Assessment of Fluoride and pH Levels in a Range of Ready-to-Drink Children’s Beverages Marketed in Malaysia

This study aimed to determine the fluoride and pH levels of beverages likely to be consumed by children in Malaysia and to estimate daily fluoride intake from consumption of these beverages. A convenience sampling of 120 ready-to-drink beverages were purchased and categorised into 11 groups (UHT recombined milk, fresh milk [pasteurised], cultured milk [probiotic], yogurt beverages, fresh fruit juices, fruit flavoured beverages, soy-based beverages, malt-based beverages, tea, carbonated beverages and bottled waters). Fluoride concentration was measured using a fluoride ion-selective electrode while the pH level was measured using a pH meter. The fluoride concentration in the beverages ranged from 0.02±0.00 mg/L to 2.77±0.06 mg/L. Tea was found to have the highest fluoride concentration. The intake of fluoride from consumption of other types of beverages is below the lowest-observed-adverseeffect level (except tea). The pH of the beverages included in the study ranged from 2.20±0.01 to 7.76±0.00. Carbonated beverages (mean pH: 2.98±0.50) were found to be extremely acidic followed by fresh fruit juices (mean pH: 3.38±0.34) and fruit flavoured beverages (mean pH: 3.90±0.92). The correlation between fluoride and pH levels was weak, τ = 0.058 and not statistically significant (p

Geochemical characterization and assessment of fluoride sources in groundwater of Siloam area, Limpopo Province, South Africa

Siloam’s groundwater is reportedly characterized by high fluoride. In response to the reported high incidence of dental fluorosis in the area, sources of elevated fluoride in the groundwater were investigated. Total fluoride (TF) was determined using Ion Chromatograph and Fluoride Ion Selective Electrode. The mineral composition of rocks and soils were determined using X-ray Fluorescence and X-ray diffraction, respectively. Results revealed that groundwater fluoride concentration ranged from 3.92 to 4.95 mg/L. Na-Cl water type was found to be dominant in the water samples. TF content of the rocks and soils ranged from 10 to 2000 mg/L. Leachates were obtained by making a slurry from the samples at a predetermined temperature and time. TF in leachates ranged between 0.27 and 14.88 mg/L and 0.05 to 10.40 mg/L at induced, and non-induced temperatures, respectively. The possible source of fluoride has been previously inferred to be caused by fluorite minerals occurring at greater depth. However, this study proves that fluoride decreases with depth and the elevated fluoride in the groundwater is caused by smectite-kaolinite clay, muscovite and chlorite minerals abundant in the area. Geothermal temperature exhibited by the groundwater in the area is a major factor enhancing the release of fluoride from the clay materials.

No Association was Detected between Polymorphism of COL1A2 Genes and Occurrence of Dental Fluorosis Among the Subjects Living in a Fluorosis-Endemic Area of India

Objective: To determine any genetic association of COL1A2 polymorphism and the occurrence of dental fluorosis within an Indian human dental fluorosis population. Material and Methods: Fifty-six (56) subjects from two groups i.e. cases with dental fluorosis from the Pavagada population (n=29) and a control group (n=27) without fluorosis, were explored. The ages ranged between 15 and 76 years (mean 50.8 years) were included, and the male to female ratio was 70:30. The severity of dental fluorosis was graded using WHO’s Thylstrup-Fejerskov index (TF), and the concentration of fluoride was determined by a fluoride ion selective electrode (ISE). Genomic DNA was extracted using the standard phenol-chloroform method. The rs412777 and rs414408 polymorphism in COL1A2 were genotyped using the Sanger sequence method. Results: Genotype distributions for rs412777 within each group were: AA 41%, AC 51%, and CC 7% for dental fluorosis participants, and AA 56%, AC 46%, and CC 0% for the control participants. Conclusions: The rs412777 and rs414408 polymorphisms in the COL1A2gene showed no significant association between COL1A2 and the occurrence of dental fluorosis amongst this Indian population.

