Study on the mechanical and aging properties of an antibacterial composite resin loaded with fluoride-doped nano-zirconia fillers.

Preventing the occurrence of secondary caries serves as one of the significant issues in dental clinic, thus make it indispensable to improving the properties of conventional composite resin (CR) by developing a novel CR. In present study, two groups of experimental CRs loaded with different contents of fluoride-doped nano-zirconia fillers (25 wt% and 50 wt%) were fabricated. The surface topography, mechanical performance, fluoride release, antibacterial effect, aging property and cytotoxicity of the experimental CRs were evaluated subsequently. A uniform distribution of the F-zirconia fillers over the whole surface of resin matrix could be observed. The experimental CRs showed continuous fluoride release within 28 days, which was positively correlated with the content of F-zirconia fillers. Moreover, the amount of fluoride release increased in the acidic buffer. Addition of F-zirconia fillers could improve the color stability, wear resistance and microhardness of the experimental CRs, without reducing the flexure strength. Furtherly, the fluoride ions released continuously from the experimental CRs resulted in effective contact and antibacterial properties, while they showed no cytotoxicity. As a consequence, considerations can be made to employ this new kind of composite resin loaded with fluoride-doped nano-zirconia fillers to meet clinical requirements when the antimicrobial benefits are desired.

Voltage-Driven Fluorine Motion for Novel Organic Spintronic Memristor.

Integrating tunneling magnetoresistance (TMR) effect in memristors is a long-term aspiration because it allows to realize multifunctional devices, such as multi-state memory and tunable plasticity for synaptic function. However, the reported TMR in different multiferroic tunnel junctions is limited to 100%. Here, we demonstrate a giant TMR of -266% in La0.6Sr0.4MnO3(LSMO)/poly(vinylidene fluoride)(PVDF)/Co memristor with thin organic PVDF barrier. Different from the ferroelectricity-based memristors, we discover that the voltage-driven F motion in the junction generates a huge reversible resistivity change up to 106% with ns timescale. The removing F from PVDF layer suppresses the dipole field in the tunneling barrier, thereby significantly enhances the TMR. Furthermore, the TMR can be tuned by different polarizing voltage due to the strong modification of spin-polarization at the LSMO/PVDF interface upon F doping. The combining of high TMR in the organic memristor paves the way to develop high-performance multifunctional devices for storage and neuromorphic applications. This article is protected by copyright. All rights reserved.

Knowledge of the health personnel involved in the fluoride varnish therapy programs of primary schools in Tehran, Iran.

INTRODUCTION: The World Health Organization (WHO) places great importance on oral health promotion programs in schools, given that approximately one billion people worldwide are students. This demographic not only includes the students themselves, but also extends to school staff, their families, and the broader community, all of whom are interconnected. The objectives of this study were firstly to assess the knowledge of health personnel conducting fluoride varnish treatment (FVT) in schools, and secondly to solicit their views on the effectiveness of their training methods. METHODS: Data was collected from health personnel involved in FVT in schools, supervised by medical universities in Tehran province, using a questionnaire. The questionnaire was divided into four sections: demographic information, methods of receiving FVT training, respondents' knowledge regarding FVT, and opinions about the effectiveness of FVT training methods. The questionnaire was distributed via social media, phone conversations, and email. The collected data was analyzed using Mann-Whitney in SPSS Version 26. A regression model was also fitted to the data. RESULTS: The present study included 403 participants. Among various educational methods, it was found that participation in previous workshops (P = 0.001) and FVT workshops (P = 0.013) was significantly correlated with a higher FVT knowledge score. Additionally, participation in previous oral health promotion programs was significantly associated with a higher knowledge score (P < 0.05). Therefore, a history of participating in previous health promotion programs significantly contributed to the participants' knowledge. CONCLUSION: Participation in previous oral health programs was found to be significantly correlated with a higher knowledge score. The effectiveness of training programs can be attributed to participation in previous workshops and FVT workshops. This study provided insights into potential strategies for enhancing personnel training in national oral health programs.

An In Vitro Study to Evaluate the Antimicrobial Activity of a Zinc Citrate, Sodium Fluoride, Alum and Xylitol-Based Toothpaste Formulation.

