Fluoride-specific Electrode Research Articles

The in vitro assessment of resin coating materials containing calcium phosphate, bioactive glass, and polylysine for glass ionomer cement restorations

Objective: Glass ionomer cements (GICs) require protective surface coatings to enhance their clinical performance. This study developed novel protective resin coatings for GICs containing monocalcium phosphate monohydrate (MCPM), bioactive glass nanoparticles (BAGs), and poly-L-lysine (PLS) and evaluated their physical, mechanical, and biological properties when applied to GICs. Materials and methods: Experimental resin coating materials were formulated with 5–10 wt% of MCPM, BAGs, and PLS. The degree of monomer conversion was measured usingAttenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) (n = 6). GICs coated with the experimental materials were evaluated for biaxial flexural strength and modulus after 24 h water immersion using a universal testing machine (n = 8). Vickers surface microhardness up to 4 weeks of water immersion was also determined (n = 5). Fluoride and elemental release in water were analyzed using a fluoride-specific electrode and inductively coupled plasma optical emission spectrometry (n = 3). Cell viability was assessed using an MTT assay with mouse fibrosarcoma (n = 3). A commercial resin coating (EQUIA Forte Coat, EQ) served as control. Data were analyzed using one-way ANOVA and Tukey HSD test. Results: While EQ showed higher monomer conversion (87%) compared to experimental materials (72–74%) (p < 0.05), GICs coated with experimental materials demonstrated comparable strength to EQ-coated GICs. The experimental coatings exhibited similar F, Al, Na, and Si releases to EQ-coated GICs, with enhanced P release. All experimental coatings exhibited comparable cell viability (>70%) to the commercial material. Conclusion: The novel GIC protective coatings containing MCPM, BAGs, and PLS demonstrated acceptable in vitro performance comparable to commercial materials while potentially offering enhanced remineralization through increased elemental release.

Comparative evaluation of fluoride release profiles in new glass ionomer cements and conventional type II GIC: Implications for cariostatic efficacy

The fluoride release characteristics of two new Glass Ionomer Cements (GICs), Equia Forte HT and Micron Bioactive, with a conventional Type II restorative GIC is of interest. Fluoride release, a crucial cariostatic property, was evaluated using 18 disc specimens prepared in disposable silicone molds and stored in deionized water for 15 days. Measurements taken on days 1, 3, 7, and 14 with a fluoride ion-specific electrode showed that Equia Forte HT exhibited the highest fluoride release, followed by Micron Bioactive and Type II GIC. Statistical analysis, including ANOVA, confirmed significant differences among the groups, highlighting the superior performance of Equia Forte HT. These findings emphasize the importance of selecting GICs with optimal fluoride release for effective dental restorations and call for further research into their long-term clinical performance.

Effect of a 1.1% NaF toothpaste containing Sr/F-doped bioactive glass on irradiated demineralized dentin: an in vitro study

ObjectivePatients receiving head and neck radiation are at high risk for radiation caries. This study aimed to evaluate the remineralizing effects of an experimental 1.1% NaF (5000 ppmF) toothpaste containing Sr/F-doped bioactive glass nanoparticles (BAG or B) on demineralized irradiated dentin.Materials and methodsFluoride concentration and pH stability of materials upon mixing with water were assessed using a fluoride-specific electrode (n = 3) for up to 3 months. Elemental release of materials in water was determined using ICP-OES (n = 3). Fourteen extracted molars were irradiated with a cumulative dose of 70 Gy. Each tooth was sectioned into 4 specimens (n = 14/group), demineralized, and subjected to pH cycling for 14 days. Groups were treated with Prevident (PV), E5000, E5000B, and deionized water twice daily. Remineralization was assessed using ATR-FTIR (mineral-to-collagen ratio) (n = 14). Mineral precipitation was additionally examined with SEM-EDX. The in vitro cytotoxicity of the materials on L929 mouse fibrosarcoma was evaluated with the MTT test (n = 3). Kruskal-Wallis test, followed by Dunn’s procedure, was used to compare the data between groups.ResultPV demonstrated greater pH and fluoride release stability than the experimental materials. E5000B exhibited a slight reduction of fluoride release (p < 0.01, R²=0.656) and an increase in pH with time (p = 0.006, R²=0.233). The highest increase in mineral-to-collagen ratio at 14 days was detected with PV (p < 0.05). E5000B also showed a significantly higher ratio than E5000 (p = 0.014). SEM-EDX detected mineral precipitation on dentin treated with PV and E5000B but not in E5000 and DI. The cell viability of PV (56%) was significantly lower than that of E5000 (94%) and E5000B (89%) (p < 0.05).ConclusionThe use of 5000 ppm fluoride toothpaste enhanced the remineralization of irradiated demineralized dentin, highlighting a potentially valuable strategy for preventing radiation caries. Adding bioactive glass further promoted remineralization but may require formulation adjustments to maintain toothpaste stability for clinical use.