Comparison of Different Total Ionic Strength Adjustment Buffer Compositions for Determination of Low Level Fluoride in Environmental Water Samples with Fluoride Ion Selective Electrode

Background Fluoride content of environmental water samples collected from the vicinity of Pilanesberg National Park was determined using a fluoride ion selective electrode (F−ISE). Different total ionic strength adjustment buffers (TISABs) EDTA, CDTA, Citrate and Acetate buffers, were compared for their effectiveness in releasing fluorine into the solution in its ionic form, by adjusting the pH and ionic strength of the solution, as well as by chelating polyvalent cations present in the samples. Nine water samples were collected from different sites around the park, where there is a decommissioned fluorspar mine, and an extinct volcano; for fluoride content. Quantification was carried out by means of multipoint calibration covering the range of interest in all treatments. Result The fluoride concentration was calculated using the Nernest equation with values obtained from the calibration graph. It was found that CDTA and EDTA buffers were the best TISABs as they produced a better linearity, slope and recovery in that order, where as the other acetate also produced better parameters and results than the untreated water samples. Conclusion CDTA and EDTA TISAB solutions perform better than the others for fluoride content determination from environmental water samples.

Transmembrane Fluoride Transport by a Cyclic Azapeptide With Two β-Turns

Diverse classes of anion transporters have been developed, most of which focus on the transmembrane chloride transport due to its significance in living systems. Fluoride transport has, to some extent, been overlooked despite the importance of fluoride channels in bacterial survival. Here, we report the design and synthesis of a cyclic azapeptide (a peptide-based N-amidothiourea, 1), as a transporter for fluoride transportation through a confined cavity that encapsulates fluoride, together with acyclic control compounds, the analogs 2 and 3. Cyclic receptor 1 exhibits more stable β-turn structures than the control compounds 2 and 3 and affords a confined cavity containing multiple inner –NH protons that serve as hydrogen bond donors to bind anions. It is noteworthy that the cyclic receptor 1 shows the capacity to selectively transport fluoride across a lipid bilayer on the basis of the osmotic and fluoride ion-selective electrode (ISE) assays, during which an electrogenic anion transport mechanism is found operative, whereas no transmembrane transport activity was found with 2 and 3, despite the fact that 2 and 3 are also able to bind fluoride via the thiourea moieties. These results demonstrate that the encapsulation of an anionic guest within a cyclic host compound is key to enhancing the anion transport activity and selectivity.

Bioavailable fluoride in calcium-containing dentifrices

Calcium added to dentifrices can complex with fluoride ions to reduce intra-oral bioavailability and therefore efficacy in preventing dental caries. Six commercially available dentifrices containing different types of calcium and fluoride were analyzed for total and bioavailable fluoride levels by adding 10 g of dentifrice to 30 mL of distilled deionized water and mixing vigorously for 1 min to simulate toothbrushing. One milliliter of the dentifrice/water slurry was immediately centrifuged and the supernatant removed for bioavailable fluoride analysis and the mixed slurry prior to centrifugation used for total fluoride analysis using a modified microdiffusion method. The concentration of fluoride was determined using a fluoride ion-selective electrode calibrated with internal fluoride standards. All the dentifrices had similar total fluoride concentrations to those indicated on their labels (94% to 105%). However, only one dentifrice that contained calcium in the form of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) had almost 100% (97%) of fluoride in bioavailable form. The other dentifrices contained calcium carbonate and they exhibited significantly (p < 0.001) lower bioavailable fluoride levels (27% to 61%), through the generation of poorly soluble fluoride phases. The saliva biomimetic CPP, as CPP-ACP, in a dentifrice stabilised calcium and fluoride ions to maintain fluoride’s bioavailability.

La concentración de fluoruro en las aguas consumidas en la Región de Murcia no es suficiente para prevenir la caries dental

