Acid-Triggered Degradation of Three-In-One Ag2S Quantum Dots for In Situ Ratiometric NIR-II Fluorescence Imaging-Guided Ion/Gas Combination Therapy.

Smart theranostic nanoprobes with the integration of multiple therapeutic modalities are preferred for precise diagnosis and efficient therapy of tumors. However, it remains a big challenge to arrange the imaging and two or more kinds of therapeutic agents without weakening the intended performances. In addition, most existing fluorescence (FL) imaging agents suffer from low spatiotemporal resolution due to the short emission wavelength (<900 nm). Here, novel three-in-one Ag2S quantum dot (QD)-based smart theranostic nanoprobes were proposed for in situ ratiometric NIR-II FL imaging-guided ion/gas combination therapy of tumors. Under the acidic tumor microenvironment, three-in-one Ag2S QDs underwent destructive degradation, generating toxic Ag+ and H2S. Meanwhile, their FL emission at 1270 nm was weakened. Upon introduction of a downconversion nanoparticle (DCNP) as the delivery carrier and NIR-II FL reference signal unit, the formed Ag2S QD-based theranostic nanoprobes could achieve precise diagnosis of tumors through ratiometric NIR-II FL signals. Also, the generated Ag+ and H2S enabled specific ion/gas combination therapy toward tumors. By combining the imaging and therapeutic functions, three-in-one Ag2S QDs may open a simple yet reliable avenue to design theranostic nanoprobes.

Biogenic synthesis, characterization, and in vitro biological investigation of silver oxide nanoparticles (AgONPs) using Rhynchosia capitata.

The current research aimed to study the green synthesis of silver oxide nanoparticles (AgONPs) using Rhynchosia capitata (RC) aqueous extract as a potent reducing and stabilizing agent. The obtained RC-AgONPs were characterized using UV, FT-IR, XRD, DLS, SEM, and EDX to investigate the morphology, size, and elemental composition. The size of the RC-AgONPs was found to be ~ 21.66 nm and an almost uniform distribution was executed by XRD analysis. In vitro studies were performed to reveal biological potential. The AgONPs exhibited efficient DPPH free radical scavenging potential (71.3%), reducing power (63.8 ± 1.77%), and total antioxidant capacity (88.5 ± 4.8%) to estimate their antioxidative power. Antibacterial and antifungal potentials were evaluated using the disc diffusion method against various bacterial and fungal strains, and the zones of inhibition (ZOI) were determined. A brine shrimp cytotoxicity assay was conducted to measure the cytotoxicity potential (LC50: 2.26 µg/mL). In addition, biocompatibility tests were performed to evaluate the biocompatible nature of RC-AgONPs using red blood cells, HEK, and VERO cell lines (< 200 µg/mL). An alpha-amylase inhibition assay was carried out with 67.6% inhibition. Moreover, In vitro, anticancer activity was performed against Hep-2 liver cancer cell lines, and an LC50 value of 45.94 µg/mL was achieved. Overall, the present study has demonstrated that the utilization of R. capitata extract for the biosynthesis of AgONPs offers a cost-effective, eco-friendly, and forthright alternative to traditional approaches for silver nanoparticle synthesis. The RC-AgONPs obtained exhibited significant bioactive properties, positioning them as promising candidates for diverse applications in the spheres of medicine and beyond.

Novel Ag3PO4/ZnWO4-modified graphite felt electrode for photoelectrocatalytic removal of harmful algae: Performance and mechanism.

A novel Ag3PO4/ZnWO4-modified graphite felt electrode (AZW@GF) was prepared by drop coating method and applied to photoelectrocatalytic removal of harmful algae. Results showed that approximately 99.21% of chlorophyll a and 91.57% of Microcystin-LR (MCLR) were degraded by the AZW@GF-Pt photoelectrocatalytic system under the optimal operating conditions with a rate constant of 0.02617 min-1 and 0.01416 min-1, respectively. The calculated synergistic coefficient of photoelectrocatalytic algal removal and MC-LR degradation by the AZW@GF-Pt system was both larger than 1.9. In addition, the experiments of quenching experiments and electron spin resonance (ESR) revealed that the photoelectrocatalytic reaction mainly generated •OH and •O2- for algal removal and MC-LR degradation. Furthermore, the potential pathway for photoelectrocatalytic degradation of MC-LR was proposed. Finally, the photoelectrocatalytic cycle algae removal experiments were carried out on AZW@GF electrode, which was found to maintain the algae removal efficiency at about 91% after three cycles of use, indicating that the photoelectrocatalysis of AZW@GF electrode is an effective emergency algae removal technology.

