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1.
ACS Appl Mater Interfaces ; 16(15): 18327-18343, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38588343

RESUMO

58S bioactive glass (BG) has effective biocompatibility and bioresorbable properties for bone tissue engineering; however, it has limitations regarding antibacterial, antioxidant, and mechanical properties. Therefore, we have developed BGAC biocomposites by reinforcing 58S BG with silver and ceria nanoparticles, which showed effective bactericidal properties by forming inhibited zones of 2.13 mm (against Escherichia coli) and 1.96 mm (against Staphylococcus aureus; evidenced by disc diffusion assay) and an increment in the antioxidant properties by 39.9%. Moreover, the elastic modulus, hardness, and fracture toughness were observed to be increased by ∼84.7% (∼51.9 GPa), ∼54.5% (∼3.4 GPa), and ∼160% (∼1.3 MPam1/2), whereas the specific wear rate was decreased by ∼55.2% (∼1.9 × 10-11 m3/Nm). X-ray diffraction, high-resolution transmission electron microscopy, and field emission scanning electron microscopy confirmed the fabrication of biocomposites and the uniform distribution of the nanomaterials in the BG matrix. The addition of silver nanoparticles in the 58S BG matrix (in BGA) increased mechanical properties by composite strengthening and bactericidal properties by damaging the cytoplasmic membrane of bacterial cells. The addition of nanoceria in 58S BG (BGC) increased the antioxidant properties by 44.5% (as evidenced by the 2,2-diphenyl-1-picrylhydrazyl assay). The resazurin reduction assay and MTT assay confirmed the effective cytocompatibility for BGAC biocomposites against mouse embryonic fibroblast cells (NIH3T3) and mouse bone marrow stromal cells. Overall, BGAC resulted in mechanical properties comparable to those of cancellous bone, and its effective antibacterial and cytocompatibility properties make it a good candidate for bone healing.


Assuntos
Cério , Nanopartículas Metálicas , Prata , Animais , Camundongos , Antioxidantes , Células NIH 3T3 , Fibroblastos , Antibacterianos/farmacologia , Vidro
2.
Med Sci Monit ; 30: e943502, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38515376

RESUMO

BACKGROUND Modification of the glass fiber post (GFP) with titanium dioxide or silver particles can improve the durability and reliability of dental treatments for ensuring long-term success. This research assessed the tensile bond strength (TBS) of an adhesive system used for cementing GFPs into root dentin following the incorporation of nanoparticles of titanium dioxide (NTiO2) and silver (NAg). MATERIAL AND METHODS Sixty human maxillary canines were prepared to create a 10-mm intra-radicular space for post placement from the cementoenamel junction. The specimens were randomly allocated into 2 groups (a non-thermocycling group and a thermocycling group). Each group was divided into 3 subgroups (10 samples each) according to the adhesive system used (adhesive system devoid of any addition, adhesive system including 1% NAg, and adhesive system infused with 1% NTiO2). TBS tests were conducted and recorded in MPa using a Universal Testing Machine, with an axial load applied at a rate of 0.5 mm/min until failure. The TBS for both groups (non-thermocycling and thermocycling) was measured in megapascals (MPa), and the failure type was recorded. The data were statistically analyzed using one-way analysis of variance (ANOVA) and Tukey's test with P.


Assuntos
Adesivos , Colagem Dentária , Vidro , Titânio , Humanos , Cimentos de Resina/química , Resistência à Tração , Reprodutibilidade dos Testes , Prata , Dentina , Teste de Materiais
3.
J Chromatogr A ; 1720: 464813, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38490142

