Blue Solution Research Articles

Evaluation of marginal microleakage in Class V restorations with self-adhesive composite resins: an in vitro study

This study aimed to evaluate marginal microleakage in class V restorations using the low-viscosity self-adhesive composite resin Y flow SA and the conventional resin Opallis Flow. Twenty bovine incisors were selected and divided into two groups (n=10): Group OF - Opallis Flow and Group YF - Y flow SA. After cavity preparation, the teeth were restored with the material assigned to each group and then immersed in distilled water for 24 hours. After this period, the specimens were subjected to the microleakage test, which consisted of a 24-hour immersion in a 10% methylene blue solution. The teeth were then sectioned in the buccal-lingual direction and assessed for marginal infiltration. Statistical analysis of the results revealed no significant differences between the groups. The results suggest that, under the tested experimental conditions, the self-adhesive resin may serve as a viable alternative for Class V restorations, offering a substitute for conventional resins that require a separate adhesive system.

A Bayesian Network model to integrate blue-green and gray infrastructure systems for different urban conditions.

In facing growing challenges in cities and the environment, cities need to make informed decisions on where and how to allocate resources for infrastructure investments. Nature-based Solutions present a promising approach to urban environmental and socioeconomic challenges, but their successful integration into urban planning requires a nuanced understanding of both their benefits and limitations. This paper presents a preliminary Bayesian Network model designed to model the optimal integration of specific blue-green and gray Infrastructure solutions in hybrid systems for specific local contexts. The preliminary model considers a wide range of factors related to both infrastructure solutions, giving policymakers suitable arrangements tailored to their specific local conditions. With its probabilistic approach, the Bayesian Network model is a powerful tool for navigating the complex world of infrastructure planning. While the current model provides initial insights, its practical utility will be enhanced through the incorporation of higher-resolution data and application to specific case studies, enabling more accurate, context-sensitive recommendations. This research aims to connect data-driven modeling with practical urban planning, pushing forward the discussion on combining blue, green, and gray solutions for cities that are more sustainable and resilient.

Dynamics of Contaminant Flow Through Porous Media Containing Random Adsorbers

Many porous media are mixtures of inert and reactive materials, manifesting spatio-chemical heterogeneity. We study the evolution of scalar transport in a chemically heterogeneous material that mimics a green roof soil substrate, fractionally composed of inert and reactive adsorbing particles. These adsorbing particles are equivalent to biochar within a real soil substrate. The scalar transport evolution is determined using experiments and simulations calibrated from experimental data. Experiment 1 is used to determine the equilibrium capacity and adsorption rate of two biochar types when immersed in a methylene blue solution. Breakthrough curves of a packed bed of glass beads with randomly interspersed biochar are determined in experiment 2. Simulations are then run to investigate the solute transport and adsorption dynamics at the pore-scale. An analytical model is proposed to capture the behavior of the biochar adsorption capacity, and the simulation results are compared with experiment 2. A pore-scale analysis showed that uniformly sized beds are superior in contaminant breakthrough reduction, which is related to the adsorptive surface area and the rate at which adsorption capacity is reached. Cases using the adsorption capacity model display a tight distribution of particle surface concentration at later simulation times, indicating maximum possible adsorption. The beds with dissimilar particle sizes create more channeling effects which reduce adsorptive particle efficiency and consequently higher breakthrough concentration profiles. Comparison between experiments and simulations show good agreement. Improved biochar performance can be achieved by maintaining particle size uniformity alongside high adsorption capacity and adsorption rates appropriate to the rainfall intensity.

Efficient and sustainable catalytic degradation of methylene blue dye solution by Fe-Si-B amorphous alloy ribbon with large specific surface area

Efficient and sustainable catalytic degradation of methylene blue dye solution by Fe-Si-B amorphous alloy ribbon with large specific surface area

The solid state dispersion method for synthesizing eggshells ES/TiO2 composite to enhance photocatalytic degradation methylene blue.

