physiologically-Based Pharmacokinetic Modeling Approach Using Biomonitoring Data in Order to Assess the Contribution of Drinking Water for the Achievement of an Optimal Fluoride Dose for Dental Health in Children

Urinary Fluoride Levels among Canadians with and without Community Water Fluoridation

Drinking water is a major source of dietary fluoride intake in communities with water fluoridation. We examined the association between urinary fluoride adjusted for specific gravity (UFSG) and tap water fluoride levels, by age and sex, among individuals living in Canada. Participants included 1629 individuals aged 3 to 79 years from Cycle 3 (2012-2013) of the Canadian Health Measures Survey. We used multiple linear regression to estimate unique associations of tap water fluoride levels, age, sex, ethnicity, body mass index (BMI), use of fluoride-containing dental products, smoking in the home, and tea consumption with UFSG. UFSG concentration was significantly higher among participants who received fluoridated drinking water (mean = 1.06 mg/L, standard deviation = 0.83) than among those who did not (M = 0.58 mg/L, SD = 0.47), p < 0.01. UFSG increased over adulthood (ages 19 to 79). Higher UFSG concentration was associated with being female, tea drinking, and smoking in the home. In conclusion, community water fluoridation is a major source of contemporary fluoride exposure for Canadians. Lifestyle factors including tea consumption, as well as demographic variables such as age and sex, also predict urinary fluoride level, and are therefore important factors when interpreting population-based fluoride biomonitoring data.

Early childhood caries and oral health care of Hong Kong preschool children

Surveys have shown that the prevalence of early childhood caries (ECC) among 5-year-old children decreased from 63% in 1993 to 55% in 2017. Caries experience was unevenly distributed; 81% of the caries lesions were found in 26% of the children. Risk factors, including oral hygiene practice behaviors, sugar consumption, parental oral health-related knowledge, and sociodemographic backgrounds, were significantly related to ECC. Oral health promotion aimed at managing the burden of ECC has been implemented. Water fluoridation was launched in 1961, and the fluoride concentration has been adjusted to 0.5 ppm since 1988. It is considered an important dental public health measure in Hong Kong. The Department of Health set up the Oral Health Education Unit in 1989 to deliver oral health education to further improve the oral health of preschool children. Other nongovernmental organizations also launched short-term oral health promotion programs for preschool children. However, no significant change in the prevalence of ECC has been observed in the recent two decades. There is a necessity to revisit dental public health policies and develop effective evidence-based strategies to encourage changes in oral health-related behaviors to forestall the impending epidemic of ECC in Hong Kong.