RESUMO

Estrogens and bisphenols are typical endocrine disruptors (EDs) that pose a potential hazard to the human body due to their widespread presence in aqueous environments. In this study, a ß-cyclodextrin porous crosslinked polymer (ß-CD-PCP) was prepared in-situ on a glass fiber surface by a nucleophilic substitution reaction. An effective and sensitive solid phase microextraction method using functionalized glass fiber with ß-CD-PCP coating as the adsorbent was established for the detection of 11 EDs in a water environment. The ß-CD-PCP was in-situ prepared on a glass fiber surface by a nucleophilic substitution reaction. The ß-CD-PCP successfully separated five estrogens (ESTs) and six bisphenols (BPs) through hydrophobic and π-π interactions. The conditions affecting extraction were optimized. Under the optimized conditions, the ESTs obtained a high enrichment effect (1795-2328), low limits of detection (0.047 µg L-1) and a good linearity range (0.2-15.0 µg L-1). Furthermore, the spiked recoveries of analyte ESTs in aqueous environments were between 82.9-115.7 %. The results indicated that the prepared functionalized glass fibers exhibited good adsorption properties, and the established analytical method was reliable for monitoring trace ESTs and BPs in aqueous environments.


Assuntos
Disruptores Endócrinos , Vidro , Humanos , Disruptores Endócrinos/análise , Água/química , Microextração em Fase Sólida/métodos , Estrogênios/análise
4.
BMC Oral Health ; 24(1): 337, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491485

RESUMO

BACKGROUND: The selection of post-core material holds significant importance in endodontically treated teeth, influencing stress distribution in the dental structure after restoration. The use of computer-aided design/computer-aided manufacturing (CAD/CAM) glass fiber post-core possesses a better adaptation for different root canal morphologies, but whether this results in a more favorable stress distribution has not been clearly established. MATERIALS AND METHODS: This study employed finite element analysis to establish three models of post-core crown restoration with normal, oversized, and dumbbell-shaped root canals. The three models were restored using three different materials: CAD/CAM glass fiber post-core (CGF), prefabricated glass fiber post and resin core (PGF), and cobalt-chromium integrated metal post-core (Co-Cr), followed by zirconia crown restoration. A static load was applied and the maximum equivalent von Mises stress, maximum principal stress, stress distribution plots, and the peak of maximum displacement were calculated for dentin, post-core, crown, and the cement acting as the interface between the post-core and the dentin. RESULTS: In dentin of three different root canal morphology, it was observed that PGF exhibited the lowest von Mises stresses, while Co-Cr exhibited the highest ones under a static load. CGF showed similar stress distribution to that of Co-Cr, but the stresses were more homogeneous and concentrated apically. In oversized and dumbbell-shaped root canal remnants, the equivalent von Mises stress in the cement layer using CGF was significantly lower than that of PGF. CONCLUSIONS: In oversized root canals and dumbbell-shaped root canals, CGF has shown good performance for restoration of endodontically treated teeth. CLINICAL RELEVANCE: This study provides a theoretical basis for clinicians to select post-core materials for residual roots with different root canal morphologies and should help to reduce the occurrence of complications such as root fracture and post-core debonding.


Assuntos
Vidro , Técnica para Retentor Intrarradicular , Dente não Vital , Humanos , Coroas , Cimentos Dentários , Cimentos de Ionômeros de Vidro , Desenho Assistido por Computador , Análise do Estresse Dentário/métodos , Análise de Elementos Finitos , Resinas Compostas/química , Teste de Materiais , Estresse Mecânico
5.
Int J Mol Sci ; 25(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474252