Impact of Calcium Lactate Pretreatment on Enamel Fluoride Uptake: A Comparative In Vitro Study of Different Fluoride Types and Concentrations.

(1) Background: This study aimed to establish the effect of calcium lactate enamel pretreatment related to different fluoride types and concentrations on the enamel uptake of alkali-soluble fluorides. (2) Materials: In a blind and randomized in vitro study, a total of 60 teeth are used. The first 30 teeth were cut and randomly allocated into one of the following treatments: (A) calcium lactate pretreatment followed by three different fluoride solutions; (B) the "Fluoride only" group, with slabs treated with three different fluoride solutions; (C) the "Calcium only" group, with slabs treated with calcium lactate solution; (D) slabs treated with deionized water (negative control group). The next 30 teeth underwent all the above described group procedures but were treated with lower fluoride concentrations. Fluoride was extracted from enamel using 1 M KOH solution and analyzed using a fluoride ion-specific electrode. (3) Results: The findings revealed that slabs treated with NaF following calcium lactate pretreatment exhibited significantly greater enamel uptake of alkali-soluble fluoride compared to other substrates. This significant effect was not observed at lower fluoride concentrations. (4) Conclusion: The study demonstrates that pretreatment with calcium lactate followed by treatment with NaF at 226 ppm F significantly enhances the uptake of alkali-soluble fluoride in enamel compared to other fluoride types.

Evaluation of setting kinetics, mechanical strength, ion release, and cytotoxicity of high-strength glass ionomer cement contained elastomeric micelles

BackgroundLow mechanical properties are the main limitation of glass ionomer cements (GICs). The incorporation of elastomeric micelles is expected to enhance the strength of GICs without detrimentally affecting their physical properties and biocompatibility. This study compared the chemical and mechanical properties, as well as the cytotoxicity, of elastomeric micelles-containing glass ionomer cement (DeltaFil, DT) with commonly used materials, including EQUIA Forte Fil (EF), Fuji IX GP Extra (F9), and Ketac Molar (KT).MethodPowder particles of GICs were examined with SEM-EDX. Setting kinetics were assessed using ATR-FTIR. Biaxial flexural strength/modulus and Vickers surface microhardness were measured after immersion in water for 24 h and 4 weeks. The release of F, Al, Sr, and P in water over 8 weeks was analyzed using a fluoride-specific electrode and ICP-OES. The toxicity of the material extract on mouse fibroblasts was also evaluated.ResultsHigh fluoride levels in the powder were detected with EF and F9. DT demonstrated an initial delay followed by a faster acid reaction compared to other cements, suggesting an improved snap set. DT also exhibited superior flexural strength than other materials at both 24 h and 4 weeks but lower surface microhardness (p < 0.05). EF and F9 showed higher release of F, Al, and P than DT and KT. There was no statistically significant difference in fibroblast viability among the tested materials (p > 0.05).ConclusionsElastomeric micelles-containing glass ionomer cement (DT) exhibited satisfactory mechanical properties and cytocompatibility compared with other materials. DT could, therefore, potentially be considered an alternative high-strength GIC for load-bearing restorations.

Effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary glass ionomer restorations.

