Fluoride Group Research Articles

Economic evaluation of a water fluoridation scheme in Cumbria, UK.

The addition of fluoride to community drinking water supplies has been a long-standing public health intervention to improve dental health. However, the evidence of cost-effectiveness in the UK currently lacks a contemporary focus, being limited to a period with higher incidence of caries. A water fluoridation scheme in West Cumbria, United Kingdom, provided a unique opportunity to study the contemporary impact of water fluoridation. This study evaluates the cost-effectiveness of water fluoridation over a 5-6 years follow-up period in two distinct cohorts: children exposed to water fluoridation in utero and those exposed from the age of 5. Cost-effectiveness was summarized employing incremental cost-effectiveness ratios (ICER, cost per quality adjusted life year (QALY) gained). Costs included those from the National Health Service (NHS) and local authority perspective, encompassing capital and running costs of water fluoridation, as well as NHS dental activity. The measure of health benefit was the QALY, with utility determined using the Child Health Utility 9-Dimension questionnaire. To account for uncertainty, estimates of net cost and outcomes were bootstrapped (10 000 bootstraps) to generate cost-effectiveness acceptability curves and sensitivity analysis performed with alternative specifications. There were 306 participants in the birth cohort (189 and 117 in the non-fluoridated and fluoridated groups, respectively) and 271 in the older school cohort (159 and 112, respectively). In both cohorts, there was evidence of small gains in QALYs for the fluoridated group compared to the non-fluoridated group and reductions in NHS dental service cost that exceeded the cost of fluoridation. For both cohorts and across all sensitivity analyses, there were high probabilities (>62%) of water fluoridation being cost-effective with a willingness to pay threshold of £20 000 per QALY. This analysis provides current economic evidence that water fluoridation is likely to be cost-effective. The findings contribute valuable contemporary evidence in support of the economic viability of water fluoridation scheme.

Remineralization potential of dentifrices with calcium sodium phosphosilicate and functionalized tri-calcium phosphate in the deeper incipient carious lesions: An in vitro study.

This study evaluated the remineralization potential of calcium sodium phosphosilicate and functionalized tri-calcium phosphate (f-TCP) dentifrices in deeper incipient carious lesions (ICLs). Artificial ICLs were created by placing premolars into demineralizing solutions. Teeth were randomly assigned into four groups: calcium sodium phosphosilicate (Group 1), f-TCP (Group 2), 1450 ppm fluoride (Group 3), and distilled water (Group 4), which were subjected to 10-daypH cycling. Mineral density (MD) was assessed using microcomputed tomography (Micro-CT), while hardness (H) and elastic modulus (EM) were assessed using nanomechanical testing. MD % gain was higher in Groups 1-3 than in Group 4. In addition, Groups 1 and 2 exhibited significantly higher MD % gain than Group 3. Also, Groups 1-3 showed significantly higher EM and H values than Group 4 in the outer enamel area; yet, Groups 1 and 2 displayed significantly higher EM and H values than Groups 3 and 4 in the inner enamel. The MD, EM, and H of ICLs significantly increased with the addition of calcium sodium phosphosilicate or f-TCP to fluoridated dentifrices compared to standard fluoride dentifrices. The added active ingredients remineralized the deeper parts of the ICLs, while remineralization at the lesion surface was similar between tested dentifrices.

The Effect of Green Tea Varnish in Comparison with Fluoride Varnish on Remineralization of Artificial Caries

Introduction: Green tea is a natural herb, that has catechin, theanine and amino acids with antioxidant, anti-inflammatory, antimicrobial and anti-mutagenic properties that can improve the salivary parameters and consequently protect the oral cavity from diseases. So, the study aimed to investigate the effect of green tea varnish on remineralization of artificial caries and compare its effect with fluoride varnish. Materials and Methods: 30 extracted sound teeth were kept in demineralizing solution for 4 days, to artificially form caries-like lesions. The teeth were divided equally and randomly into three groups. Group 1 was treated with green tea varnish, group 2 was treated with sodium fluoride varnish, and group 3 left without treatment. After treatment pH cycling was done. Results: The mean Ca weight% of green tea and fluoride varnish groups (36.85 ± 0.59 and 37.51 ± 0.65 respectively) were significantly higher than the control group (26.98 ± 0.24). Also, the mean p weight% was found to be significantly higher in the green tea group (17.50 ± 0.36) and fluoride group (18.31 ± 0.40) versus the control group (13.91 ± 0.15). Conclusions: Green tea varnish had the same remineralizing effect as Fluoride varnish. Recommendations: More studies are required using other concentrations of green tea varnish and may use more than one application, and in vivo studies need to be done.