Understanding the different effects of fouling mechanisms on working and reference electrodes in fast-scan cyclic voltammetry for neurotransmitter detection.

Fast-scan cyclic voltammetry (FSCV) is a widely used technique for detecting neurotransmitters. However, electrode fouling can negatively impact its accuracy and sensitivity. Fouling refers to the accumulation of unwanted materials on the electrode surface, which can alter its electrochemical properties and reduce its sensitivity and selectivity. Fouling mechanisms can be broad and may include biofouling, the accumulation of biomolecules on the electrode surface, and chemical fouling, the deposition of unwanted chemical species. Despite individual studies discussing fouling effects on either the working electrode or the reference electrode, no comprehensive study has been conducted to compare the overall fouling effects on both electrodes in the context of FSCV. Here, we examined the effects of biofouling and chemical fouling on the carbon fiber micro-electrode (CFME) as the working electrode and the Ag/AgCl reference electrode with FSCV. Both fouling mechanisms significantly decreased the sensitivity and caused peak voltage shifts in the FSCV signal with the CFME, but not with the Ag/AgCl reference electrode. Interestingly, previous studies have reported peak voltage shifts in FSCV signals due to the fouling of Ag/AgCl electrodes after implantation in the brain. We noticed in a previous study that energy-dispersive spectroscopy (EDS) spectra showed increased sulfide ion concentration after implantation. We hypothesized that sulfide ions may be responsible for the peak voltage shift. To test this hypothesis, we added sulfide ions to the buffer solution, which decreased the open circuit potential of the Ag/AgCl electrode and caused a peak voltage shift in the FSCV voltammograms. Also, EDS analysis showed that sulfide ion concentration increased on the surface of the Ag/AgCl electrodes after 3 weeks of chronic implantation, necessitating consideration of sulfide ions as the fouling agent for the reference electrodes. Overall, our study provides important insights into the mechanisms of electrode fouling and its impact on FSCV measurements. These findings could inform the design of FSCV experiments, with the development of new strategies for improving the accuracy and reliability of FSCV measurements in vivo.

Postoperative instructions for silver diamine fluoride therapy: A scoping review of current evidence and practice.

OBJECTIVES: Silver diamine fluoride (SDF) has gained popularity in dentistry as an anti-hypersensitive and anti-caries agent. This study aims to review the postoperative instructions for SDF therapy and examine the evidence supporting these instructions in treating dentine hypersensitivity and caries control. DATA AND SOURCES: Two independent reviewers searched three electronic databases (EMBASE, PubMed, and Web of Science) to identify clinical studies that used SDF to treat dentine hypersensitivity and dental caries. Additionally, they searched Google Chrome for information from manufacturers, the department of health, national dental organisations, authoritative dental organisations, and universities regarding SDF therapy for these conditions. Data on postoperative instructions were extracted, and their impact on the treatment of dentine hypersensitivity and caries control was investigated. STUDY SELECTION: This review included 74 clinical studies, 11 sets of instructions from SDF manufacturers, and six recommendations from national dental organisations, departments of health and universities. Amongst the included records, 50 clinical studies, two manufacturers, and one department of health mentioned postoperative instructions for SDF therapy. The recommendations varied, from suggesting no specific instructions, immediate rinsing, refraining from eating or drinking for 30 to 60 min, and even avoiding brushing until the next day after SDF therapy. Notably, no clinical studies reported the effects of these postoperative instructions on the SDF treatment of dentine hypersensitivity or dental caries. CONCLUSIONS: This scoping review highlights the presence of inconsistent postoperative instructions for SDF therapy in the treatment of dentine hypersensitivity and caries control. Furthermore, there is a lack of evidence supporting the effectiveness of these instructions. CLINICAL SIGNIFICANCE: No evidence supports the postoperative instructions for SDF therapy for managing dentine hypersensitivity and dental caries. Studies are necessary to provide guidance for clinicians using SDF in their clinical practice.