To evaluate the effect of various surface coating methods on surface roughness, micromorphological analysis and fluoride release from contemporary resin-modified and conventional glass ionomer restorations. A total of 72 permanent human molars were used in this study. The teeth were randomly assigned into 2 groups according to type of restorative materials used; resin modified glass ionomer cement and conventional glass ionomer (SDI Limited. Bayswater Victoria, Australia). Each group was subdivided into 3 subgroups according to the application of coat material; Sub-group1: without application of coat; Sub-group2: manufacturer recommended coat was applied and sub-group3: customized (vaseline) coat was applied. Each group was then subdivided into two divisions according to the time of testing; immediate (after 24h) and delayed (after 6 months of storage). Three specimens from each sub-group were selected for surface roughness test (AFM) and another 3 specimens for the micromorphological analysis using scanning electron microscope (SEM). For the fluoride release test, a total of 60 cylindrical discs were used (n = 60). The discs were randomly split into 2 groups according to type of restorative materials used (n = 30); resin modified glass ionomer cement and conventional glass ionomer. Each group was subdivided into 3 subgroups (n = 10) according to the application of the coat material; Sub-group1: without application of coat; Sub-group2: with the manufacturer recommended coat and sub-group3: with application of customized (vaseline) coat. Data for each test was then collected, tabulated, were collected, tabulated, and tested for the normality with Shapiro-Wilk test. Based on the outcome of normality test, the significant effects of variables were assessed using appropriate statistical analysis testing methods. Regarding the data obtained from surface roughness test, Shapiro-Wilk test showed normal distribution pattern of all values (p > 0.05). Accordingly, Two-way ANOVA outcome showed that the 'type of restoration' or 'test time' had statistically significant effect on the AFM test (p < 0.05). Regarding Fluoride specific ion electrode test 2-way ANOVA followed by Least Significant Difference (LSD) Post-hoc test revealed significant difference among the groups (p < 0.05). It showed that SDI GIC group after 14 days of measurement had the highest mean of fluoride release (36.38 ± 3.16 PPM) and SDI RMGIC after 30 days of measurement had the second highest mean of fluoride release (43.28 ± 1.89 PPM). Finally, regarding the micromorphological analysis using SEM, a slight difference was observed between the studied groups. Based on the results of this study, various coatings enhance surface roughness in the initial 24h of restoration insertion. Different coat types seems that have no influence on fluoride release and the micromorphological features of the restoration/dentin interface.

Dose-response relationship between toothpaste soluble fluoride absorbed in the gastrointestinal tract and saliva fluoride secretion

Aim: This study aimed to evaluate if there is a dose-response relationship between toothpaste chemically soluble fluoride absorbed in the gastrointestinal tract and fluoride secreted by saliva, giving support to the use of saliva as surrogate for plasma fluoride. Methods: A 4-phase single blind study was conducted, in which 10 participants were subjected in each phase to one of the assigned treatment groups: group I: fresh sample of a Na2FPO3/CaCO3-based toothpaste with 1,334 μg F/g of total soluble fluoride (TSF) and groups II–IV: aged samples of this toothpaste presenting TSF concentrations of 1,128, 808, and 687 μg F/g, respectively. In all phases, the participants ingested an amount of toothpaste equivalent to 70.0 μg F/Kg body weight, as total fluoride (TF). Saliva and blood samples were collected before (baseline) and up to 180 min after toothpaste ingestion as indicator of fluoride bioavailability. F concentration in saliva and blood plasma was determined with a fluoride ion-specific electrode. The areas under the curve (AUC) of F concentration versus time (AUC = ng F/mL × min) and the peaks of fluoride concentration (Cmax) in saliva and plasma were calculated. Results: A significant correlation between mg of TSF ingested and the AUC (r=0.47; p&lt;0.01), and Cmax (r=0.59; p&lt;0.01) in saliva was found; for TF, the correlation was not significant (p&gt;0.05). In addition, the correlations between plasma and saliva fluoride concentrations were statistically significant for AUC (r=0.55; p&lt;0.01) as for Cmax (r=0.68; p&lt;0.01). Conclusion: The findings support that saliva can be used as a systemic biomarker of bioavailable fluoride present in Na2FPO3/ CaCO3-based toothpaste.