In Vitro Evaluation of Remineralization Potential: Whey Extract, Fluoride Varnish, and Fluoride Mouthwash on Bleached Enamel

Background: Extrinsic discoloration is treated with bleaching which increases enamel porosity and roughness. Remineralizing materials is applied to avoid the bleaching side effects. The current study aimed to evaluate time dependent safety of bleaching materials on enamel surfaces roughness, and to assess the remineralizing potential of whey extract as a natural product and to compare it with the commercially available fluoride varnish and fluoride mouthwash after maximum bleaching time (30 min.). Methods: Extracted human incisor teeth without cracks or any enamel defects were used in this study. Teeth were cleaned and decoronated at the level of the cementoenamel junction. A nail varnish was used to cover the entire surface of the crowns of each tooth, leaving a window measuring 4 mm × 4mm. Bleaching material was applied to the enamel of all teeth specimens. The Application of bleaching material was repeated 2 more times, each time for 10 minutes, which amounted in total to 30 min. The specimens in group 1 were soaked in artificial saliva, the specimens in group 2 were soaked in whey extract, the specimens in group 3 were treated with fluoride varnish and group 4 specimens were soaked in fluoride mouthwash. Results: The mean value of the surface roughness of all the teeth specimens was increased significantly after bleaching for 10 minutes, 20 minutes and 30 minutes (p=0.000) when compared with baseline mean value. As well, there was significant direct correlation between application time of bleaching material and mean value of surface roughness (r= 0.94). There were no significant differences (p>0.05) between the specimens of the 4 groups when the mean value of surface roughness compared at baseline and after bleaching. But, after treatment, there was significant difference (p≤0.05) between the 4 groups, with the best result obtained from whey extract and fluoride varnish. Conclusions: The enamel surface roughness is significantly and directly correlated with prolonged application time of bleaching material. Remineralizing materials; whey extract, fluoride varnish and fluoride mouth wash had significantly decreased enamel surface roughness caused by bleaching. Whey extract has statistically the same effect as fluoride varnish on decreasing the surface roughness of bleached enamel surface.

Desensitizing agents’ post-bleaching effect on orthodontic bracket bond strength

Background: Nowadays, many patients wanting to bleach and do orthodontic treatment simultaneously, in-office bleaching is more favorable because of the instant results. However, in-office bleaching procedures result in severe enamel surface demineralization and decreasing the attachment of the orthodontic bracket. Applying a desensitizing agent after in-office bleaching can remineralize the enamel surface. There are two types of desensitizing agents: Fluoride-based and non-fluoride-based. Purpose: This study aims to analyze the effect of applying fluoride-based and non-fluoride-based desensitizing agents after in-office bleaching on orthodontic brackets. Methods: Twenty-seven post-extraction upper premolars were divided into three groups (n=9): Control group, fluoride-based group, and non-fluoride-based group. The samples were subjected to an in-office bleaching procedure before a fluoride desensitizing agent was applied to the fluoride group and a non-fluoride desensitizing agent was applied to the non-fluoride group. Then, a brackets bonding procedure was performed on all samples. The samples were tested for shear bond strength (SBS), and the adhesive remnant index (ARI) was measured. The data was analyzed by a one-way analysis of variance on the SBS test, while the ARI scores were analyzed by the Kruskal–Wallis test. Results: The fluoride and non-fluoride groups showed a significantly increased SBS of the brackets after in-office bleaching (P < 0.05), with the fluoride-based desensitizing agent having the highest SBS score, while the ARI scores had an insignificant difference between all groups (P > 0.05). Conclusion: The application of desensitizing agents after in-office bleaching increased the metal brackets' SBS but could not change the ARI scores.