Silver vanadate nanomaterial incorporated into heat-cured resin and coating in printed resin - Antimicrobial activity in two multi-species biofilms and wettability.

OBJECTIVES: To incorporate the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) into denture base materials: heat-cured (HC) and 3D printed (3DP) resins, at concentrations of 2.5 %, 5 %, and 10 %; and to evaluate the antimicrobial activity in two multi-species biofilm: (1) Candida albicans, Candida glabrata, and Streptococcus mutans, (2) Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus, and the wettability. METHODS: The AgVO3 was added to the HC powder, and printed samples were coated with 3DP with AgVO3 incorporated. After biofilm formation, the antimicrobial activity was evaluated by colony forming units per milliliter (CFU/mL), metabolic activity, and epifluorescence microscopy. Wettability was assessed by the contact angles with water and artificial saliva. RESULTS: In biofilm (1), HC-5 % and HC-10 % showed activity against S. mutans, HC-10 % against C. glabrata, and HC-10 % and 3DP-10 % had higher CFU/mL of C. albicans. 3DP-5 % had lower metabolic activity than the 3DP control. In biofilm (2), HC-10 % reduced S. aureus and P. aeruginosa, and HC-5 %, 3DP-2.5 %, and 3DP-5 % reduced S. aureus. 3DP incorporated with AgVO3, HC-5 %, and HC-10 % reduced biofilm (2) metabolic activity. 3DP-5 % and 3DP-10 % increased wettability with water and saliva. CONCLUSION: HC-10 % was effective against C. glabrata, S. mutans, P. aeruginosa, and S. aureus, and HC-5 % reduced S. mutans and S. aureus. For 3DP, 2.5 % and 5 % reduced S. aureus. The incorporation of AgVO3 into both resins reduced the metabolic activity of biofilms but had no effect on C. albicans. The wettability of the 3DP with water and saliva increased with the addition of AgVO3. CLINICAL SIGNIFICANCE: The incorporation of silver vanadate into the denture base materials provides antimicrobial efficacy and can prevent the aggravation of oral and systemic diseases. The incorporation of nanomaterials into printed resins is challenging and the coating is an alternative to obtain the inner denture base with antimicrobial effect.

Preventive dental erosion with silver diamine fluoride: An in vitro study.

OBJECTIVES: To evaluate the erosion preventive effect of 38 % silver diamine fluoride (SDF) solution in enamel and dentin of human permanent teeth. METHODS: Ninety enamel and ninety dentin blocks were prepared from permanent molars and allocated into three groups. Gp-SDF received a one-off application of 38 % SDF solution. Gp-SNF received a one-off application of a solution containing 800 ppm stannous chloride and 500 ppm fluoride. Gp-DW received a one-off application of deionized water. The blocks were submitted to acid challenge at pH 3.2, 2 min, 5 times/day for 7 days. All blocks were immersed in human saliva between cycles for one hour. The crystal characteristics, percentage of surface microhardness loss (%SMHL), surface loss, and elemental analysis and surface morphology were examined by X-ray diffraction (XRD), microhardness test, non-contact profilometry, and energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM), respectively. Data of%SMHL and surface loss were analyzed by one-way ANOVA. RESULTS: XRD spectra revealed that fluorapatite and silver compounds formed in Gp-SDF, while fluorapatite and stannous compounds formed in Gp-SNF. Gp-DW presented only hydroxyapatite. The median (interquartile range) of%SMHL in Gp-SDF, Gp-SNF and Gp-DW were 27.86(3.66), 43.41(2.45), and 46.40(3.54) in enamel (p< 0.001), and 14.21(1.57), 27.99(1.95), and 33.18(1.73) in dentin, respectively (p < 0.001). The mean (standard deviation, µm) of surface loss of Gp-SDF, Gp-SNF, and Gp-DW were 2.81(0.59), 4.28(0.67), and 4.63(0.64) in enamel (p < 0.001) and 4.13(0.69), 6.04(0.61), and 7.72(0.66) in dentin, respectively (p < 0.001). SEM images exhibited less enamel corruption and more dentinal tubular occlusion in Gp-SDF compared to Gp-SNF and Gp-DW. EDS analysis showed silver was detected in Gp-SDF while stannous was detected in the dentin block of Gp-SNF. CONCLUSION: 38 % SDF yielded superior results in protecting enamel and dentin blocks from dental erosion compared to SNF and DW. CLINICAL SIGNIFICANCE: Topical application of 38 % SDF is effective in preventing dental erosion in human enamel and dentin.