Nutritional qualities and fluoride content of different date (Phoenix dactylifer) varieties consumed in Morocco

The date is a fruit of the palm family (Phoenix dactylifer), grown in Morocco in the southern regions. It is a very important fruit in the Moroccan table, especially during Ramadan (9th month of the Islamic calendar, a lunar calendar consisting of 354 days), where it becomes an essential food that is very nutritious and invigorating to the breaking of the fast added to milk. The present work aimed to determine the contents of mineral elements (fluorine, calcium, magnesium and chlorides) and sugar levels (Brix, glucose) of 12 varieties: Ajwa (Saudi Arabia), Deglet nour (Algeria), Anbara (Saudi Arabia), Anbara (United Arab Emirates), Boufeggous (Errachidia; Morocco), Aziza (Figuig; Morocco), Majhoul (Erfoud; Morocco) Majhoul (Errachidia; Morocco), Elkhalsse (Tafilalt; Morocco) Tarzawa (Tafilalt; Morocco), Deglet nour (Tunisia), Majhoul Sghir (Tafilalt; Morocco)) of dates marketed in Morocco of North African and Middle Eastern origin. Fluoride analyses were performed using a fluoride-specific ion electrode (HI-4110). The analyses of Ca, Mg, Cl and glucose levels were performed by Spectrophotometric methods. The results of the fluoride levels revealed in the different varieties of dates varied from 0.26 to 1.05 mg in 100g of fresh weight. The sucrose and glucose levels varied between 11.8 g to 17.75 g and 18 to 40.9 g in 100g of fresh date weight, respectively. The Mg, Ca and Cl levels varied between 46.89 to 93.71mg, 11.20 to 279.28 mg and 30.66 to 47.33 mg in 100g fresh date weight, respectively. Thus, it is possible to classify the varieties of dates on the basis of their nutritional qualities and mode of consumption and to warn the population about their consumption in excess with the risk (if any) of an attack of dental or osseous fluorosis.

Anticaries potential of a fluoride foam.

Foam has been used worldwide as a vehicle for the professional application of fluoride and hypothetically should have the same anticaries potential as conventional fluoride gel (F-gel) in terms of the formation of reaction products with enamel. Thus, the ability of Flúor Care® foam (FGM, Joinville, SC, Brazil, 12,300 ppm F, acidulated) to react with enamel was evaluated in comparison with Flúor gel® (DFL, Rio de Janeiro, RJ, Brazil, 12,300 ppm F, acidulated). Slabs (n=10/group) of sound enamel and with caries lesion were used, in which the concentrations of total fluoride (TF), and loosely (CaF2-like) and firmly (FAp) bound types were determined. The importance of agitation during application was previously tested. The determinations were made with fluoride ion-specific electrode and the results were expressed in μg F/cm² of the treated enamel area. ANOVA and Tukey tests were used to analyze the difference among treatments, independently for sound and carious enamel. The agitation of the products during application significantly increased the reactivity of the foam (p<0.05), but not that of the gel (p>0.05). The foam did not differ from F-gel (p>0.05) concerning the formation of TF and CaF2-like in sound or carious enamel. Regarding FAp, the foam did not differ from F-gel (p>0.05) in the carious enamel, but the concentration in the sound was lower (p<0.05). The results show that this commercial fluoride foam tested needs to be agitated during application to improve its reactivity with enamel, which raises a question about other brands.

Ion Selective Electrode (ISE) Method for Determination of Total Fluorine and Total Organic Fluorine in Packaging Substrates

Various testing methods and techniques have been used to identify and quantify per- and polyfluoroalkyl substances (PFAS) in food packaging. A common indirect measurement of PFAS is total fluorine (TF) and total organic fluorine (TOF). These methods are critical in rapidly screening food packaging materials for the >9000 PFAS and are often globally used for regulatory limits. However, this destructive approach requires careful sample preparation, combustion, and the analysis of the solution by a fluoride-specific electrode. The method described herein is a cost-effective, rapid, quantitative, and externally validated initial screening of packaging materials for fluoro-chemistry. This study presents validated protocols for measuring TF and TOF in packaging substrates using oxygen combustion sample preparation coupled with fluoride ion-selective electrode (F-ISE); the materials and required equipment are provided, and the step-by-step procedure from sample preparation to the analysis are described, including critical steps to minimize contamination and interferences during sample preparation.