The antimicrobial activity of theobromine against cariogenic microbes: an in vitro pilot study

ObjectiveThis pilot study aimed to compare the antimicrobial effect of theobromine, sodium fluoride, and a theobromine-sodium fluoride combination against the following caries-associated bacteria: Streptococcus mutans and Actinomyces naeslundii.MethodologyAntimicrobial susceptibility was tested via the broth microdilution method, with suspensions cultured on each microbe’s respective selective media. Shapiro–Wilk’s was completed and all the data showed normality (p > 0.05), and One-way ANOVA was applied to infer the significant differences in the viable counts between the groups.ResultsAll experimental conditions for both S. mutans and A. naeslundii groups resulted in a significantly lower bacterial abundance in comparison to the control medium, without any active antimicrobial agent (p < 0.001). There was no significant difference in viable count between the theobromine, fluoride, or combination groups against either microbe (p > 0.05).ConclusionTheobromine’s antimicrobial activity against S. mutans and A. naeslundii was found similar to that of fluoride, whether used independently or in combination. Further testing of theobromine is necessary to assess its role as an alternative anticaries agent.

A review of water fluoridation studies and the effect on dental caries and treatment costs, undertaken in Scotland.

Objectives This review aimed to investigate the effect of water fluoridation on the dental health of Scottish people by comparing results of starting and discontinuing fluoridation in Scotland.Data sources Data sources were retrieved from electronic databases. The grey literature was also searched. Articles were selected if the population of interest was Scottish. The objective was to evaluate the influence of water fluoridation on dental caries using the dmft/s, DMFT/S (decayed, missing and filled teeth/surfaces) or deft/s indices (decayed, extraction needed, filled teeth/surfaces).Data extraction Name of the authors, publication years, location of the study, sample size, type of study design, age of participants, method of assessing the outcome, data related to the exposure and the outcome, and the overall result of each study were extracted. The data were collected based on the effect of water fluoridation and its cessation on dental caries and the type of dentition.Results Nine studies were included in the review. The findings revealed that the introduction of water fluoridation led to reductions in caries. Moreover, after the cessation of fluoridation, caries levels continued to remain lower in the fluoridated groups. Additionally, fluoridation had the effect of reducing the cost of dental treatment.Conclusion Water fluoridation was effective in improving dental caries among the Scottish child population. New studies are required to provide contemporary evidence for water fluoridation in Scotland.

Exercise Alleviates Fluoride-Induced Learning and Memory Impairment in Mice: Role of miR-206-3p and PREG.

Fluorosis decreases the learning and memory ability in humans and animals, while exercise can reduce the risk of cognitive decline. However, the effect of exercise on learning and memory in fluoride-exposed mice is unclear. For this purpose, in this study, mice were randomly allotted into four groups (16 mice per group, half male and half female): control group (group C), fluoride group (group F, 100mg/L sodium fluoride (NaF)), exercise group (group E, treadmill exercise), and E plus F group (group EF, treadmill exercise, and 100mg/L NaF). During 6months of exposure, exercise alleviated the NaF-induced decline in memory and learning. In addition, NaF induced injuries in mitochondria and myelin sheath ultrastructure and reduced the neurons number, while exercise restored them. Metabolomics results showed that phosphatidylethanolamine, pregnenolone (PREG), and lysophosphatidic acid (LysoPA) were altered among groups C, F, and EF. Combined with previous studies, it can be suggested that PREG might be a biomarker in response to exercise-relieving fluorine neurotoxicity. The miRNA sequencing results indicated that in the differently expressed miRNAs (DEmiRNAs), miR-206-3p, miR-96-5p, and miR-144-3p were shared in groups C, F, and EF. After the QRT-PCR validation and in vitro experiments, it was proved that miR-206-3p could reduce cell death and regulate AP-1 transcription factor subunit (JunD) and histone deacetylase 4 (HDAC4) to alleviate fluoride neurotoxicity. To sum up, the current study reveals that exercise could alleviate NaF-induced neurotoxicity by targeting miR-206-3p or PREG, which will contribute to revealing the pathogenesis and therapeutic method of fluoride neurotoxicity.

Study on the occurrence state of main components of phosphogypsum dihydrate and its impurity distribution.