INTRODUCTION: Periodontitis is a prevalent condition significantly affecting oral health. Comorbid conditions, such as diabetes, can heighten the severity of periodontal disease and overall oral health. Therefore, to enhance oral health and manage comorbid conditions, comprehensive periodontal care is essential. This approach could involve using toothpaste containing antimicrobial ingredients in routine oral care. This paper presents the results of an in vitro study analysing the antimicrobial properties of the test formulation containing zinc citrate, alum, sodium fluoride, and xylitol-based toothpaste (Stolin-R). These ingredients work together to help in providing comprehensive oral care by controlling growth of bacteria majorly responsible for periodontal disease and thus maintaining optimal oral hygiene. AIM: To determine the antimicrobial properties of zinc citrate, alum, sodium fluoride, and xylitol-based toothpaste formulation against key periodontal pathogens through in vitro analyses. MATERIALS AND METHODS: The antimicrobial efficacy of test formulation is evaluated through minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-dependent antibacterial assessment against key periodontal pathogens, including Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia, Streptococcus mutans, and Bacteroides fragilis. RESULTS: The test formulation demonstrated potent antimicrobial effectiveness against Bacteroides fragilis, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Streptococcus mutans, and Tannerella forsythia, by exhibiting low MIC and MBC. Additionally, significant bacterial reduction, exceeding 99.99%, was observed within five minutes, emphasising its potential as an effective adjunct in combating periodontal infection. CONCLUSION: Zinc citrate, alum, sodium fluoride, and xylitol-based toothpaste formulation demonstrates significant antimicrobial activity against key periodontal pathogens, suggesting its potential as an effective agent for maintaining oral health and combating gingival infection.

Synergistic inhibition of ureolytic activity and growth of Klebsiella pneumoniae in vitro suggests cobinding of fluoride and acetohydroxamic acid at the urease active site and provides a novel strategy to combat ureolytic bacteria.

The ability of ureolytic bacteria to break down stable urea to alkaline ammonia leads to several environmental and health challenges. Ureolytic bacteria such as Helicobacter pylori, Klebsiella pneumoniae, and Proteus mirabilis can become pathogenic and cause persistent infections that can be difficult to treat. Inhibiting urease activity can reduce the growth and pathogenicity of ureolytic bacteria. In the present in vitro study, we investigated the synergistic effects of tannic acid (TA) and the urease inhibitors fluoride (F-) and acetohydroxamic acid (AHA). The concentration of AHA needed for efficient inhibition of the ureolytic activity of K. pneumoniae can be significantly reduced if AHA is coapplied with tannic acid and sodium fluoride (NaF). Thus, only 1.20 µmol l-1 AHA in combination with 0.30 mmol l-1 tannic acid and 0.60 mmol l-1 NaF delayed the onset of ureolytic pH increase by 95.8 % and increased the growth lag phase by 124.3 % relative to untreated K. pneumoniae. At these concentrations, without AHA, TA and NaF increased the onset of the ureolytic pH change by only 37.0 % and the growth lag phase by 52.5 %. The strong inhibition obtained with low concentrations of AHA in triple-compound treatments suggests cobinding of F- and AHA at the urease active site and could reduce the side effects of AHA when it is employed as a drug against e.g. urinary tract infections (UTIs) and blocked catheters. This study reports the basis for a promising novel therapeutic strategy to combat infections caused by ureolytic bacteria and the formation of urinary tract stones and crystalline biofilms on catheters.

Caries preventive potential of professionally deliverable fluoride-containing agents with incorporated arginine: A scoping review.