The use of eggshells as a primary source for developing value-added materials has garnered significant attention in recent years due to their effectiveness as an excellent adsorbent and support. In this study, the Solid-State Dispersion (SSD) method was utilized to prepare composite photocatalysts of eggshells (ES)/TiO₂ in various ratios. TiO₂ and eggshell photocatalysts were also employed as control samples. The samples were characterized using X-ray Diffraction (XRD) to analyze the crystalline structure and phases, along with High-Resolution Transmission Electron Microscopy (HRTEM) to examine the morphology and surface structure at the microscopic level. These characterizations support the data analysis, offering insight into the relationship between structural and morphological properties and the photocatalytic performance of the composites. The photocatalytic efficiency of the composite was assessed in a suspension system using methylene blue (MB) solution as the target pollutant. Among the three different ratios, the ES/TiO2 (9:1) composite achieved the highest adsorption and 95.63 % photocatalytic degradation of MB. This indicates that the adsorptive capacity of eggshells is very high, even though it primarily serves as a support for TiO₂ in the ES/TiO₂ composite photocatalyst. The increased surface area of the TiO₂/eggshell composite photocatalyst enhanced MB solution adsorption and photocatalytic degradation, thereby improving its effectiveness. Overall, it can be concluded that eggshells have excellent potential as a support for photocatalysts and as an environmentally friendly catalyst. Some highlights in this article:•The Solid-State Dispersion (SSD) method is presented as an efficient and eco-friendly approach for synthesizing ES/TiO₂ composites.•ES/TiO₂ composites effectively degraded methylene blue (MB) by 95.63 % under UV light.•This method promotes sustainability by reusing eggshell waste and improving environmental benefits through enhanced photocatalysis.

Bronchoscopic-Guided Selective Endobronchial Injection of Methylene Blue Solution for Localising Peripheral Bronchopleural Fistulas During Pleural Debridement ina Post-Lobectomy Patient With Bronchopleural Fistula and Empyema.

The bronchopleural fistula (BPF) is a pathological passageway between the bronchus and the pleural cavity. Diagnosing andlocalising BPF can be challenging, and the traditional retrograde methylene blue (MB) perfusion method may fail to identify multifocal BPFs. This article reports a novel method for locating multifocal BPFs in patients undergoing concurrentempyemadebridement. Initially, selective endobronchial injection of MB solution is performed under bronchoscopic guidance. Subsequently, the thoracic surgeon determines the location of BPFs as the MB solution flows into the pleural cavity. This process of injecting MB within the bronchus is repeated to locate any additional BPFs until no new ones are found. We report a case where this new method was used to identify multifocal BPFs, ultimately diagnosing three BPFs' presence. Following treatment with bronchopleural fistula occlusion, no recurrence of BPFs was observed during the follow-up period.

Green Synthesis of Silver Nanoparticle Using Usnea cornuta Extract and its Application on Formaldehyde Sensing and Organic Dye Degradation

Silver nanoparticles have been widely used in various electronic and sensing devices, coating materials, molecular switches, and data packing. Green synthesis of silver nanoparticles (Ag NPs) has caught much attention in the present world, as it provides an alternative, eco-friendly, and cost-effective process of synthesizing nanoparticles. In this study, Ag NPs were synthesized using Usnea cornuta which was further applied for colorimetric sensing of methylene blue (MB) and formaldehyde in water. UV-visible, FTIR, and XRD techniques were used to characterize the synthesized Ag NPs. The formation of Ag NPs was confirmed by a color change and UV-visible spectroscopy which showed the absorption peak at 417 nm. The face-centered cubic (FCC) structure of a crystal with an average size of 8.3 nm was determined by XRD. The presence of polyphenolic groups as capping agents was confirmed by FTIR spectra. Moreover, the synthesized Ag NPs were able to detect methylene blue and formaldehyde solution even in diluted solution i.e. 1 ppm and 1 %, for MB and formaldehyde respectively. Additionally, the AgNps can degrade methylene blue solution. The degradation efficiency of AgNps was found to be 80% at four hours. The Usnea cornuta shows good potential as a reducing and stabilizing agent, thus it can be utilized for the biosynthesis of silver nanoparticles. The silver nanoparticle can be utilized to sense organic chemical compounds such as methylene blue and formaldehyde in industrial wastewater as well as other wastes. Thus, Ag NPs show good promising colorimetric sensing abilities.