The dihydrate phosphoric acid process is the mainstream technique. However, the phosphogypsum (PG) produced contains high levels of impurities such as phosphorus and fluorine, severely constraining its valorization. In order to elucidate the occurrence patterns of phosphorus and fluorine impurities in PG, this study employed analytical methods including XRF, XRD, AMICS (Automated Mineralogy Integrated with Chemistry System), XPS, and chemical element balance analysis. We investigated the occurrence states of phosphorus, fluorine, silicon, iron, and aluminum elements in PG from wet-process phosphoric acid production, as well as the distribution characteristics of phosphorus and fluorine impurities. Additionally, we utilized Density Functional Theory (DFT) calculations to determine the binding energies of major minerals with water-soluble phosphate and fluoride groups, and analyzed the zeta potentials of gypsum and quartz mineral surfaces. The results indicate that the main mineral phases in PG are gypsum, quartz, potassium silicate minerals, aluminosilicate minerals, and hematite, predominantly occurring in monomineralic forms. Phosphorus impurities primarily exist in calcium silicate and hematite minerals, while fluorine is mainly associated with gypsum and potassium silicate minerals. DFT calculations demonstrate strong binding energies between calcium silicate and hematite minerals with PO4 3-, as well as between gypsum and quartz minerals with F-. The acidic conditions in the separation tank during wet-process phosphoric acid production may contribute to the distinctive distribution characteristics of phosphorus and fluorine impurities in PG.

Efficacy of Silver Diamine Fluoride in Arresting Dental Caries in Primary Teeth in Patient Visiting Tertiary Hospital of Kathmandu

IntroductionCarious lesions can both be prevented and arrested using fluoride-based materials. This study was done to evaluate and compare the efficacy of silver diamine fluoride in arresting dental caries at different frequencies of applications. MethodsThis experimental study was conducted among ten preschool children of 3-5 years old with seventy-four active carious lesions taking teeth as a sample unit. Children were randomly allocated into two intervention groups: Group 1— application of 38% silver diamine fluoride solution atthree consecutive weeks and Group 2— three applications of 38% silver diamine fluoride solution at monthly interval. The time taken of caries arrest was recorded. Data were collected and entered in Microsoft Excel sheet and analysis was done in Statistical Package for the Social Sciences (SPSS) version 16. ResultsThe mean time taken for caries arrest for Group II (57.20 days) was found to be statistically longer than Group I (21.54 days) (p-value &lt; 0.001). As the mean time taken for caries arrest for Group I was shorter, the weekly application was found to have higher efficacy than the monthly application. ConclusionsEfficacy of Silver Diamine Fluoride was found to be more in Group I (weekly application) compared to Group II (monthly application).

Periploca forrestii Schltr. ameliorate liver injury caused by fluorosis in rat

To investigate the impact of the ethanoic fractions of Periploca forrestii Schltr. (P. forrestii) in ameliorating the liver injury caused by fluoride ingestion and to explore the potential mechanisms. Initially, an in vitro fluorosis cell model was constructed using the human normal liver cell line (L-02) induced by fluoride. Cell viability was assessed using the CCK-8 assay kit. The lactate dehydrogenase (LDH) assay kit was utilized to measure LDH content in the cell supernatant, while the malonic dialdehyde (MDA) assay kit was employed to determine MDA levels within the cells. Subsequently, a fluorosis rat model was established, and LDH content in the cell supernatant was measured using the LDH assay kit. Various parameters, including MDA, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and reactive oxygen species (ROS) content within the cells, were detected using appropriate assay kits. Additionally, cell apoptosis rate was determined using the Annexin V-FITC/PI cell apoptosis assay kit. The protein expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), Caspase-3, Cleaved Caspase-3, Caspase-9, and Cleaved Caspase-9 were analyzed through Western blotting. Compared to the model group, the ethanolic fraction D of P.forrestii (Fr.D) increased cell viability (P < 0.01) and decreased LDH and MDA levels (P < 0.01). In the high-dose Fr.D treatment group of fluoride-poisoned rats, serum ALT, AST, LDH and MDA levels significantly decreased (P < 0.01). Results from rat primary cells exhibited that the Fr.D administration group exhibited significantly higher cell survival rates than the fluoride group (P < 0.01). Similarly, primary rat cells treated with Fr.D showed enhanced cell viability (P < 0.05) and reduced apoptosis rate, LDH, MDA, SOD, GSH-Px, CAT, and ROS levels (P < 0.05) compared to the model group. Western blot analysis indicated that the Fr.D treatment group elevated the Bcl-2/Bax protein expression ratio and reduced Caspase-3 and Caspase-9 activation levels (P < 0.01) compared to the model group. The results suggest that components within the Fr.D from Periploca forrestii may alleviate fluoride-induced liver injury by potentially counteracting oxidative stress and cell apoptosis.