The scoping review objectives were to: 1) investigate the caries preventive potential of professionally deliverable fluoride (F)-containing agents with incorporated arginine (Arg); and 2) identify the future scope of research on Arg-F interventions for caries prevention. Of 150 identified records, 7 articles (6 in vitro investigations and 1 scoping review) were included for a complete review; with no clinical studies with/without appraisal. Arginine variants (L-Arg/Arg.HCl at 1% to 10% w/v.) were examined for a potential professional application aimed at caries prevention, as reported with in vitro studies. Of the included articles, four in vitro studies explored L-Arg enriched 5% NaF varnish (Duraphat®) as a promising caries preventive agent, while only one considered incorporating L-Arg in MI varnish®/nanohydroxyapatite and one investigated glass ionomer cement for primary/secondary and tertiary caries prevention. The scoping review highlighted the scope for incorporating Arg to professionally deliverable F-containing agents. No clinical data are available to make conclusive recommendations about the caries preventive potential of professionally deliverable F-containing agents with incorporated Arg. With Arg-F varnish being investigated predominantly through in vitro studies, the data so far suggest that Arg was incorporated exclusively in Duraphat®, while the potential of Arg to prevent caries in other F-containing varnishes remains unexplored.

Skeletal fluorosis: an uncommon cause, yet a rescue treatment?

PURPOSE: Skeletal fluorosis (SF) results from chronic exposure to fluoride (F-) causing excessive aberrantly mineralized brittle bone tissue, fractures, and exostoses. There is no established treatment other than avoiding the source of F-. Still, excess F- can persist in bone for decades after exposure ceases. CASE PRESENTATION: A 50-year-old woman presented with multiple, recurrent, low AQ2 trauma fractures yet high radiologic bone mineral density. Serum F- was elevated, and osteomalacia was documented by non-decalcified transiliac biopsy. She reported intermittently "huffing" a keyboard cleaner containing F- (difluoroethane) for years. Following cessation of her F- exposure, we evaluated the administration of the parathyroid hormone analog, abaloparatide, hoping to increase bone remodeling and diminish her skeletal F- burden. CONCLUSION: Due to the prolonged half-life of F- in bone, SF can cause fracturing long after F- exposure stops. Anabolic therapy approved for osteoporosis, such as abaloparatide, may induce mineralized bone turnover to replace the poorly mineralized osteomalacic bone characteristic of SF and thereby diminish fracture risk. Following abaloparatide treatment for our patient, there was a decrease in bone density as well as a reduction in F- levels.

Defluorination of monofluorinated alkane by Rhodococcus sp. NJF-7 isolated from soil.

Microbial degradation of fluorinated compounds raised significant attention because of their widespread distribution and potential environmental impacts. Here, we report a bacterial isolate, Rhodococcus sp. NJF-7 capable of defluorinating monofluorinated medium-chain length alkanes. This isolate consumed 2.29 ± 0.13 mmol L- 1 of 1-fluorodecane (FD) during a 52 h incubation period, resulting in a significant release of inorganic fluoride amounting to 2.16 ± 0.03 mmol L- 1. The defluorination process was strongly affected by the initial FD concentration and pH conditions, with lower pH increasing fluoride toxicity to bacterial cells and inhibiting enzymatic defluorination activity. Stoichiometric conversion of FD to fluoride was observed at neutral pH with resting cells, while defluorination was significantly lower at reduced pH (6.5). The discovery of the metabolites decanoic acid and methyl decanoate suggests that the initial attack by monooxygenases may be responsible for the biological defluorination of FD. The findings here provide new insights into microbial defluorination processes, specifically aiding in understanding the environmental fate of organic semi-fluorinated alkane chemicals.

Adsorption of arsenic and fluoride: Modeling of single and competitive adsorption systems.