Polyvalent Aptamer-Functionalized NIR-II Quantum Dots for Targeted Theranostics in High PD-L1-Expressing Tumors.

Ag2S quantum dots (QDs) show superior optical properties in the NIR-II region and display significant clinical potential with favorable biocompatibility. However, inherent defects of low targeting and poor solubility necessitate practical modification methods to achieve the theranostics of Ag2S QDs. Herein, we used rolling circle amplification (RCA) techniques to obtain long single-stranded DNA containing the PD-L1 aptamer and C-rich DNA palindromic sequence. The C-rich DNA palindromic sequences can specifically chelate Ag2+ and thus serve as a template to result in biomimetic mineralization and formation of pApt-Ag2S QDs. These QDs enable specific targeting and illuminate hot tumors with high PD-L1 expression effectively, serving as excellent molecular targeted probes. In addition, due to the high NIR-II absorption of Ag2S QDs, pApt-Ag2S QDs exhibit remarkable photothermal properties. And besides, polyvalent PD-L1 aptamers can recognize PD-L1 protein and effectively block the inhibitory signal of PD-L1 on T cells, enabling efficient theranostics through the synergistic effect of photothermal therapy and immune checkpoint blocking therapy. Summary, we enhance the biological stability and antibleaching ability of Ag2S QDs using long single-stranded DNA as a template, thereby establishing a theranostic platform that specifically targets PD-L1 high-expressing inflamed tumors and demonstrates excellent performance both in vitro and in vivo.

Clinical effectiveness/child-patient and parent satisfaction of two topical fluoride treatments for caries: a randomised clinical trial.

Knowledge gaps exist regarding optimal silver diammine fluoride (SDF) regimens and the efficacy of new products for arresting dental caries in young children. We evaluated the effectiveness of 38%-SDF (SDI-RivaStar), Tiefenfluorid (TF) comparing with Placebo (P), all in conjunction with behavioural modification (BM), in preventing major complications (endodontic/extractions/pain)-a patient-centred outcome-due to early childhood caries over 12 months in children under 71-months. A six-arm, patient/parent-blinded, superiority, placebo-controlled randomised control trial at the university clinic in Riga, Latvia, from 1/9/20-31/8/22 (Protocol registration ISRCTN17005348). The trial tested six protocols, using three compounds (P/SDF/TF) under two regimes: annual and biannual (P1/P2/TF1/TF2/SDF1/SDF2) for major complications. Secondary outcomes included minor complications and parental satisfaction. All groups received BM. 373/427 randomised children (87.3%) completed the study. SDF2 had a significantly lower rate and risk of major (21.5%, OR = 0.28, 95%CI [0.11, 0.72], p < 0.05) and minor complications (OR = 0.16 (95%CI [0.05, 0.50], p = 0.002). Overall satisfaction was 96% (p > 0.05). SDF biannual application with BM effectively prevented major complications of early childhood caries and was well accepted by children and their parents. Trial registration number: ISRCTN17005348, principal investigator: Ilze Maldupa, registration date: 30/06/2021.Clinical trial registration number: ISRCTN registry: ISRCTN17005348, https://doi.org/10.1186/ISRCTN17005348 , registration date: 30/06/2021.

Silver Diammine Fluoride Usage in General Dentistry Offices in Louisiana.