Defluoridation potential of indigenous thirst-quenching herbal products commonly used in Kerala, India

Background: Drinking fluoride-contaminated water is a severe health hazard problem. Fluorosis -both skeletal and dental- is an important clinical and public health problem in about 24 countries including India. The best method to overcome the problem of excess fluoride in drinking water is defluoridation. Adsorption methods are simple, economical, and globally pursued techniques. Thirst-quenching herbal products locally called ‘Dahashamini’ are plant parts that are used during boiling drinking water. Possessing a defluoridation potential is an added benefit. Methods: Two grams of each of dried and ground Zingiber officinale, Elettaria cardamomum, Eugenia caryophyllus, Coriandrum sativum, Acacia catechu, Caesalpinia sapans, Vetiveria zizanioides, Cuminum cyminum, and Hemidesmus indicus, were added to 100 millilitres of fluoridated water of baseline concentrations of 5 and 10 ppm, boiled till its boiling point, and cooled. The samples were then filtered and analyzed for fluoride content using fluoride ion specific electrode method. Statistical analysis was done using one-way ANOVA, followed by Tukey’s post hoc test for pair-wise comparison. Results: Caesalpinia sapans, Vetiveria zizanioides, Acacia catechu, Eugenia caryophyllus, and Coriandrum sativum, had a significant ability to adsorb fluoride from fluoridated water, with an efficiency ranging from 12% to 56% (at a baseline concentration of 10 ppm) and 19% to 82% (at a baseline concentration of 5 ppm). Conclusion: The study indicates the possibility of the use of five ingredients in developing a cost-effective and acceptable method of defluoridation based on the adsorption method.

Analysis of the fluoride levels of well water and tea consumed by the Moroccan population in different rural areas

Fluoride plays a fundamental part in human health. However, continued ingestion of excessive fluoride may cause significant negative health effects on people, ranging from mild dental fluorosis to crippling skeletal fluorosis, depending on the level and time of exposure to fluorides. In provincial areas, the presence of fluoride in well water may be due to natural factors or human activities.The reason for our work was to evaluate the level of tainting of groundwater by fluorides from various areas in Morocco situated in rural and agricultural areas, where the main wellspring of consumable water is well water, and the reasons for fluorosis in this area. The 44 samples were taken in seven Moroccan regions: Had Soualem-Berrechid, Kenitra, Fez, Tit Mellil, Sidi Slimane-Sidi Kacem-Zirara, Larache, and Brachoua, and 12 samples of tea were taken from different souks and commercials in Morocco.Fluoride dosing measurements in well water were performed using the potentiometric technique using the fluoride-specific ion electrode (HI-4110) at room temperature, while the determination of fluorine in tea is done by the spectrophotometric method.The results of fluoride levels revealed in different well waters from different regions range from 0.2 to 6.58 mg/l. For the green and black tea samples, the fluorine content varies between 0.48 and 1.60 mg/l for the 10 min infusion and between 0.93 and 2.7 mg/l for the 30 min infusion. These results make it possible to warn the population facing the risk of developing dental fluorosis by limiting the amount of fluoride ingested by the consumed foods.

Salivary fluoride concentration following toothbrushing with and without rinsing: a randomised controlled trial

BackgroundCaries prevalence has declined significantly since the introduction of fluoridated toothpaste. There have been several developments regarding specific active fluoride ingredients but not enough evidence to support one over the other. The purpose of this double-blind randomized controlled trial was to compare salivary fluoride concentrations of different fluoride formulations in the form of toothpaste with and without post-brushing water rinsing in adults.MethodsThe study included 120 participants who were randomly assigned to one of 12 groups (10 participants/group). The toothpaste formulas investigated included (1) fluoride-free (0 ppmF); (2) sodium fluoride (1450 ppmF); (3) sodium monofluorophosphate (1450 ppmF); (4) sodium fluoride and monofluorophosphate combined (1450 ppmF); (5) stannous fluoride and sodium fluoride combined (1450 ppmF); and (6) amine fluoride (1400 ppmF). Block randomisation was used to assign each participant to one of the 12 groups. Participants brushed with 1.0 g of one of the six different toothpaste formulations either with or without post-brushing water rinsing. Saliva was collected at six different times (baseline and at 1, 15, 30, 60, and 90 min/s post-brushing). Samples were analysed using a fluoride ion-specific sensitive electrode connected to an ion analyser.ResultsThe demographic characteristics of the participants were not significantly different among the groups (P > 0.05). Time, toothpaste formulation, and post-brushing rinsing routines had significant effects on saliva fluoride retention (P < 0.05). Amine fluoride-containing toothpaste was the only formula that showed statistically significantly higher concentrations of salivary fluoride at 90 min in both the rinsing and non-rinsing groups. Sodium monofluorophosphate toothpaste did not result in a significant difference compared to the control group at any time point, in both rinsing and non-rinsing groups.ConclusionsBased on the results from this study, no rinsing after toothbrushing in adults can be recommended when sodium monofluorophosphate containing toothpaste formula is used. It also concludes that amine fluoride resulted in a significantly higher saliva fluoride concentration at 90 min in both the rinsing and non-rinsing groups compared to other fluoride toothpaste formulations.Registry: Protocol Registration and Results System (ClinicalTrials.gov).Clinical trial registration number: NCT02740803 (15/04/2016).

