An investigation into the potential anticaries benefits and contributions to mineral intake of bottled water

Interplay Between Minerals in Bottled Water and Fluoride Toothpaste and Caries Lesion Remineralization

OBJECTIVES

he aim of this in vitro study was to evaluate the effects of some bottled waters on fluoride toothpaste efficacy in enhancing caries lesion remineralization.

METHODS

Early caries lesions were created in bovine enamel specimens and stratified into treatment groups based on Vickers surface microhardness (VHN). The present study followed a two (fluoride and fluoride-free toothpaste) by five (four bottled waters and tap water) factorial design. The treatment groups were bottled water with the following attributes: (a) 309.9 ppm Ca/1.20 ppm F; (b) 118.4 ppm Ca/0.16 ppm F; (c) 1.00 ppm Ca/1.01 ppm F; and (d) 0.1 ppm Ca/0.04 ppm F and tap water (48.7 ppm Ca/0.7 ppm F). The five water groups were paired either with 1100 ppm fluoride or fluoride-free toothpaste, yielding 10 groups. Specimens were pH-cycled for 10 days with the daily regimen comprised of twice daily toothpaste slurry, with four exposures to water in between. VHN was measured again and the difference was calculated (ΔVHN). Data were analyzed using two-way ANOVA at a 5% significance level.

RESULTS

The two-way interaction between water and toothpaste was significant (p<0.001). All groups except fluoride-free toothpaste/bottled water with 0.1 ppm Ca/0.04 ppm F (p=0.411) had significant increases in VHN after pH cycling (p≤0.023). Fluoridated toothpaste resulted in a higher rate of remineralization compared to fluoride-free toothpaste (all p<0.001). Bottled water with 1.20 ppm F/309.9 ppm Ca exhibited the greatest extent of remineralization within fluoride toothpaste groups (p<0.001) and higher remineralization than lower fluoride water in fluoride-free toothpaste groups (p≤0.006). Within the fluoridated toothpaste group, tap water exhibited significantly less remineralization than all bottled waters (all p<0.001).

CONCLUSION

Within the limitation of this study, bottled water with higher fluoride and calcium concentrations might improve fluoridated toothpaste efficacy by enhancing remineralization of early enamel caries-like lesions.

Including calcium-fortified water or flour in modeled diets based on local foods could improve calcium intake for women, adolescent girls, and young children in Bangladesh, Uganda, and Guatemala

Adequate calcium intake is essential for health, especially for infants, children, adolescents, and women, yet is difficult to achieve with local foods in many low- and middle-income countries. Previous analysis found it was not always possible to identify food-based recommendations (FBRs) that reached the calcium population recommended intake (PRI) for these groups in Bangladesh, Guatemala, and Uganda. We have modeled the potential contribution of calcium-fortified drinking water or wheat flour to FBR sets, to fill the remaining intake gaps. Optimized diets containing fortified products, with calcium-rich local foods, achieved the calcium PRI for all target groups. Combining fortified water or flour with FBRs met dietary intake targets for adolescent girls in all geographies and allowed a reduction from 3-4 to the more feasible 1-2 FBRs. Water with a calcium concentration of 100 mg/L with FBRs was sufficient to meet calcium targets in Uganda, but higher concentrations (400-500 mg/L) were mostly required in Guatemala and Bangladesh. Combining calcium-fortified wheat flour at 400 mg/100 g of flour and the FBR for small fish resulted in diets meeting the calcium PRI in Bangladesh. Calcium-fortified water or flour could improve calcium intake for vulnerable populations, especially when combined with FBRs based on locally available foods.

Dietary Fluoride Intake by Children: When to Use a Fluoride Toothpaste?

Fluoride is recommended for its cariostatic effect, but excessive fluoride intake may have health risks. Increased prevalence of dental fluorosis in areas with low fluoride content in drinking water has been attributed to the inappropriate excessive intake of fluoride supplements (tablets and drops) and toothpaste ingestion. The aim of the present study was to estimate the fluoride intake and the risk of fluorosis in children (6 months-6 years) in the Castelli Romani area (province of Rome, Italy), which is volcanic, therefore with a higher concentration of fluorine. Measurements of the fluoride content in drinking water, mineral waters, vegetables and commercial toothpaste for children were performed. The fluoride concentrations of all samples were determined using a Fluoride Ion Selective Electrode (GLP 22, Crison, Esp). Data were analyzed by descriptive statistics. Differences between samples were determined by Student's t-test. The fluoride content in tap water samples collected from public sources averaged from 0.35 to 1.11 ppm. The Pavona area showed the highest content of fluoride with respect to the others (p ≤ 0.05). The fluoride content in mineral water samples averaged from 0.07 to 1.50 ppm. The fluoride content of some vegetables showed increased mean values when compared to control vegetables (p ≤ 0.05). Within the limitations of the present study, considerations should be made when prescribing fluoride toothpaste for infants (6 months-4 years) in the areas with high fluoride content, because involuntary ingestion is consistent.

Health risk assessment of nitrate and fluoride in bottled water: a case study of Iran

Bottled water use has become widespread in recent years. Many Iranian cities are located in regions with a hot and semi-hot climate, and the quality of drinking water is low in most of these areas. Nitrate and fluoride are chemical constituents of drinking water with significant health concerns since they can be harmful in concentrations higher than drinking water standards. This study aims to determine nitrate and fluoride concentrations in different bottled water brands in the study region; evaluate the non-carcinogenic health risks posed by nitrate and fluoride exposure via the ingestion of bottled water; and compare the measured nitrate and fluoride concentrations with the amounts reported on the bottle labels. Twenty bottled water brands were sampled, and their nitrate and fluoride amounts were determined using the spectrophotometry method. The results revealed that 100% of nitrate and 70% of fluoride in samples had concentrations greater than the levels reported on bottle labels. Minimum, maximum, and mean concentrations for nitrate were, respectively, 1.1, 28, and 8.37 mg/L, and for fluoride were 0.014, 2.36, and 0.63 mg/L. The hazard quotient (HQ) values due to nitrate intake were > 1 in 10% of the samples (n = 2) for both infants and children, indicating potential adverse non-carcinogenic health effects upon consumption. For fluoride intake, the potential adverse health effects (HQ > 1) for infants, children, teenagers, and adults were respectively high in 30, 20, 10, and 10% of the samples. For nitrate, the 95th centile for infants was 1.547, and for fluoride, it was 2.62, 2.19, 1.15, and 1 for infants, children, teenagers, and adults, respectively.