RESUMO

Na-V-P-Nb-based materials have gained substantial recognition as cathode materials in high-rate sodium-ion batteries due to their unique properties and compositions, comprising both alkali and transition metal ions, which allow them to exhibit a mixed ionic-polaronic conduction mechanism. In this study, the impact of introducing two transition metal oxides, V2O5 and Nb2O5, on the thermal, (micro)structural, and electrical properties of the 35Na2O-25V2O5-(40 - x)P2O5 - xNb2O5 system is examined. The starting glass shows the highest values of DC conductivity, σDC, reaching 1.45 × 10-8 Ω-1 cm-1 at 303 K, along with a glass transition temperature, Tg, of 371 °C. The incorporation of Nb2O5 influences both σDC and Tg, resulting in non-linear trends, with the lowest values observed for the glass with x = 20 mol%. Electron paramagnetic resonance measurements and vibrational spectroscopy results suggest that the observed non-monotonic trend in σDC arises from a diminishing contribution of polaronic conductivity due to the decrease in the relative number of V4+ ions and the introduction of Nb2O5, which disrupts the predominantly mixed vanadate-phosphate network within the starting glasses, consequently impeding polaronic transport. The mechanism of electrical transport is investigated using the model-free Summerfield scaling procedure, revealing the presence of mixed ionic-polaronic conductivity in glasses where x < 10 mol%, whereas for x ≥ 10 mol%, the ionic conductivity mechanism becomes prominent. To assess the impact of the V2O5 content on the electrical transport mechanism, a comparative analysis of two analogue series with varying V2O5 content (10 and 25 mol%) is conducted to evaluate the extent of its polaronic contribution.


Assuntos
Nióbio , Fosfatos , Fosfatos/química , Vidro/química , Íons , Espectroscopia de Ressonância de Spin Eletrônica , Sódio/química , Cerâmica/química
6.
Med Sci Monit ; 30: e943436, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483847

RESUMO

BACKGROUND The restoration of endodontically treated teeth (ETT) and severely damaged teeth has been a concern of clinicians. Glass Fiber Post (GFPs) combine the strength of carbon fiber posts with the esthetic appearance of glass to resemble natural dentin during dental restoration procedures. This radiographical study assessed the GFP carried out by students enrolled in the Clinical Comprehensive Course at the College of Dentistry, Jazan University. MATERIAL AND METHODS A total of 32 patients treated by 18 6th-year dental students with 121 GFPs were assessed in this cross-sectional radiographic study. The assessment covered tooth type, arch, post-to-root width, length of post in relation to the crown and root lengths, amount of remaining gutta percha (GP), and gap between GP and post. Data were analyzed using SPSS, and associations between variables were determined using the chi-square test. RESULTS Maxillary teeth were the most frequently restored with posts (88.4%) with most being (58.7%) anterior teeth, and 50.4% of posts had widths that were one-third that of the root. The percentage of posts was twice (71.1%) or equal to (26.4%) the crown length, whereas two-thirds of the tested GFPs were >5 mm of the remaining GP. Significant differences were observed in location and position of teeth with post width, post length in relation to crown or root length, and amount of remaining GP, with P values of 0.018, 0.000, and 0.001, respectively. CONCLUSIONS The assessed radiographs revealed that the performance of sixth year students in accomplishment GFP radiographically was satisfactory and within the values recommended in the literature.


Assuntos
Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Humanos , Arábia Saudita , Estudantes de Odontologia , Universidades , Estudos Transversais , Vidro , Análise do Estresse Dentário
7.
Int J Prosthodont ; 37(7): 127-131, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38498864

RESUMO

PURPOSE: To evaluate and compare the fracture resistance and elastic modulus of 3D-printed post and core systems and fiber posts and composite cores. MATERIALS AND METHODS: Endodontic treatment was performed on 30 mandibular premolars, and post space preparation was performed. The teeth were then randomly divided into two groups (n = 15 per group): the 3D-printed (3DP) group and the fiber post and composite core (FPC) group. In the FPC group, fiber posts (Cytec Blanco 43.604, Hahnenkratt) were bonded with resin cement (RelyX U200, 3M), and the composite core dimension was standardized with a silicone index. In the 3DP group, the impression of the post space for each specimen was taken with pattern resin (Pattern Resin, GC America), and the coronal core was produced with the same silicone index. The impressions of the posts and cores were scanned, and then the custom post and core structures were fabricated from permanent crown resin material (Permanent Crown Resin, Formlabs) with a 3D printer (Form3B, Formlabs). Specimens were subjected to load tests with a universal testing machine (M500-25AT, Testometric). After fracture occurred, the fracture force and elastic modulus were calculated. The data were analyzed by independent sample t test (α = .05) Results: There was no statistically significant difference between the two groups in terms of peak fracture force (P = .626) and elastic modulus (P = .125), and no catastrophic root fractures were observed in either group. CONCLUSIONS: The fracture resistance of endodontically treated teeth was not significantly influenced by the post material. 3D-printed, custom-made resin posts were as effective as fiber glass posts with regard to fracture resistance.