The elevated co-occurrence of arsenic and fluoride in surface and groundwater poses risks to human health in many parts of the world. Using single and competitive batch equilibrium adsorption studies, this research focuses on As(V) and F adsorption by activated carbon and its modeling. BET, XRD, FESEM, EDS, and FTIR analysis were used to discern the structural characteristics of activated carbon. The influence of dosage, pH, and contact time were also investigated in single and simultaneous adsorption systems. The maximum adsorption capacity of activated carbon for arsenic and fluoride were found to be 3.58 mg/g and 2.32 mg/g, respectively. Kinetics studies indicated that pseudo-second-order kinetic model fit better than pseudo-first-order, Elovich, and intraparticle diffusion kinetic models. The non-linear regression analysis of Langmuir, Freundlich, Toth, Redlich Petersons, and Modified Langmuir Freundlich models was used to determine single-component asorption model parameters. Additionally, the simultaneous adsorption was rigorously modeled and compared using the Extended Langmuir (EL), Extended Langmuir Freundlich (ELF), Modified Competitive Langmuir (MCL), and Jeppu Amrutha Manipal Multicomponent (JAMM) isotherm models, and competitive mechanisms were interpreted for the simultaneous adsorption system. Further, the model performances were evaluated by statistical error analysis using the normalized average percentage error (NAPE), root mean square errors (RMSE), and the correlation coefficient (R2). According to the modeling results, single equilibrium data fitted better with the Modified Langmuir Freundlich isotherm model, with a higher R2 of 0.99 and lower NAPE values of 3.8 % and 1.28 % for As(V) and F, than other models. For the binary adsorption, the Extended Langmuir Freundlich isotherm model demonstrated excellent fit with lowest errors. All the competitive isotherm models fit the As(V) and F simultaneous sorption systems reasonably well. Furthermore, the research unveiled a nuanced hierarchy of isotherm fitting, with ELF > EL > MCL > JAMM in varying arsenic at a constant fluoride concentration, and ELF > JAMM > EL > MCL in varying fluoride at a constant arsenic concentrations. In addition, competitive studies divulged crucial insights into selective adsorption, as As(V) exhibits a pronounced adsorption selectivity over F on activated carbon. In essence, As(V) showed a more pronounced antagonistic behavior over F, whereas F exhibited a much lesser competitive behavior in the adsorption of arsenic.

Recommendations on Topical Fluoride Usage for Caries Management in East Asia.

Dental caries is a widespread oral health issue in Asia, affecting an estimated 30% to 90% of children and adults. Many caries cases remain untreated, resulting in pain and infection. In response, the Asian Academy of Preventive Dentistry (AAPD) emphasises comprehensive caries management and organised a fluoride workshop at the 15th International Conference of the AAPD in 2023. The AAPD invited a group of experts to form a fluoride working group to review existing literature and develop fluoride recommendations for stakeholders across Asian countries and regions. The working group assessed caries risk and identified commonly used topical fluoride products for home care, professional, and community settings in Asia. The working group concluded that fluoride is a safe and highly effective strategy to reduce caries prevalence and incidence. The working group provided key recommendations based on successful regional caries management practices: (1) use topical fluoride for prevention and control of dental caries; (2) encourage the use of fluoride toothpaste with a concentration of at least 1,000 ppm for effective caries reduction; (3) advise a 0.05% fluoride mouth rinse as soon as children can spit it out to prevent early childhood caries; (4) deliver professionally administered fluoride, such as 5% sodium fluoride varnish, 2% fluoride gel, or 1.23% acidulated phosphate fluoride preparations, to decrease dental caries in at-risk individuals; and (5) apply 38% silver diamine fluoride to arrest cavitated caries. These recommendations aim to help practitioners, health care providers, and parents/caregivers make informed decisions about fluoride use as part of comprehensive oral health care in the region.

Knowledge, Attitudes, and Practices About the Use of Silver Diamine Fluoride Among Dentists in Riyadh, Saudi Arabia: A Cross-Sectional Study.

Introduction Dental caries is a worldwide disease affecting children and older populations. There are multiple interventions to treat dental caries that could be sometimes hard to deliver, due to the general status of patients such as insufficient cooperation or medically compromising conditions. Therefore, another alternative to control dental caries is being used and has been recently introduced and approved by the Saudi FDA which is silver diamine fluoride (SDF).  Objectives This study aimed to investigate the level of knowledge, attitudes, and practices about the use of SDF among dentists in Riyadh, Saudi Arabia. Materials and methods This cross-sectional study was conducted using pretested, an online digitally designed questionnaire sent to 500 Saudi Commission for Health Specialties (SCFHS) registered dentists working in the following specialties: general practitioners, interns, restorative, family, pediatric, and public health dentists who are working in public and private hospitals and clinics. One-way ANOVA was used to determine the comparison of participants' knowledge and Practice with three variables (participants' specialty, place of work, and years of experience), while Chi-square was used for the comparison of respondent's attitudes about the use of SDF and the above same variables. Result A total of 265 responses were received (response rate is 53%). The majority of the respondents were general practitioners and interns 144 (54.3%). Over 50% of dentists believed that they were very informed about SDF. The mean score of knowledge and practices of SDF of participants was found below average 49.13 (19.81) and 43 (26.12), respectively. Correlation of the mean score knowledge and practicing SDF with the type of specialty showed that pediatric dentists had statically significant (P<0.05) higher mean of knowledge 66.94 (SD=17.64) and practicing of SDF 61.93 (22.12) as compared to other specialties, while no statistically significant differences were found among the groups in the overall knowledge and practices based on years of experience and workplace. Attitudes were correlated with the three above variables (specialty, years of experience, and place of work) and showed that pediatric dentists had the highest satisfaction with the results of SDF (85.3%) and were more willing to recommend using it to others (91.2%) as compared to the other groups(P<0.05). No statistically significant differences were found with respect to the later variables. Conclusion The findings of this study showed that irrespective of the positive attitude of participants towards SDF, pediatric dentists were found to have higher knowledge and use SDF more than other dentists in different specialties. Furthermore, they showed higher satisfaction with its use. Years of experience and workplace had no effect on the level of knowledge or practice among participants.