In-vitro evaluation of the shear bond strength and fluoride release of a new bioactive dental composite material.

BackgroundThe aim of this study was (1) to determine and compare the shear bond strength (SBS) of a bioactive composite “Activa Bioactive Restorative” with and without bonding agent and a nanocomposite “Filtek Z350 XT/Z350” and (2) to measure and compare the amount of fluoride release from a bioactive composite “Activa Bioactive Restorative” and a glass ionomer ”Equia forte”. Material and MethodsForty two dentin surfaces from freshly extracted human molars were prepared for shear bond strength testing. The specimens were randomly divided into three equal groups. The restorative materials were applied to all dentin surfaces according to the manufacturer’s instructions, using a special jig (Ultradent) in the following manner : Group 1 (Activa Bioactive Restorative with adhesive), Group 2 (Activa Bioactive Restorative without adhesive) and Group 3 (Filtek Z350 XT/Z350). The bonded specimens were subjected to thermocycling in 5°C and 55°C water baths then tested for SBS in a universal testing machine (1 mm/minute). Kolmogorov-Smirnov and Levene tests were used to evaluate the distribution of the variable and the equality of variances respectively and a Student’s T- test was applied to compare the mean strength between the groups. In the next test, thirty disc shaped specimens were fabricated using Activa BioActive restorative and Equia Forte; 15 specimens from each material. The specimens of each group were immersed separately in 5 ml of deionized water. Fluoride release was measured daily throughout 15 days using a fluoride-specific ion electrode and an ion-analyzer. Repeated measures analysis of variance with one within-subject factor (time) and one between-subject factor (Activa Bioactive / Equia Forte) was applied to compare the amount of released fluoride between groups and within time. It was followed by univariate analyses and Bonferroni multiple comparisons tests. ResultsThe mean shear bond strength of Activa Bioactive Restorative with adhesive was found to be 17.379 (± 8.5043) MPa and 19.443(± 8.3293) MPa for the Filtek Z350 XT/Z350 group. There was no significant difference between both groups. Regarding fluoride release, the amount of Fluoride released was significantly greater in the Equia Forte group compared to the Activa Bioactive group (-p-value<0.05). The mean amount of Fluoride has significantly decreased over time with Activa Bioactive group (-p-value<0.001); it showed the highest fluoride release during the first 24 hours post-setting. Also in the Equia Forte group, the mean amount of Fluoride release showed a progressive and significant decrease over time (-p-value<0.001), although the amount of Fluoride released was significantly greater in the Equia Forte group compared to the Activa Bioactive group (-p-value<0.05). ConclusionsActiva Bioactive Restorative with adhesive and a nanocomposite showed similar bond strengths. Activa Bioactive Restorative doesn’t have the self-adhesive property. The fluoride ion release profile of Activa was lower than that of the Equia Forte. Key words:Bioactive composite, nanocomposite, glass ionomer, fluoride release, shear bond strength, thermocycling.