Assuntos
Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Dente não Vital , Humanos , Resinas Compostas/química , Coroas , Vidro/química , Cimentos de Resina/química , Silicones , Impressão Tridimensional , Dente não Vital/terapia , Análise do Estresse Dentário
8.
J Mater Sci Mater Med ; 35(1): 17, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507150

RESUMO

3D borosilicate bioactive glass (1393B20 and B12.5MgSr) scaffolds were prepared by robocasting, with and without a dense layer at the top. Pore graded scaffolds are promising as they allow for membrane deposition and could limit the risk of soft tissue infiltration. In vitro dissolution was studied in tris(hydroxymethyl)aminomethane (TRIS) and Simulated Body Fluid (SBF). 1393B20 scaffolds dissolved faster than B12.5MgSr in TRIS whereas they dissolved slower in SBF. The difference in dissolution profiles, as a function of the medium used, is assigned to the different rates of precipitation of hydroxyapatite (HA). While the precipitation of calcium phosphate (CaP) in the form of HA, first sign of bioactivity, was confirmed by ICP, FTIR-ATR and SEM-EDX analysis for both compositions, 1393B20 was found to precipitate HA at a faster rate. The presence of a dense top layer did not significantly impact the dissolution rate and CaP precipitation. In vitro cell culture was performed using human adipose-derived stem cells (hADSCs). Prior to cell plating, a preincubation of 3 days was found optimum to prevent burst ion release. In direct contact, cells proliferate and spread on the scaffolds while maintaining characteristic spindle morphology. Cell plated on 1393B20 scaffolds showed increased viability when compared to cell plated on B12.5MgSr. The lower cell viability, when testing B12.5MgSr, was assigned to the depletion of Ca2+ ions from culture medium and higher pH. Static cell culture leads to believe that the scaffold produced from the 1393B20 glass composition are promising in bone regeneration applications.


Assuntos
Vidro , Tecidos Suporte , Humanos , Vidro/química , Tecidos Suporte/química , Durapatita/química , Fosfatos de Cálcio/química
9.
J Contemp Dent Pract ; 25(1): 72-78, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38514435

RESUMO

AIM: In comparing the effectiveness and efficiency of different types of post removal systems in removing different types of fiber posts (FPs), this study aims to shed light on the success of removal by currently available drill systems. MATERIALS AND METHODS: A total of 200 maxillary first molars, were root canal treated and prepared to receive posts. The molars were divided into four groups corresponding to four different FPs: Group RX, Radix FP; Group RF, Reforpost Glass Fiber; Group HI; Hi-Rem Endodontic Post; and Group DT, D.T. Light-Post Illusion X-RO. Fiber posts were done with luting by Gradia Core (GC America, Inc.). Groups were again divided into five subgroups corresponding to the technique by which the FP was removed into as follows: Subgroup P, PD-25-1.1 Drill; subgroup G, GC FP Drill; subgroup E, EasyPost Precision Drill; subgroup R, Reaccess Carbide Double Taper Kit; and subgroup H; H-Endodontic Drill. After posts were removed, effectiveness and efficiency were documented. Data were tabulated and statistically analyzed. RESULTS: Strong significant differences regarding efficiency among groups (FP type) and subgroups (drills used) (p = 0.00) were shown by the one-way analysis of variance (ANOVA) test. Subgroup DT-G scored the longest mean removal time (20.9 minutes) while Subgroup RX-R scored the shortest mean removal time (1.4 minutes) Regarding effectiveness, strong significant differences among groups (p = 0.00) and subgroups (p = 0.00) were shown by one-way ANOVA. Subgroup RF-G scored the highest scale (5.2) whereas subgroup HI-R scored the lowest mean scale (1.2). CONCLUSION: The difference was strongly significant between tested post-removal kits and between tested FPs. Re-access Carbide Double Taper Kit performed superiorly in both effectiveness and efficiency, followed by PD-25-1.1 Drill. Hi-Rem post showed the best retrieving results among other FPs. CLINICAL SIGNIFICANCE: Knowing the best technique and tools for post removal could spare the practitioner any unwanted complications during post removal. How to cite this article: Sayed M, Alahmad AM, Alhajji KS, et al. Removal Efficiency and Effectiveness of Four Different Fiber Posts Using Five Different Drill Systems in Multirooted Teeth. J Contemp Dent Pract 2024;25(1):72-78.