Evaluation of methylene blue-removal by adsorbents recovered from industrial activity

The study evaluated the application capacity of materials recovered from mining activities (nano hematite recovered from acid mine drainage and basaltic remineralizer (BR) (rock powder) discarded from quarries) as adsorbents in removing methylene blue dye. The adsorbent materials were characterized and had their zero-charge point determined, with pHPCZ 6.5 for rock powder and 5.5 for hematite. The results showed that the basaltic remineralizer contains 51.1% silicon dioxide, 15.2% hematite, and 13.2% alumina. The analysis also indicated that the levels of heavy metals in the rock powder were within the limits established by CONAMA resolution 420/2008, suggesting safety in its application in the environment. The adsorption tests were performed in batches, using 0.5 g of adsorbent in 100 mL of 10 mg. L-1 methylene blue solution. The experiments were performed in triplicate in the pH range of 2 to 6. The dye removal capacity was satisfactory, with hematite removing an average of 1.73 mg. g-1 and basaltic rock powder 2.08 mg. g-1. The greater efficiency of basaltic rock powder, even with a smaller amount of hematite (approximately 0.08 g), can be attributed to the concomitant presence of alumina, offering more active sites for dye adsorption. This study suggests new possibilities for removing textile dyes from effluents and adds commercial value to basaltic rock powder, a byproduct of the mining industry, and nanoparticles recovered from industrial activity.

AN EFFECT OF APICAL PREPARATION ON THE QUALITY OF ENDODONTIC TREATMENT

Relevance: The apical third of the root canal is difficult to access for high-quality endodontic treatment due to the complex anatomical and morphological structure of this area, which includes anastomoses, extra canals, apical deltas, various shapes of the apical foramen. Based on this, the accomplishment of suitable mechanical preparation of the apical part of the root canal remains one of the most complex and important tasks for successful endodontic treatment. Aim: to evaluate the impact of mechanical preparation of the lower third of the root canal on the quality of endodontic treatment. Materials and methods: 30 extracted teeth (incisors, premolars, molars), which root canals had been mechanical and medicamentous processing, were examined. All teeth were divided into two groups based on the extent of apical preparation: up to №25 and №50 according to ISO. The root canal obturation was done with the technique of vertical condensation of gutta-percha. The X-ray diagnostics was used to control the quality of obturation. Teeth from each group that met the inclusion criteria were placed in a solution of methylene blue. Then, transversal cuts were received with a separation disc. The degree of dye penetration into the dentin of the root canal was recorded on these cuts. Results: The study results demonstrated that the adhesion of the filling material to the walls of the root canal was significantly worse in the first group of teeth (apical enlargement up to 25/04), compared to the second group (apical enlargement to 50/04). Conclusion: The root canal enlargement only to №25 according to ISO is not enough for the complete removal of contaminated dentin and the accomplishment of high-quality obturation. The suitable mechanical preparation of the apical part with large sizes allows do more thorough irrigation of the root canal and subsequent obturation, which is a keystone for successful endodontic treatment.

Comparative performance of marking of small-diameter peripheral lung neoplasms by preoperative transthoracic use of methylene blue preparations and placement of an anchor marker system

The study compared marking of small-diameter peripheral lung neoplasms by preoperative transthoracic use of 1% aqueous methylene blue solution and placement of an anchor marker system. The study evaluated the results of treatment of 36 patients with pulmonary nodules, including 27 men and 9 women aged 52 to 76 years, who were examined and treated at the Surgical Clinic of the S.M. Kirov Military Medical Academy in 2020-2023. Marking of small-diameter peripheral lung neoplasms by transthoracic use of 1% aqueous methylene blue solution made possible to detect abnormalities and lesions and perform a biopsy in 73.3% of cases. The duration of the diagnostic procedures was 30 [20-40] minutes. No postoperative complications were reported. The mean length of stay in this group of patients was 8 [6; 12] patient days. Placement of an anchor marker system allowed detection and verification of lung lesions in 95% of cases. In addition, the duration of videothoracoscopic biopsies was also 30 [20-40] minutes. No complications or deaths were reported. The mean length of stay was 7 [5; 11] patient days. The use of anchor markers to label small peripheral pulmonary nodules in the preoperative phase has some significant advantages compared with dye injection techniques, such as shorter duration of lesion mapping (p = 0.046) and less manipulation complications (p = 0.04), as well as a higher frequency of lesion detection during minimally invasive procedures. When comparing various techniques for marking pulmonary lesions, it was found that mapping of small-diameter peripheral pulmonary infiltrates using anchor markers is characterized by high performance, greater safety, facilitates intraoperative navigation for biopsy of small-diameter peripheral pulmonary neoplasms, and is superior than transthoracic use of 1% aqueous methylene blue in terms of rates of detection of pulmonary nodules during minimally invasive procedures, duration of manipulation, and complication rates.