Acceptance of the use of silver fluoride among Brazilian parents of children with special health care needs.

Background: Children with special health care needs including Down Syndrome, Autism Spectrum Disorder and Down Syndrome experience difficulties in receiving dental treatment. Silver Diamine Fluoride (SDF) and Silver Fluoride (SF) are a minimally invasive treatments options to arrest dental caries without sedation; local or general anaesthesia (GA). Aim: Evaluation of Brazilian's parents' acceptance of the use of SF in CSHCN. Methods: After receiving education on SF, 100 Parents of CSHCN completed a questionnaire concerning their acceptance of SF, in different dental situation. Result: Majority of parents (74,5%) agreed to the use of SF for their children. SF was more acceptable on posterior teeth (74,5%) when compared to its use on anterior teeth (43,1%). Parents accepted to use SF in order: to reduce infection and pain (82,4%); to avoid dental injection (72,5%) and treatment under GA (84,3%). The Majority of parents accepted the properties of SF (82,4%) and Silver (80,4%). Conclusion: Silver Fluoride was accepted as a treatment option for caries, by Brazilian parents of CSHCN. SF should be considered as a treatment option for caries limited to dentine for CSHCN, taking into consideration the individual needs and opinions with regard to aesthetics and exposure to fluoride and silver.

Fluoride exposure during puberty induces testicular impairment via ER stress-triggered apoptosis in mice.

Fluoride, a ubiquitous environmental compound, carries significant health risks at excessive levels. This study investigated the reproductive toxicity of fluoride exposure during puberty in mice, focusing on its impact on testicular development, spermatogenesis, and underlying mechanisms. The results showed that fluoride exposure during puberty impaired testicular structure, induced germ cell apoptosis, and reduced sperm counts in mice. Additionally, the SOD activity and GSH content were significantly decreased, while MDA content was significantly elevated in the NaF group. Immunohistochemistry showed an increase in the number of cells positive for GRP78, a key ER stress marker. Moreover, qRT-PCR and Western blot analyses confirmed the upregulation of both Grp78 mRNA and protein expression, as well as increased mRNA expression of other ER stress-associated genes (Grp94, chop, Atf6, Atf4, and Xbp1) and enhanced protein expression of phosphorylated PERK, IRE1α, eIF2α, JNK, XBP-1, ATF-6α, ATF-4, and CHOP. In conclusion, our findings demonstrate that fluoride exposure during puberty impairs testicular structure, induces germ cell apoptosis, and reduces sperm counts in mice. ER stress may participate in testicular cell apoptosis, and contribute to the testicular damage and decreased sperm counts induced by fluoride.

The influence of geology on the quality of groundwater for domestic use: a Kenyan review.