FSO2 Radical-Initiated Photoredox Cyclization of 4-Enoic Acids to Functionalized γ-Lactones

AbstractThe incorporation of sulfonyl fluoride groups into molecules has been proven effective in enhancing their biological activities or introducing new functions. Herein, a transition-metal-free and visible-light-mediated radical tandem cyclization of unsaturated carboxylic acid is reported. This affords a facile access to FSO2-functionalized γ-lactones efficiently, which are critical structural motifs widely present in biologically active molecules.

The functional electrolyte containing 2-fluorobenzenesulfonyl fluoride (2FF) additive enhances the performance of LiNi0.8Co0.1Mn0.1O2/graphite batteries by stabilizing the cathode interface

A functional electrolyte containing conventional carbonate esters solvents, LiPF6 salt, and novel 2-fluorobenzenesulfonyl fluoride (2FF) additive is developed to stabilize the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode interface and enhance the performance of NCM811/graphite lithium-ion batteries (LIBs). It is indicated that due to the unique C-F and sulfonyl fluoride groups of 2FF, the NCM811/Li half batteries containing 2% 2FF electrolyte show the highest cycling performance, a coulombic efficiency of 98.4% and a capacity retention of 89.4% are obtained after 100 cycles at 0.5C. And compared to the pouch NCM811/graphite full batteries with blank electrolyte, the long cycle performance of the batteries with 2% 2FF is also increased after 500 cycles at 45 °C, the discharge capacity retention rate retains at 80.04% and the coulombic efficiency closes to 100%. The spectroscopic characterization and theoretical calculation demonstrate that the electrolyte with 2FF additive preferentially react and generate uniform CEI film. These results show that this 2FF-containing electrolyte can stabilize NCM811 cathode interface, revealing a promising prospect of the commercial application of high-nickel LIBs.

Influence of Different Mouthwashes on the Efficacy of Fluoridated Dentifrices in Prevention of Enamel Erosion: An In Vitro Study.

The purpose of the current study was to evaluate the impact of three various mouthwashes on the effectiveness of fluoride dentifrices in preventing enamel erosion. A total of 120 sound intact human premolar teeth which were extracted for orthodontic treatment were selected for the study. A 3 × 3 mm window section was positioned in the middle of the coronal surface of the tooth in order to define the study area. Each sample was placed in a solution of 1% citric acid (pH 3.5) for 10 minutes in order to produce an eroded surface. All samples were divided into two main groups (60 samples each) as follows: Group A for sodium fluoride dentifrices and group B for stannous fluoride dentifrices, again it is subdivided into: CHX: Chlohex ADS®, EO: Listerine®, CPC: Colgate® Plax (20 samples in each subgroup). After that, samples underwent the pH cycling model for 5 days. Samples were examined for surface loss using a scanning electron microscope. In sodium fluoride dentifrices group, before intervention, the surface loss was 3.12 ± 1.03 in CHX group, 3.08 ± 1.20 in EO group, and 3.09 ± 0.96 in CPC group. After intervention, the less surface loss found with CHX group (2.18 ± 0.84), followed by CPC (2.34 ± 0.74) and EO group (2.46 ± 0.97). In stannous fluoride dentifrices group, before intervention, the surface loss in CHX group was 3.26 ± 1.19, in EO group, it was 3.18 ± 1.31, and in CPC group, it was 3.22 ± 1.06. After intervention, the less surface loss found with CHX: group (1.90 ± 0.54), followed by CPC (2.24 ± 0.28) and EO group (2.38 ± 0.20). The present study concluded that the fluoride dentifrices' preventive effects against tooth surface loss were unaffected by a different mouthwashes with varying compositions and major constituents. In terms of erosion, fluoridated toothpaste containing stannous fluoride was found to provide better surface loss protection than sodium fluoride. Primary prevention and the eradication of contributing causes are the greatest strategies for preventing erosion. Simultaneously, antibacterial agent in the mouthwashes may help in enhancing the effect of fluoride in the enamel, owing to their high affinity for teeth structures. Therefore, in addition to cause-related treatment, further efforts to reduce tooth tissue loss are also necessary.