Purpose: To evaluate the current knowledge and usage of silver diammine fluoride (SDF) by general dentists in Louisiana and to identify primary barriers to the imple- mentation of SDF. Methods: A 16-item survey was emailed to 1719 Louisiana Dental Association members to identify factors influencing general dentists' usage of SDF. Results: Eighty-two surveys were completed with a response rate of 4.8 percent, with 69 identified as general dentists. Over half of the respondents were male (53.6%) and their practice experience ranged from less than one year to 48 years. The majority were solo owners (43.5%) while 7.3 percent had jobs in the corporate setting. Most agreed/strongly agreed that their knowledge of SDF was from either dental journals or online resources, while fewer stated they were taught about SDF (25%) or used SDF (8%) in dental school. The majority knew the advantages and off-label usage of SDF. However, only 40 percent recognized that SDF was officially approved for tooth hypersensitivity only. The most reported perceived barrier to SDF implementation was not learning about SDF in dental school (36%). Conclusion: There is a lack of understanding of SDF usage among Louisiana general dentists. The main reason for not incorporating SDF into their practice is the lack of training in their dental education.

Comparison of the effects of fluoride varnish containing silver nanoparticles and conventional fluoride varnish on the surface microhardness of tooth enamel.

BACKGROUND: Nano-silver fluoride (NSF) has been introduced to improve enamel lesions. The effective use of varnishes is important in the prevention of dental caries. OBJECTIVES: The study aimed to compare the effect of conventional sodium fluoride varnish with the same varnish containing 1% and 2% silver nanoparticles (AgNP) on the surface microhardness of enamel. MATERIAL AND METHODS: The baseline surface microhardness of 40 premolar teeth was measured using a Vickers microhardness tester. After immersing the samples in a demineralizing agent for 24 h, the microhardness was measured again. In group B, a layer of conventional fluoride varnish was applied to the tooth surfaces using a microbrush with soft bristles, following the manufacturer's instructions. Groups C and D were treated with 1% and 2% NSF varnishes, respectively, while group A received no varnish. Surface microhardness tests were conducted on all specimens, including those previously tested. RESULTS: The microhardness of the enamel surface increased significantly in all 3 test groups compared to the microhardness after demineralization (p < 0.05). CONCLUSIONS: Conventional fluoride varnish and fluoride varnishes containing 1% and 2% AgNP are equally effective in remineralizing initial caries.

Potential-selective electrochemiluminescence of AgInS2/ZnS nanocrystals and its immunoassay application.

Potential-selective electrochemiluminescence (ECL) with tunable maximum-emission-potential ranging from 0.95 to 0.30 V is achieved using AgInS2/ZnS nanocrystals, which is promising in the design of multiplexed bioassay on commercialized ECL setups. The model system AgInS2/ZnS/N2H4 exhibits efficient ECL around 0.30 V and can be exploited for sensitive immunoassays with less electrochemical interference and crosstalk.

Laser fluorescence assessment of dental caries arrest with two silver fluoride agents in patients with special needs- a preliminary report.

PURPOSE: While silver diamine fluoride has been used extensively for caries arrest and desensitising, silver fluoride (AgF) at neutral pH may also have value as a minimally invasive dental caries treatment. This study explored the effectiveness of two AgF products (AgF/KI and AgF/SnF2) when used in adult patients with special needs (SN) who had high caries risk and salivary gland hypofunction. METHODS: This split-mouth clinical study, over two appointments 3-months apart, compared the impact of a single application of AgF/KI (Riva Star Aqua, SDI) and AgF/SnF2 (Creighton Dental CSDS, Whiteley) on matched carious lesions in the same arch, by clinical visual-tactile (cVT) assessment of caries status and laser fluorescence (LF, DIAGNOdent) evaluation of bacterial load in the lesions, using repeated measures analysis. RESULTS: Twelve participants were recruited in the study. A total of 56 teeth (28 pairs) were included. Both AgF products gave a significant decrease in caries activity as measured by cVT (P < 0.0001) and LF (P = 0.0027). There were no statistically significant differences between the two AgF treatments, with response rates for improvements in active lesions of 92% in the AgF/KI arm, and 96% in the AgF/SnF2 arm. There was no effect of tooth type, lesion type, arch type, plaque metabolism and plaque area at the site level on outcomes, nor was there a clustering effect of sites in a patient level analysis. Overall, LF was superior to cVT for detecting lesions that still progressed despite treatment (P = 0.0027). CONCLUSION: A single application of AgF/KI or AgF/SnF2 has high predictability (over 90%) for achieving arrest in active caries lesions in adult patients with SN and high caries risk. Clinical assessment should use visual-tactile examination combined with LF readings to detect lesions that are still progressing and that require additional treatments. Future studies should compare these AgF modalities with SDF and explore factors such as time between applications and the need for repeated applications. TRIAL REGISTRATION: The study was registered with the Australian Clinical Trials Registry (ACTRN12621001139864p) on 23/08/2021.