Kenya's population, akin to other Sub-Saharan countries, is rapidly growing. With the increasing unreliability of surface water, groundwater resources are becoming highly relied on for domestic and industrial use. Despite several known contaminants reported in different parts of the country, no study has attempted to correlate groundwater quality in the different geological provinces. This review critically synthesizes the influence of Kenya's diverse geology on groundwater quality for human consumption. This was achieved through a review of published journal articles and other research material through research and government databases. Groundwater was categorised based on the major geological provinces including the Archaean volcanic Nyanzian Craton, the Proterozoic metamorphic Mozambique Mobile Belt (MMB) and volcanic Kisii Group, the Palaeozoic and Mesozoic sediments, and Tertiary volcanic Rift Valley. Groundwater quality in these regions showed a characteristic high concentration of fluoride (F-) in volcanic aquifers of the Rift Valley and Nyazian Craton and metamorphic aquifers of the MMB, where mineral dissolution was the main process of F- release. High salinity was common in metamorphic aquifers in the MMB and the Palaeozoic and Mesozoic sedimentary aquifers where mineral dissolution and seawater intrusion were the common contributors to salinity. Other contaminants such as lead and iron were reported in localised areas in the sedimentary and metamorphic aquifers, respectively. Anthropogenic contaminants such as Escherichia coli (E. coli), NO3 -, and NO2 - were common in shallow groundwater resources in most informal settlements in urban areas. Due to the presence of health implications, of the highlighted contaminants, such as fluorosis, high blood pressure and diarrhoea (due to high F- and salinity) in affected regions, this review highlights the need for an active water resource management program in any country relying on groundwater resources to determine the presence of all region-specific potentially harmful chemical elements and mitigation measures in all its water resources.

Unlocking the Potential: Atomically Thin 2D Fluoritene from Exfoliated Fluorite Ore and Its Electrochemical Activity.

Fluorite mineral holds significant importance because of its optoelectronic properties and wide range of applications. Here, we report the successful exfoliation of bulk fluorite ore (calcium fluoride, CaF2) crystals into atomically thin two-dimensional fluoritene (2D CaF2) using a highly scalable liquid-phase exfoliation method. The microscopic and spectroscopy characterizations show the formation of (111) plane-oriented 2D CaF2 sheets with exfoliation-induced material strain due to bond breaking, leading to the changes in lattice parameter. Its potential role in electrocatalysis is further explored for deeper insight, and a probable mechanism is also discussed. The 2D CaF2 with long-term stability shows overpotential values of 670 and 770 mV vs RHE for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, at 10 mA cm-2. Computational simulations demonstrate the unique "direct-indirect" band gap switching with odd and even numbers of layers. Current work offers new avenues for exploring the structural and electrochemical properties of 2D CaF2 and its potential applicability.

Chemical etching of CAD-CAM glass-ceramic-based materials using fluoride solutions for bonding pretreatment.

The surface treatment of glass-ceramic-based materials, namely, lithium disilicate glass (IPS e.max CAD), feldspar porcelain (VITABLOCS Mark II), and a polymer-infiltrated ceramic network (VITA ENAMIC), using aqueous fluoride solutions and their influence on luting agent bonding were investigated. Six experimental aqueous fluoride solutions were applied to these materials, and their effects were assessed by surface topological analysis. The obtained results were compared using non-parametric statistical analyses. Ammonium hydrogen fluoride (AHF) etchant demonstrated the greatest etching effect. Subsequent experiments focused on evaluating different concentrations of the AHF etchant for the bonding pretreatment of glass-ceramic-based materials with a luting agent (PANAVIA V5). AHF, particularly at concentrations above 5 wt%, effectively roughened the surfaces of the materials and improved the bonding performance. Notably, AHF at a concentration of 30 wt% exhibited a more pronounced effect on both etching and bonding capabilities compared to hydrofluoric acid.

Zirconium­cerium modified polyvinyl alcohol/NaCMC biocomposite film: Synthesis of films through high-speed shear assisted technique and removal fluoride from water.

A new zirconium and cerium-modified polyvinyl alcohol (PVA) sodium carboxymethyl cellulose (NaCMC) film (PVA/CMC-Zr-Ce) was synthesized thru a high-speed shear-assisted method and its adsorption for the removal of fluoride was studied, in which the NaCMC provided -COONa for ion exchange between Na and Zr-Ce, thus the loading amount of Zr-Ce on films was accordingly increased. The morphology and structure of PVA/CMC-Zr-Ce were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Besides, the mechanical properties, water contact angle, and swelling ratio of film were also evaluated. The addition of high-speed shear improved the dispersion of the emulsion system, and PVA/CMC-Zr-Ce film with good adsorption performance and film stability was prepared. While, it was found that the adsorption capacity could reach 67.25 mg/g and equilibrium time could reach 20 min. The adsorption mechanism of PVA/CMC-Zr-Ce revealed that ion exchange between hydroxide and fluoride, electrostatic interactions and complexation were the dominating influencing factors. Based on these findings, it can be concluded that PVA/CMC-Zr-Ce film- synthesized with high-speed shear assistance technique is a promising adsorbent for fluoride removal from water.