Does Dactyloctenium aegyptium ethanolic extract protect against hormonal, histological and immunohistochemical alterations induced by sodium fluoride in rat adrenal gland?

ABSTRACT This work aimed to perform a biochemical, histological, and immunohistochemical assessment of the influence of sodium fluoride on the adrenal gland of rats and the possible ameliorating role of Dactyloctenium aegyptium (D. aegyptium). Thirty-five male albino rats were divided into five equal groups: group I served as the control group, group II received sodium fluoride (5 mg/kg), group III received D. aegyptium (200 mg/kg), and groups IV and V received sodium fluoride and D. aegyptium (100 and 200 mg/kg respectively) simultaneously for 28 days. Aldosterone, corticosterone, nitric oxide, sodium, potassium, and chloride were measured in serum samples. Adrenal gland specimens were processed for histological, histochemical, and immunohistochemical studies. The sodium fluoride group recorded a significant reduction in serum levels of aldosterone, corticosterone, potassium, and chloride (p ≤ 0.0001) and a significant increase in nitric oxide (p ≤ 0.0001) and serum sodium (p = 0.0076) when compared with the control group. Histological changes in the sodium fluoride treated group showed cytoplasmic vacuolation, scattered apoptotic cells, and hemorrhage. The sodium fluoride treatment significantly decreased glycogen (p = 0.0002), total protein) p = 0.0007), and DNA (p ≤ 0.0001) and increased inducible nitric oxide synthase (p = 0.0001). Co-treated groups with D. aegyptium showed almost average values for most parameters and a nearly standard architecture. The present data answers the question of our research that D. aegyptium ethanolic extract could protect against sodium fluoride’s adverse effects in rat adrenal glands on the physiological and histological levels.

Optically Anisotropic Mixed-Metal Fluoroiodate Ba2[GaF5(IO3F)] with a Wide Optical Transparent Window and a Moderate Birefringence.

An optically anisotropic alkali-earth-metal gallium fluoroiodate, Ba2[GaF5(IO3F)] (1), was ingeniously obtained by integrating fluoride and fluoroiodate functional units under moderate hydrothermal conditions. It features a three-dimensional (3D) structure constructed by the highly polarizable fluoroiodate unit [IO3F] and the fluoride groups [GaOF5] and [BaO3Fx] (x = 6, 7). The compound is stable at temperatures up to 500 °C. With the synergistic interaction between [IO3F] and the fluoride groups, the mixed-metal fluoroiodate induces a short ultraviolet cutoff edge at about 230 nm, a medium measured birefringence of 0.068 @ 550 nm, and a wide optical transparent window (0.34-11.9 μm), indicating that 1 has potential applications as a birefringent material from near-UV to mid-infrared. Theoretical calculations prove that the optical characteristics of the compound are mainly attributed to [IO3F] and the fluoride functional groups. This work demonstrates that the presence of various specific functional groups in compounds will help to develop promising inorganic functional materials possessing good optical performance.

The potential of galactomannan from Caesalpinia ferrea on erosive dentin wear reduction in vitro.

Gels containing juca seed galactomannan (JSG) were evaluated for their potential to prevent the progression of dentin erosive wear in an in vitro study with four experimental groups (n = 9). The treatments included distilled water (DW), 0.05% stannous fluoride (121 ppm F), and 0.5% or 1% JSG. The specimens underwent a cycle (3 times/day) consisting of immersion in 1% citric acid (5 minutes), treatment (5 minutes), and artificial saliva exposure (2 hours/overnight) for 5 days. Surface changes were assessed using mechanical profilometry (wear), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The data were analyzed using ANOVA followed by Tukey's post-test (p < 0.05). The negative control group exhibited the highest wear (6.0 µm ± 3.5), significantly differing from the group treated with 0.05% stannous fluoride gel (p = 0.007), which showed less dentin loss. The groups treated with 0.5% and 1% JSG showed results similar to the negative control (p = 0.661; p = 0.212, respectively) and the stannous fluoride group (p = 0.103; p = 0.379, respectively). In the SEM images, the specimen treated with stannous fluoride showed obliterated tubules, while the JSG gels formed crystals on the dentin surface, as confirmed by the presence of oxygen and calcium in the EDS analysis. Although the JSG gels showed similar results to the stannous fluoride, did not exhibit superior efficacy at the tested concentrations.