Unexpected sequel to the application of silver fluoride followed by stannous fluoride to an open carious lesion in a primary molar: A case report.

OBJECTIVES: The use of silver fluoride followed by stannous fluoride was designed for the treatment of open carious lesions in primary molars in dental outreach programs. However, during the COVID-19 pandemic when aerosol-producing procedures were inadvisable, one dental location started using it as the first stage in a two-visit restorative procedure for carious primary molars. If the gap between the fluoride application and the restoration placement stages was around 3-5 weeks it was noticed that a black friable crust appeared on the caries surface. To investigate further a normally discarded crust from one patient was retrieved and sent for analysis. MATERIALS AND METHODS: Two techniques suitable for identification and preliminary analysis of material of unknown composition, scanning electron microscopy and energy dispersive spectroscopy (EDS) were used. The only preparation was that the specimen was dried and coated beforehand. RESULTS AND CONCLUSIONS: This preliminary examination showed two unexpected findings. The first was that the crust surface indicated a possible dentine derivation as it was covered with reasonably evenly spaced holes. In addition, the EDS spectrum showed it to be, at least, partially mineralized. The second unexpected finding was that the surface was coated with electron-dense particles. The size of the particles and the EDS spectrum pointed to the likelihood of the majority of them being nanosilver. These unexpected findings suggest a possible new direction for research.

Noninferiority of Silver Diamine Fluoride vs Sealants for Reducing Dental Caries Prevalence and Incidence: A Randomized Clinical Trial.

Importance: Dental caries is the world's most prevalent noncommunicable disease and a source of health inequity; school dental sealant programs are a common preventive measure. Silver diamine fluoride (SDF) may provide an alternative therapy to prevent and control caries if shown to be noninferior to sealant treatment. Objective: To determine whether school-based application of SDF is noninferior to dental sealants and atraumatic restorative treatment (ART) in the prevalence of dental caries. Design, Setting, and Participants: The Silver Diamine Fluoride Versus Therapeutic Sealants for the Arrest and Prevention of Dental Caries in Low-Income Minority Children (CariedAway) study was a pragmatic noninferiority cluster-randomized clinical trial conducted from February 2018 to June 2023 to compare silver diamine fluoride vs therapeutic sealants for the arrest and prevention of dental caries. Children at primary schools in New York, New York, with at least 50% of the student population reporting as Black or Hispanic and at least 80% receiving free or reduced lunch were included. This population was selected as they are at the highest risk of caries in New York. Students were randomized to receive either SDF or sealant with ART; those aged 5 to 13 years were included in the analysis. Treatment was provided at every visit based on need, and the number of visits varied by child. Schools with preexisting oral health programs were excluded, as were children who did not speak English. Of 17 741 students assessed for eligibility, 7418 were randomized, and 4100 completed follow-up and were included in the final analysis. Interventions: Participants were randomized at the school level to receive either a 38% concentration SDF solution or glass ionomer sealants and ART. Each participant also received fluoride varnish. Main Outcomes and Measures: Primary study outcomes were the prevalence and incidence of dental caries. Results: A total of 7418 children (mean [SD] age, 7.58 [1.90] years; 4006 [54.0%] female; 125 [1.7%] Asian, 1246 [16.8%] Black, 3648 [49.2%] Hispanic, 153 [2.1%] White, 114 [1.5%] multiple races or ethnicities, 90 [1.2%] other [unspecified], 2042 [27.5%] unreported) were enrolled and randomized to receive either SDF (n = 3739) or sealants with ART (n = 3679). After initial treatment, 4100 participants (55.0%) completed at least 1 follow-up observation. The overall baseline prevalence of dental caries was approximately 27.2% (95% CI, 25.7-28.6). The odds of decay prevalence decreased longitudinally (odds ratio [OR], 0.79; 95% CI, 0.75-0.83) and SDF was noninferior compared to sealants and ART (OR, 0.94; 95% CI, 0.80-1.11). The crude incidence of dental caries in children treated with SDF was 10.2 per 1000 tooth-years vs 9.8 per 1000 tooth-years in children treated with sealants and ART (rate ratio, 1.05; 95% CI, 0.97-1.12). Conclusions and Relevance: In this school-based pragmatic randomized clinical trial, application of SDF resulted in nearly identical caries incidence compared to dental sealants and ART and was noninferior in the longitudinal prevalence of caries. These findings suggest that SDF may provide an effective alternative for use in school caries prevention. Trial Registration: ClinicalTrials.gov Identifier: NCT03442309.