Assuntos
Técnica para Retentor Intrarradicular , Dente não Vital , Humanos , Tratamento do Canal Radicular , Dente não Vital/terapia , Vidro , Teste de Materiais , Cimentos de Resina , Análise do Estresse Dentário
10.
J Photochem Photobiol B ; 253: 112878, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447252

RESUMO

PURPOSE: To investigate the influence of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) and calcium hydroxide (CH) medication on the mechanical characteristics, degree of conversion (DC), quantification, and volume of gaps at the adhesive interface of glass fiber posts (GFPs) luted to distinct thirds of root canal dentin. Additionally, the microhardness (MH), elastic modulus (Eit), morphology, and chemical structure of the intraradicular dentin were assessed. MATERIALS AND METHODS: 6 experimental groups were formed by sorting 102 bovine incisors. Canals receiving deionized water irrigation as a negative control; canals receiving deionized water irrigation and filled with CH as a positive control; groups treated with CH + MB at 50 and 100 mg/L without irradiation; and groups treated with CH + MB at 50 and 100 mg/L irradiated by red laser for 60 s (660 nm; 100 mW; 6.5 J; 72 J/cm2). MH, Eit, and DC properties were evaluated for both the resin cement layer and root dentin substrate (n = 8). Volume and quantification of gaps at the bonding interface (n = 6), and dentin morphology and chemical content were investigated (n = 3). Data were analyzed using a repeated-measures 2-way ANOVA followed by Tukey post hoc analysis (α = 0.05). RESULTS: The distinct intraradicular thirds and treatment with MB-mediated aPDT, whether activated or not, in combination with CH, had a significant impact on the mechanical characteristics of the root dentin. This effect was also observed in the MH, Eit, DC, quantification, and volume of gaps at the luting interface (P < .05). In general, a higher concentration of MB, whether activated by a red laser or not, led to lower values in the mechanical properties of the root dentin, as well as in MH, Eit, and DC at the adhesive interface (P < .05). Additionally, these groups exhibited higher values for quantification and volume of gaps at the luting substrate (P < .05). Scanning electron micrographs and energy dispersive X-ray spectra showed qualitative similarity among all groups, except for the negative experimental control group. CONCLUSIONS: MB-mediated aPDT at 50 mg/L, in combination with CH, demonstrated favorable physico-chemical and mechanical characteristics in intraradicular dentin, along with satisfactory mechanical features and the adhesive interface integrity for GFPs at all intraradicular depths. CLINICAL SIGNIFICANCE: MB-mediated aPDT at a concentration of 50 mg/L combined to CH medication represents a suitable choice for photosensitization in the context of intracanal disinfection following the biomechanical procedure and prior to luting of intraradicular restorations.