Effect of Glass Fiber Reinforcement on Marginal Microleakage in Class II Composite Restorations: An In Vitro Pilot Study.

Background: Polymerization shrinkage of composite resins affects the marginal closure of direct dental restorations. It is responsible for developing secondary caries and indirectly affects the survival rate of restorations. This study aims to investigate the null hypothesis, which states that there are no significant differences in the marginal microleakage of Class II restorations when examined in vitro using different dental adhesives, whether the restoration material used is a composite with glass fiber reinforcement or not. Methods: Class II cavities were prepared on both proximal surfaces of thirty-six extracted human molars. A single-component (Universal VivaPen) and a two-component (Futurabond DC) self-etch adhesive system were used for the restorations in the control group (Charisma Classic) and the experimental group (Charisma Classic with Interlig glass fiber strip). An oblique layering technique and a 40-s soft-start light-curing polymerization were used. After selective pre-isolation, the specimens were placed in a 0.2% methylene blue solution and incubated at 37 °C for 24 h. The teeth were sectioned in the mesiodistal direction, and two examiners examined and graded the extent of dye penetration. Statistical analysis was conducted using the Mann-Whitney U and chi-square tests (p < 0.05). Results: All the composite restorations reinforced with glass fiber showed significantly reduced dye infiltration compared to the control group (p < 0.05). A significant difference (p < 0.05) was also observed between the two adhesives. Conclusions: The null hypothesis was rejected. Glass fiber strips significantly reduced composite restoration microleakage regardless of the adhesive. The marginal fit of the restoration was also influenced by the adhesive system used.

Alcian Blue 8GX Remediation by Fe2+/Persulfate And Heat/Persulfate

In this work, decolorization of reactive Alcain Blue 8GX dye solution were investigated by persulfate oxidation activated by ferrous ion and heat. Three different temperature (40 °C, 60 °C and 80 °C) were tested during heat activated persulfate and ferrous ion activated persulfate were tested under various molar ratios of dye:Fe2+:persulfate ratio (1:1:1, 1:2:1, 1:1:0.5, 1:4:1). In addition, pH effect has been tested at ambient conditions (5.23) and pH of 3. The results showed that increasing the temperature and persulfate concentration was favorable to the degradation of the dye with decolorization efficiency as high as 91 % observed at 80 ℃ after 90 minutes of reaction at pH 3. The ratio 1:1:1 decolorized AB 8GX 73 % at pH of 3 and 72 % at pH 5.7 after 90 minutes.

Acid Blue 113 Degradation and Mineralization by UV/Persulfate Process

In this work, decolorization of reactive Alcain Blue 8GX dye solution were investigated by persulfate oxidation activated by ferrous ion and heat. Three different temperature (40 °C, 60 °C and 80 °C) were tested during heat activated persulfate and ferrous ion activated persulfate were tested under various molar ratios of dye:Fe2+:persulfate ratio (1:1:1, 1:2:1, 1:1:0.5, 1:4:1). In addition, pH effect has been tested at ambient conditions (5.23) and pH of 3. The results showed that increasing the temperature and persulfate concentration was favorable to the degradation of the dye with decolorization efficiency as high as 91 % observed at 80 ℃ after 90 minutes of reaction at pH 3. The ratio 1:1:1 decolorized AB 8GX 73 % at pH of 3 and 72 % at pH 5.7 after 90 minutes.