The impact of skin preparation method on electrocardiogram quality in horses.

Objective: Several skin preparation techniques are used in electrocardiogram (ECG) monitoring of horses. The objective of this study was to determine which methods produce the greatest signal quality using textile electrodes and standard silver/silver chloride (Ag/AgCl) electrodes. Animals and samples: Electrocardiogram data were collected using textile and Ag/AgCl electrodes simultaneously for 4 skin preparation techniques in 6 horses. Procedure: The effects of skin preparation (cleansing with isopropyl alcohol, with or without shaving the hair) and the effects of the application of a conductive gel were assessed using metrics of signal quality. Results: Shaving and cleansing with alcohol had no effect on signal quality for either electrode type. The Ag/AgCl electrodes contain a solid gel, and the application of additional gel did not affect signal quality. Data quality was significantly improved when gel was applied to textile electrodes. Furthermore, there was no difference in signal quality between electrode types when gel was used. Conclusion and clinical relevance: This study suggests that skin preparation by cleansing and/or shaving does not have a significant effect on equine ECG signal quality. When gel is used, textile electrodes are a practical alternative for Ag/AgCl electrodes, as they produce ECG recordings of the same quality.

Impact de la méthode de préparation de la peau sur la qualité de l'électrocardiogramme chez le cheval. Objectif: Plusieurs techniques de préparation de la peau sont utilisées lors de la surveillance électrocardiographique (ECG) des chevaux. L'objectif de cette étude était de déterminer quelles méthodes produisent la meilleure qualité de signal en utilisant des électrodes textiles et des électrodes standard argent/chlorure d'argent (Ag/AgCl). Animaux et échantillons: Les données d'électrocardiogramme ont été obtenues simultanément à l'aide d'électrodes textiles et d'électrodes Ag/AgCl pour 4 techniques de préparation cutanée chez 6 chevaux. Procédure: Les effets de la préparation de la peau (nettoyage à l'alcool isopropylique, avec ou sans rasage des cheveux) et les effets de l'application d'un gel conducteur ont été évalués à l'aide de métriques de qualité du signal. Résultats: Le rasage et le nettoyage à l'alcool n'ont eu aucun effet sur la qualité du signal pour les deux types d'électrodes. Les électrodes Ag/AgCl contiennent un gel solide et l'application de gel supplémentaire n'a pas affecté la qualité du signal. La qualité des données a été considérablement améliorée lorsque le gel a été appliqué sur des électrodes textiles. De plus, il n'y avait aucune différence dans la qualité du signal entre les types d'électrodes lorsque du gel était utilisé. Conclusion et pertinence clinique: Cette étude suggère que la préparation de la peau par nettoyage et/ou rasage n'a pas d'effet significatif sur la qualité du signal ECG équin. Lorsque du gel est utilisé, les électrodes textiles constituent une alternative pratique aux électrodes Ag/AgCl, car elles produisent des enregistrements ECG de même qualité.(Traduit par Dr Serge Messier).

Potassium Iodide's Effect on Silver Diammine Fluoride Staining Properties as Measured Through Objective Color Analysis Using CIELAB.