The Effect of Non-Invasive Treatment Techniques on the Color Masking Ability and Surface Roughness of Induced Enamel Lesions (An in vitro Study).

Aim of the Study: The aim of this in vitro study was to evaluate the effect of the resin infiltration technique and remineralization of induced enamel caries with fluoride solution on the color masking of white spot lesions and surface roughness. Materials and Methods: A total of 45 sound teeth were used in this study. All the teeth were sectioned along the long axes into two halves, lingual and buccal to get 90 specimens. All specimens were immersed in a demineralized solution for 7 days. The specimens were divided randomly into three equal groups (n = 30) according to the type of treatment; Group 1 (n = 30) was treated with fluoride varnish (Clinpro); Group 2 (n = 30) was treated by resin infiltration (Icon); and Group 3 (n = 30) was used as a control group with no treatment. The color and surface roughness were measured three times at baseline (T1), directly after induction of artificial white spot lesions (WSLs) (T2), and directly after application of the treatment options (T3). The colors were measured using a portable reflective spectrophotometer and the 3D surface roughness was measured using a Light Sectioning Vision System. Data were collected and statistically analyzed using T test and Mann-Whitney U test. The Results: Surface roughness was almost equal in the study groups with no statistically significant differences reported. Icon showed slightly higher color scores than that of ClinPro. Conclusions: The Icon produced favorable esthetic results compared to the fluoride therapy while no significant differences were reported regarding the surface roughness.

Assessment of Remineralization Ability of Different Fluoride Varnishes on Artificial Enamel Lesion of Primary Teeth - A Comparative Study.

Aim: The current study's aim was to evaluate the potential of various fluoride varnishes to remineralize artificial enamel lesions on primary teeth. Materials and Methods: For the study, 90 deciduous molar teeth that were implicated for extraction were taken. A window region with a size of 3 × 3 mm was located in the middle of the tooth's coronal surface. The remaining portion was given a coat of nail polish and given time to dry. A demineralizing solution was used to create the artificial enamel lesion. The samples were randomized into three experimental groups at random, with 30 samples in each group. Group 1: Application of Clinpro White Varnish, Group 2: Application of Duraphat Varnish, and Group 3: Application of MI Varnish. After 14 days, samples from each group were examined under scanning electron microscopy at a magnification of 1000× to determine whether remineralization had occurred. Microhardness was also determined using a microhardness tester. Result: Before the intervention, the mean demineralized enamel lesion in the Clinpro White Varnish group was 134.44 ± 0.04, in the Duraphat Varnish group was 133.76 ± 0.12, and in the MI Varnish group was 133.89 ± 0.08. After intervention, the maximum remineralized area was found in the MI Varnish group (82.74 ± 0.18) followed by the Clinpro White Varnish group (101.43 ± 0.16) and the Duraphat Varnish group (104.11 ± 0.10). After the intervention, there was a statistically significant difference found between the groups. After the intervention, the maximum microhardness mean value improved in the MI Varnish group (257.03 ± 1.09 to 261.18 ± 1.20) followed by Clinpro White Varnish (258.78 ± 1.64 to 260.10 ± 1.22) and Duraphat Varnish group (255.24 ± 1.51 to 258.02 ± 0.89). Conclusion: According to the findings of the current investigation, all of the varnishes utilized in this in vitro experiment are capable of correcting early enamel defects on primary teeth. However, MI Varnish group was very effective compared to the Clinpro White Varnish group and the Duraphat Varnish group.

Carboxymethyl chitosan composited poly(ethylene oxide) electrolyte with high ion conductivity and interfacial stability for lithium metal batteries.

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.