Green and Eco-Friendly Egg White–TiO2 Hydrogel with Enhanced Antimicrobial, Adsorptive, and Photocatalytic Properties

The design of multi-purpose decontaminants with environmentally friendly characteristics, low cost, and high efficiency in removing pollutants from the environment is an effective and economic strategy for maintaining the long-term development of the ecosystem. Based on the strategy of killing two birds with one stone, an egg white (EW)/TiO2 hydrogel with a porous structure is devised as a bio-adsorbent using waste eggs nearing their expiration date for simultaneously achieving the efficient removal of organic dyes and the inactivation of microorganisms from industrial wastewater. The characterizations of its morphology and composition using scanning electron microscopy (SEM), the Brunauer–Emmett–Teller (BET) theory, energy-dispersive spectrometry (EDS), Fourier transform infrared spectroscopy (FTIR), and a thermogravimetric analyzer (TGA) validate the successful synthesis of EW/TiO2. The maximum adsorption capacity of EW/TiO2 is 333.172 mg∙mL−1 according to the Langmuir model. The photodegradation of a methyl blue (MB) solution under irradiation via a xenon lamp is used to assess the photocatalytic behavior of EW/TiO2. Among the different samples, the 5 wt% TiO2-doped EW/TiO2 hydrogel shows an efficiency of 99% for 120 min of irradiation. Finally, the antibacterial properties of the EW/TiO2 hydrogel are evaluated by calculating its bacterial survival rate against Escherichia coli (E. coli). The EW/TiO2 photocatalyst exhibits a photocatalytic inactivation efficiency of 90.4%, indicating that the EW/TiO2 hydrogel possesses positive antibacterial activity via effectively inhibiting the growth of the bacteria, which is suitable for industrial wastewater treatment over a long period of time.

COMPARISON OF NITROGEN-DOPED PHOTOCATALYTIC SURFACES SYNTHESIZED BY PVD AND SOL-GEL METHODS

The aim of this study was to produce photocatalytic TiO2–xNx coatings that can be active in visible light using different methods. Physical vapour deposition (PVD) and sol-gel methods were preferred for these coatings. Thin films were synthesized by dip coating on a glass substrate using the sol-gel method. In addition, thin glass film coatings were obtained by applying an arc for one minute to the glass films using the PVD method. Since the coating phase is important in terms of photoactivity, a phase analysis was performed using XRD. The obtained surfaces will be used in antibacterial applications. Therefore, the thickness of the coatings was determined with the X-Ray refraction method, and their optical band gap was measured. Based on these values, it was observed that nitrogen has a reducing effect on the optical band gap in titanium oxide-based coatings. The aim of nitrogen doping was to enhance photoactivity by adding an additional band between the valence band and conduction band of a photocatalytic surface. After these experiments using rhodamine-B and methylene blue solutions, specimens’ photocatalytic effects under fluorescent, sun and UV light were tested. It was determined that nitrogen’s decreasing effect on the optical band gap results in increased photoactivity with both PVD and sol-gel techniques. In addition, it was found that the coatings made with PVD exhibited a more controlled structure in a shorter time, while the production of sol-gel coatings was a much cheaper method, with low investment costs.

Evaluation of Microleakage in Zirconia Crown Systems Using Self-Adhesive Resin, Resin-Modified Glass Ionomer, and Glass Ionomer Cements: A Stereomicroscopic In Vitro Study

ABSTRACT Introduction: Microleakage is a critical issue impacting the success of zirconia crown restorations. This study compares the effectiveness of self-adhesive resin cement, resin-modified glass ionomer cement, and glass ionomer cement in minimizing microleakage, aiming to enhance the longevity and reliability of zirconia crowns systems. Materials and Methods: Thirty extracted premolars were collected, and all-ceramic preparation was done. Prepared teeth were randomly divided into three groups (10 each): Group A (self-adhesive resin cement), Group B (resin-modified glass ionomer cement), and Group C (glass ionomer cement). The samples underwent thermocycling, were sectioned mesiodistally and buccolingually, and submerged in a solution of methylene blue. Under a stereomicroscope, the surface of each segment was digitally imaged. A five-point grading system was used to assess microleakage. Data were statistically analyzed using two-way ANOVA, Kruskal–Wallis, and Mann–Whitney U tests (α: 0.05). Result: Microleakage with all the cement was comparable with no significant difference. The adhesive resin cement showed the least microleakage followed by resin-modified glass ionomer cement and the conventional glass ionomer cement, although insignificant. Conclusion: Resin cement, amongst all the adhesive cement, had the least microleakage; however, it was statistically insignificant.

A new and simplified extraoral approach for inferior alveolar nerve block: a cadaveric study and clinical case reports.