Introducción: La caries sigue siendo la enfermedad crónica más frecuente en el niño y es considerada un problema de salud pública. El flúor es la principal medida protectora contra la caries dental y el agua de consumo es la principal fuente de ingesta de flúor.Objetivo: El objetivo de nuestro trabajo fue calcular la concentración de ión fluoruro en el agua de abastecimiento de 10 zonas y en 10 aguas embotelladas comercializadas en la Región de Murcia.Material y Métodos: La concentración de fluoruro en las aguas se determinó con un electrodo ion–selectivo para flúor previamente calibrado con patrones de fluoruro preparados con TISAB II.Resultados: En el agua de abastecimiento, se detectaron concentraciones de fluoruro entre 0.09 y0.18 mgF/L (ppm) en las aguas embotelladas la concentración de fluoruro varió desde 0.04 a 0.50 ppm.Conclusiones: El fluoruro está presente en aguas consumidas en la Región de Murcia pero enconcentraciones que no alcanzan niveles preventivos para la caries dental. Es necesario prescribir suplementos de flúor en niños con alto riesgo de caries y para ello se deben contabilizar todas las fuentes externas de flúor, incluido el agua. Introduction: Dental caries remains the most frequent chronic disease in childhood and is considered a public health problem. Fluoride has proven effectiveness in the prevention of caries and drinking water is the main source of fluoride intake. The objective of this study was to determine fluoride concentrations in tap water from 10 areas and in 10 bottled waters sold in the Region of Murcia.Materials and Methods: The concentration of fluoride in water was determined using a fluoride ion-selective electrode with a direct technique previously calibrated with standard fluoride concentrations prepared with TISAB II.Results: In tap water, fluoride concentrations from 0.09 to 0.18 mgF/L (ppm) were detected; in bottled waters the concentration of fluoride varied from 0.04 to 0.50 ppm.Conclusion: Fluoride is present in the water consumed in the Region of Murcia but in concentrations that do not prevent dental caries. Fluoride supplements should be prescribed in children at high risk of caries, and for this, all external sources of fluoride intake, including water, must be accounted for.

Effect of the polishing procedure and surface sealant application on fluoride release

Objective: This study aimed to assess the effect of the polishing procedure and surface sealant application on the fluoride release of restorative materials. Material and Methods: The groups were consisted of using five different restorative materials were employed: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer and Fuji IX GP. 30 disk-shaped specimens (8x2 mm) were prepared from each material. Each group was subdivided into three groups considering finishing procedures: Mylar strip, polishing with Super-Snap discs, G-Coat Plus application after polishing with Super-Snap discs. The amount of fluoride released into distilled water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours, followed by measurement on days 3, 7, 15, 21, and 28. Surface analysis of the materials was performed with SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy). The data were statistically analyzed using two-way repeated measure ANOVA and LSD test (p=0.05). Results: The highest amount of fluoride released was measured after the first 24 h for all materials. Beautifil II released less fluoride than other materials in all measurement periods (p<0.05). After polishing, the amount of fluoride released from all materials except Beautifil II increased (p<0.05). The application of G-Coat Plus did not impact the amount of fluoride release of any materials (p>0.05). EDS analysis showed the most percentage of oxygen in all materials. Conclusion: The polishing procedure might induce an increase in fluoride release of glass ionomer-based materials, and the application of G-Coat Plus cannot affect the amount of fluoride release. Keywords Energy dispersive x-ray spectroscopy; Fluoride; Glass ionomer cement.

simplified protocol to determine total fluoride concentration in NaF/ silica-based toothpastes

Aim: To determine total fluoride (TF) concentration in Na2FPO3/Ca-based toothpastes, using fluoride ion selective electrode (F-ISE) by the direct technique, it is necessary to use acid (Ac+) to hydrolyze the FPO3 2- ion and to dissolve insoluble fluoride salts bound to the abrasive. For NaF/silicabased toothpastes, the use of acid is not necessary (Ac-) and a simplified protocol could be followed. Methods: Thus, we evaluated TF concentration in seven brands of NaF/silicabased toothpastes, following the validated conventional Cury’s protocol (Ac+) or a simplification of this protocol (Ac-). Fluoride was analyzed with ISE calibrated with fluoride standard solutions prepared in the same conditions as the samples (Ac+ or Ac-). Results: The mean (±SD; n=21) of TF concentrations (μg F/g) found by Ac+ (971.3±191.2) and Ac- (982.4±201.3) protocols were not statistically different (t test, p=0.22). The TF concentrations found agree with those declared by the manufacturers, except for one toothpaste imported from China. Conclusion: The findings suggest that the determination of fluoride in NaF/silica-based toothpastes can be accurately made using a simplified protocol of analysis.