In ovo exposure of F-ions and organo-fluoride insecticide (Bifenthrin) cause developmental anomalies of eye in chick embryos

ObjectiveThe developmental abnormalities of the in-ovo exposure of Fluoride ions (F-ions) and Bifenthrin (BF) on the embryonic chick eye were investigated. Materials and methods165 fresh fertilized eggs of zero day and 40–50 g weight were divided into three groups (55 eggs each) on the basis of inter-vitelline treatment of eggs on zero day of study: 1) Control group (CG); 0.1 ml of 5 % DMSO aqueous solution 2),3) Fluoride group (FG), and Bifenthrin group (BFG); 0.01 mg/kg F-ions (from NaF) and 0.01 mg/kg BF in 0.1 ml of 5 % DMSO aqueous solution respectively. After incubation for 14 days at 37 ± 0.5 °C embryos were externalized. Eyes of each embryo were removed for micro-anatomical, micrometric and histopathological studies. ResultsThe histological sections have shown denser and enlarged marginal mitotic region of the developing eye lenses in FG and BFG. In vertical sections of the eye lenses the nuclei of the crystalline cells in FG and BFG show a highly depressed bow shaped arrangement. Moreover, the nuclei of the core crystalline cells of the lens were apparently smaller in FG and BFG than CG. Out of the six anatomical layers of the retina the nuclear and the plexiform layers were highly enlarged in FG and BFG, similarly the three corneal cell layers (endothelial, parenchymal and epithelial) were enlarged in FG and BFG than CG. The morphometric, histometric and micrometric estimations also show significant variations in FG and BFG than CG. ConclusionThe results indicate subtle developmental anomalies of the eyes attributable to the F-ions and BF exposure indicating their developmental neuro-optic disruption potentials. Results further revealed higher toxicity of BF as compared to F-ions.

Effects of sodium fluoride on neural tube development in chick embryos

ObjectiveVarious environmental factors encountered in daily life are associated with the development of neural tube defects. This study aims to investigate the effects of fluoride on neural tube development in chick embryos. MethodsA total of 60 specific pathogen-free, fertile, zero-day Leghorn-type eggs were used in the study. Group 1 was the control group, in which only saline was administered. Group 2 was the low-dose group, in which 0.003 mg of fluoride was administered, and Group 3 was the high-dose group, in which 0.006 mg of fluoride was administered. After 72 h of incubation, the embryonic disc was evaluated microscopically. ResultsIn the control group, the surface ectoderm of all sections was intact, the neural tube was closed, and the neuroepithelium, the basement membrane surrounding the neuroepithelium, the somites, and the notochord displayed standard structure. Neural tube defects were observed in 3 of the chick embryos, that was given low-dose fluoride. In Group 3, which was administered high doses of fluoride, neural tube defects were observed in 4 embryos. It was observed that the development of neural tube defects was no statistically significantly higher in low and high-dose fluoride group compared to the control group. ConclusionLow and high-dose fluoride exposure was associated with developing neural tube defects, but there was no statisticaly significance.

Fabrication of ionic liquid-functionalized aliphatic polycarbonate brushes for self-polishing antibacterial application

To meet the development of multifunctional surfaces with long-term antibacterial activity for biomaterials and implantable devices, herein, a novel self-polishing antibacterial surface was developed. The functionalized surface was prepared by first surface-initiated ring-opening grafting polymerization (SI-ROP) of a cyclic carbonate monomer 4′-(fluorosulfonyl)benzyl-5-methyl-2-oxo-1,3-dioxane-5-carboxylate (FMC) containing a sulfonyl fluoride group in the side chain onto the material surface and then by a “sulfur(IV)-fluorine” exchange (SuFEx) postclick modification reaction to link the imidazolium salt ionic liquid to the polyFMC (PFMC) brush. In vitro experimental results showed that the functionalized surface has good biocompatibility, enzymatic biodegradable properties and excellent bactericidal properties, which can effectively kill E. coli (∼94%) and S. aureus (∼93%). In addition, the functionalized surface can release the killed bacteria (∼90%) several times efficiently under the action of lipase enzymatic degradation, restoring the original bactericidal function of the surface, thus forming a dynamic self-polishing and self-renewing antibacterial surface. Therefore, this method for the fabrication of self-polishing antibacterial surfaces may offer innovative insights into applications of biomedical implant materials.