Inferior alveolar nerve (IAN) and lingual nerve (LN) blocks are commonly performed using the intraoral landmark techniques. However, these methods have a risk of unanticipated nerve and arterial injury or a higher failure rate. We developed a novel extraoral approach for the IAN and LN blocks, the "inferior alveolar nerve block mandibular angle approach (IANB-MA)," using ultrasound guidance. The mechanism of action of this nerve block was examined anatomically, and its clinical feasibility was reported. We performed the IANB-MA on four cadavers using different dye volumes (2, 4, 6 and 8mL). The ultrasound probe was placed on the lower edge of the mandibula of each cadaver, and the needle was advanced to the mandibular inner surface. Blue acrylic paint solution was injected, and its spread was evaluated by dissection. Our study showed that the medial pterygoid muscle fascia was stained in all cadavers. The dye reached the LN consistently, and the IAN was stained with higher volumes (6mL and 8mL). The pterygomandibular space was filled with 6mL and 8mL of the dye. The IANB-MA successfully reduced pain in three patients with trigeminal neuralgia, tongue or jaw pain. The IANB-MA is a novel ultrasound-guided approach to the IAN and the LN. The clinical feasibility and effectiveness of this technique were confirmed in our patients. It may be a good alternative analgesic approach to other conventional approaches.

Comparative Evaluation of Crack Propagation During Root Canal Preparation in Primary Molar with Manual Instrumentation, ProTaper Universal and ProTaper Next Rotary File Systems: An in vitro Study.

Root canal preparation with rotary files causes dentinal cracks in root canals of primary teeth affecting their longevity. Nickel-titanium rotary files have been widely used for root canal preparation in primary teeth. The present study compared occurrence of dentinal microcracks in root canals of extracted primary molar teeth prepared using Hedstrom (H) files, ProTaper Universal rotary files, and ProTaper Next rotary file systems. In this in vitro experimental study, 80 primary molar mesial root canals were randomly divided into four groups of 20 canals each (n=20). Group I was prepared with H files. Group II was prepared with ProTaper Universal rotary files using shaping files SX and S2. Group III was instrumented with ProTaper Next rotary files X1 and X2 while Group IV was left unprepared and served as control. Roots were stained with 1% methylene blue solution and sectioned perpendicular to the long axis at 2mm, 4mm, and 6mm from the apical foramen. Slices obtained were examined under the stereomicroscope. Data obtained were subjected to statistical analysis using chi square tests. Dentinal microcracks were observed in groups prepared using H files, ProTaper Universal, and ProTaper Next rotary files. Highest percentage of cracked root canals (20%) was seen in Group I, prepared by H files. These cracks were complete in nature, found in apical sections and statistically significant (p= 0.016). Group III prepared with ProTaper Next showed 10% dentinal cracks, followed by ProTaper Universal group with 5% cracked root canals. H files may be considered more aggressive at apical third due to complete cracks produced.

Potential increase of neurotoxic mercury risk in global blue carbon nature-based solutions

Potential increase of neurotoxic mercury risk in global blue carbon nature-based solutions

Acryloyl starch/carboxymethyl cellulose grafting copolymerization composite hydrogel for efficient adsorption of methylene blue

Abstract An efficient composite adsorbent was prepared based on acryloyl starch/carboxymethyl cellulose grafting copolymerization for the adsorptive removal of methylene blue. The developed composite hydrogels were characterized by means of FTIR, SEM (EDS-SEM), and XRD. Various parameters affecting the removal of methylene blue such as the type of adsorbents, pHs, the amount of adsorbents dosage, initial methylene blue concentration, and contact time were optimized using a series of batch adsorption experiments. The experimental data of the adsorption process were more fitted to Langmuir isotherm (R 2 = 0.9898) with a maximum adsorption capacity of 483.5 mg/g and batch kinetic experiments revealed that the adsorption process followed quasi-second-order kinetic model. The adsorption process was rapid and equilibrium was reached within 30 min. When the adsorption dosage is 0.2 g L−1, the adsorption yield for 100 mg L−1 methylene blue solution can reach 96.7 %. Therefore, acryloyl starch/carboxymethyl cellulose grafting copolymerization composite hydrogel present excellent adsorption efficiency, shows the potential application in future treatment of dyes wastewater.