Purpose: To determine the effect of potassium iodide (KI) on the black/gray staining caused by silver diammine fluoride (SDF) when applied to carious lesions. Methods: Extracted caries-free molar surfaces had caries induced to examine the use of SDF and SDF followed by KI (SDF+KI) on extracted permanent molars that had caries induced on their surfaces and were monitored for a period after application. To monitor the color changes, CIELAB color space readings???a color space defined by the International Commission on Illumination???were used. The system is composed of three values, of which the L* measures black to white across a span of zero (black) to 100 (white). Measurements were taken at eight intervals between days zero to 72. Results: L* values were found to be significantly different between SDF and SDF+KI groups and from baseline. On average, the SDF+KI group versus the SDF group was 9.47 units lighter. Conclusion: The findings indicate the application of silver diammine fluoride followed by potassium iodide can reduce the black staining SDF alone causes, potentially making it a viable esthetic option for patients with anterior tooth caries.

Silver compounds used in pediatric dentistry for caries arrest: A review of current materials and new technologies.

Silver compounds have been used in medicine and dentistry for centuries. Their use in pediatric dentistry has long been restricted because of some drawbacks, chief among them being the discoloration of teeth with black stains. However, recent advances in technology have resulted in the development of new silver agents that do not have the limitations of previously used ones. This led to the reintroduction of silver compounds in pediatric dentistry. The aim of the present review was to examine the evidence supporting the therapeutic use of silver compounds in pediatric dentistry for caries arrest, as well as the mode of action and biocompatibility, characteristics, advantages, and disadvantages of different silver-containing agents.

A Randomized Clinical Trial to Assess Caries Arrest by Using Silver Diamine Fluoride in U.S. Children: Interim Findings.

Purpose: To assess the effectiveness of 38 percent silver diamine fluoride (SDF) in arresting cavitated caries lesions in young U.S. children. Methods: Children 12 to 71 months of age with severe early childhood caries participated in this phase three, multicenter, randomized, placebocontrolled trial. SDF was applied twice (at baseline and six months), and children were followed for eight months. A planned interim analysis of only the six-month primary outcome caries arrest data, for approximately half of the cohort (680 of 1,144 children), was conducted using a generalized estimating equation model, accounting for non-independence among carious lesions within a patient. Results: Five hundred ninety-nine of the 680 participants, with 1,413 lesions, completed the six-month exam. Lesions in the SDF group demonstrated 54 percent arrest versus 21 percent in the placebo (P<0.001). Conclusions: Silver diamine fluoride was effective at arresting active cavitated lesions in this population, leading to the early stop of the trial. Final analyses of all data and other outcomes are currently underway.

Silver oxide doped iron oxide/alginate nanocomposite coated cotton cloth for selective catalytic reduction of potassium ferricyanide.

Silver oxide doped iron oxide (Ag2O-Fe2O3) nanocatalyst was prepared and coated on cotton cloth (CC) as well as wrapped in sodium alginate (Alg) hydrogel. Ag2O-Fe2O3 coated CC (Ag2O-Fe2O3/CC) and Ag2O-Fe2O3 wrapped Alg (Ag2O-Fe2O3/Alg) were utilized as catalysts in reduction reaction of 4-nitrophenol (4-NP), congo red (CR), methylene blue (MB) and potassium ferricyanide (K3[Fe(CN)6]). Ag2O-Fe2O3/CC and Ag2O-Fe2O3/Alg were found to be effective and selective catalyst for the reaction of K3[Fe(CN)6]. Further amount of catalyst, K3[Fe(CN)6] quantity, amount of NaBH4, stability of catalyst and recyclability were optimized for the reaction of K3[Fe(CN)6] reduction. Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were appeared to be the stable catalysts by maintaining high activity during recyclability tests showing highest reaction rate constants (kapp) of 0.3472 and 0.5629 min-1, correspondingly. However, Ag2O-Fe2O3/CC can be easily recovered as compared to Ag2O-Fe2O3/Alg by simply removing from the reaction which is the main advantage of Ag2O-Fe2O3/CC. Moreover, Ag2O-Fe2O3/Alg and Ag2O-Fe2O3/CC were also examined in real samples and found useful for K3[Fe(CN)6] reduction involving real samples. The Ag2O-Fe2O3/CC nanocatalyst is a cost and time saving material for economical reduction of K3[Fe(CN)6] and environmental safety.