Analysis of the Fluoride Levels of Well Water Consumed by the Moroccan Population in Different Rural Areas

Fluoride plays an essential role in preventing cavities when consumed in small amounts. However, continuous excessive fluoride ingestion could cause significant adverse health effects in humans, ranging from mild dental fluorosis to debilitating skeletal fluorosis, depending on the level and period of exposure to fluorides. In rural areas, the source of fluoride in well water could be due to natural, industrial, or anthropogenic contamination. The purpose of our work was to assess the degree of contamination of groundwater by fluorides from different regions in Morocco located in agricultural campaigns, where the only source of consumable water is well water. A total of 40 well water samples were collected from 7 rural Moroccan areas. Fluoride level analyses were performed using a fluoride-specific ion electrode (HI-4110). The fluoride levels found in the various well waters of the different regions range from 0.2 mg/l to 6.58 mg/l. Five wells have levels that exceed the recommended adult standards, while 28 wells have levels above the recommended standards for children. These results help warn the public about the risk of developing dental fluorosis and encourage them to change the sources of water consumption from the well waters with high fluoride content.

Concentración de fluoruros en la sal de uso doméstico comercializada en Montevideo, Uruguay

Objectives: The aim of this study was to evaluate the concentration of fluoride (F) in household salt marketed in Montevideo, Uruguay. Methods: Fourteen household salt brands marketed in Montevideo, Uruguay were analyzed to determine the F concentrations. Salt samples were prepared and F concentrations were determined using a fluoride-specific electrode connected to an ion analyzer.Results: Most of the salt brands showed values lower than 250 mgF/kg. Coarse salt samples showed higher F concentrations compared to the refined salt samples (p &lt; 0.05). Salt brands contained sodium fluoride presented higher F concentrations than salt brands contained potassium fluoride (p &lt; 0.05). Only two brands had F concentrations close to that informed in product packages. Conclusions: Household salt brands marketed in Montevideo (Uruguay) present a great variability in their F concentrations.

Soluble Fluoride in Na2FPO3/CaCO3-Based Toothpaste as an Indicator of Systemically Bioavailable Fluoride

Fluoride chemically soluble in toothpaste is an indicator of fluoride bioavailability when the teeth are brushed, and the same should be expected systemically when toothpaste is ingested. A 4-phases study was conducted, in which 8 participants were subjected in each phase to one of the assigned treatment groups: group I: fresh sample of a Na₂FPO₃/CaCO₃ toothpaste with 1,334 μg F/g of total soluble fluoride (TSF) and groups II–IV: aged samples of toothpaste presenting TSF concentrations of 1,128, 808, and 687 μg F/g, respectively. In all phases, the participants ingested an amount of toothpaste equivalent to 70.0 μg F/kg body weight, as total fluoride (TF). Blood was collected before (baseline) and up to 180 min after toothpaste ingestion as indicator of fluoride bioavailability. Total urine (24 h before and 24 h after ingestion) was collected as indicator of absorbed fluoride that was excreted. F concentration in blood plasma and urine was determined with a fluoride ion-specific electrode. The areas under the curve (AUC) of F concentration versus time (AUC = ng F/mL × min) and the peaks of fluoride concentration in blood plasma (C_max) were calculated. The net amount of fluoride excreted (mg/day) was calculated by subtraction. A significant correlation of the amount (mg) of TSF ingested was found between the AUC (r = 0.76; p < 0.01) and C_max (r = 0.86; p < 0.01) in plasma, and the fluoride excreted (r = 0.65; p < 0.01). For TF, no statistical correlations were found (p > 0.05). Data suggest that the concentration of TSF found in Na₂FPO₃/CaCO₃-based toothpastes is a useful predictor of how much fluoride will be systemically bioavailable when this type of formulation is ingested.

Effect of brushing on surface roughness, fluoride release, and biofilm formation with different tooth-colored materials

Background/purposeTooth brushing, material mechanical ageing procedure, is the most effective way in removing biofilm. The purpose of this study was to investigate the surface roughness, fluoride-release, and S. mutans biofilm formation on various tooth-colored restorative materials before and after brushing. Materials and methodsDiscs of materials, a nanocomposite (Filtek Z350XT; CO), a giomer (Beautifil II; GIOMER), a resin-modified glass-ionomer material (Fuji II LC; RMGI), and a conventional glass-ionomer material (Fuji IX GP Extra; GI), were prepared, polished with abrasive discs (SofLex), and divided into brushed and not brushed groups. The surface roughness of specimens was observed using a contact profilometer, fluoride-release was measured using a fluoride-specific ion electrode, and S. mutans biofilm formation, biovolume and live/dead cells, was observed under a confocal laser scanning microscope. ResultsHigher roughness was observed on GI and RMGI than on CO and GIOMER. Brushing had no effect on the roughness. The fluoride-release of GI and RMGI was higher than that of GIOMER. The fluoride-release decreased after brushing in all materials. The biovolume of S. mutans was not significantly different between GIOMER, RMGI and GI, while CO showed the highest. Brushing resulted in a higher biovolume for all materials, except CO, which showed no change. After brushing, all the tested materials demonstrated identical biovolumes. There were no significant differences in live/dead cells among all groups. ConclusionBrushing demonstrated a negative effect on the fluoride-release and biovolume of S. mutans biofilms for all tested materials except nanocomposites.

An in vitro Comparative Evaluation of Fluoride Uptake by Demineralized Enamel Exposed to Four Different Low Fluoride Dentifrices

Background: Topical fluoride application has an important role in caries prevention. The aim of the present study was to evaluate and compare fluoride uptake of tooth enamel after exposure to four commercially available low fluoridated toothpastes. Methods: The present in vitro study was conducted on 60 sound extracted premolar teeth. The teeth were covered with acid-resistance nail polish except at a 5×5 mm area on the buccal and lingual surface of each tooth (for experimental and control group respectively). After demineralization of the window area for 2 days, the teeth were immersed in toothpaste slurry containing: Sodium Fluoride 1000ppm (Group A), Soduim monofluorophosphate 1000ppm (Group B), Soduim monofluorophosphate 500ppm (Group C) and Sodium fluoride 500ppm (Group D). The pH of the dentifrices was measured. The acid biopsy technique and fluoride ion-specific electrode was used for fluoride ion estimation. Results: All of the applied toothpastes significantly increased fluoride content of the enamel compared with the control group (P <0.001). There was a significant difference among the four groups of toothpastes in the mean fluoride uptake and group A showed maximum uptake of fluoride (5.5920 ppm), followed by group B, C and D respectively. According to Pearson correlation analysis, there was not any significant relationship between the pH of the dentifrices and uptake of fluoride. Conclusion: There was a positive correlation between the fluoride concentration of dentifrices and the fluoride uptake on demineralized enamel. The toothpastes containing NaF are more effective than toothpastes containing NaMFP. Moreover, dentifrice pH had no influence on fluoride uptake by enamel.

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

BackgroundBottled water has become the most consumed beverage in the United States. The authors aimed to inform the dental profession about the potential anticaries benefits of some bottled waters and to provide information about their possible contributions to fluoride, calcium, magnesium, sodium, and potassium intakes. MethodsThe authors chose a convenience sample by purchasing all different bottled waters from the main supermarkets operating in Indianapolis, Indiana. The authors analyzed the fluoride content using a fluoride ion–specific electrode and metal concentrations using atomic absorption spectroscopy. They used dietary reference intakes to calculate hypothetical intakes of all minerals. ResultsThe authors identified 92 different bottled waters. Fluoride concentrations were generally low (mean, 0.11 parts per million [ppm]; median, 0.04 ppm). Only 2 waters contained more than 0.7 ppm fluoride (0.95 ppm and 1.22 ppm). Metal concentrations varied considerably among waters. Calcium concentrations ranged from less than 0.1 through 360 ppm (mean, 26.9 ppm; median, 5.2 ppm), which were greater than those of magnesium (range, < 0.01-106 ppm; mean, 7.5 ppm; median, 1.9 ppm), sodium (range, < 0.01-109 ppm; mean, 11.1 ppm; median, 2.9 ppm), and potassium (range, < 0.01-43 ppm; mean, 3.6 ppm; median, 1.2 ppm). Overall, most bottled waters do not contribute to adequate intakes of fluoride, potassium, or sodium or to recommended dietary allowances for calcium and magnesium. Nonetheless, some waters can provide meaningful contributions to fluoride, calcium, and magnesium intake. ConclusionsThe fluoride concentration in 90 of the 92 studied bottled waters is insufficient to contribute to caries prevention. Only a few bottled waters can be considered health-promoting. Practical ImplicationsDental professionals should consider the mineral content of water consumed by their patients during caries risk assessment.