Assuntos
Anti-Infecciosos , Vidro , Fotoquimioterapia , Animais , Bovinos , Fármacos Fotossensibilizantes/farmacologia , Hidróxido de Cálcio/farmacologia , Azul de Metileno/farmacologia , Cavidade Pulpar , Fotoquimioterapia/métodos , Dentina , Água , Teste de Materiais
11.
MMW Fortschr Med ; 166(4): 34, 2024 03.
Artigo em Alemão | MEDLINE | ID: mdl-38453854
12.
Anal Chim Acta ; 1297: 342336, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38438226

RESUMO

BACKGROUND: Developing disposable paper-based devices has positively impacted analytical science, particularly in developing countries. Some benefits of those devices include their versatility, affordability, environmentally friendly, and the possibility of being integrated with portable electrochemical or colorimetric detectors. Paper-based analytical devices (PADs) comprising circular zones and microfluidic networks have been successfully employed in the analytical chemistry reign. However, the combination of the stencil-printing method and alternative binder has not been satisfactorily explored for fabricating colorimetric paper devices. RESULTS: We developed PADs exploring the stencil printing approach and glass varnish as the hydrophobic chemical agent. As a proof-of-concept, the colorimetric assay of salivary α-amylase (sAA) was performed in saliva samples. Through the scanning electron microscopy measurements, it was possible to indicate satisfactory definitions between native fibers and barrier, and that the measured values for the channel width revealed suitable fidelity (R2 = 0.99) with the nominal widths (ranging from 400 to 5000 µm). The proposed hydrophobic barrier exhibited excellent chemical resistance. The analytical applicability for detecting sAA revealed linear behavior in the range from 2 to 12 U mL-1 (R2 = 0.99), limit of detection of 0.75 U mL-1, reproducibility (RSD ≤2.4%), recovery experiments ranged from 89 to 108% and AGREE response (0.86). In addition, the colorimetric analysis of sAA in four different saliva samples demonstrated levels ranging from 202 to 2080 U mL-1, which enabled monitoring the absence and presence of periodontitis. SIGNIFICANCE: This report has presented the first use of a self-adhesive mask and glass varnish for creating circular zones and microfluidic architectures on paper without using thermic or UV curing treatments. Also, the proposed analytical methodology for detecting sAA exhibited suitable ecological impact considering the AGREE tool. We believe the proposed fabrication of paper devices emerges as a novel, simple, high-fidelity microfluidic channel and portable analytical approach for colorimetric sensing.


Assuntos
Colorimetria , alfa-Amilases Salivares , Reprodutibilidade dos Testes , Bioensaio , Vidro
13.
Biomacromolecules ; 25(4): 2348-2357, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38499398

RESUMO

Covalent adaptable networks (CANs) are being developed as future replacements for thermosets as they can retain the high mechanical and chemical robustness inherent to thermosets but also integrate the possibility of reprocessing after material use. Here, covalent adaptable polyimine-based networks were designed with methoxy and allyloxy-substituted divanillin as a core component together with long flexible aliphatic fatty acid-based amines and a short rigid chain triamine, yielding CANs with a high renewable content. The designed series of CANs with reversible imine functionality allowed for fast stress relaxation and tailorability of the thermomechanical properties, as a result of the ratio between long flexible and short rigid amines, with tensile strength (σb) ranging 1.07-18.7 MPa and glass transition temperatures ranging 16-61 °C. The CANs were subsequently successfully reprocessed up to three times without determinantal structure alterations and retained mechanical performance. The CANs were also successfully chemically recycled under acidic conditions, where the starting divanillin monomer was recovered and utilized for the synthesis of a recycled CAN with similar thermal and mechanical properties. This promising class of thermosets bearing sustainable dynamic functionalities opens a window of opportunity for the progressive replacement of fossil-based thermosets.


Assuntos
Aminas , Ácidos Graxos , Vidro , Iminas , Temperatura
14.
Braz Dent J ; 35: e245833, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537024

RESUMO

The aim was to evaluate the effect of stress distribution on vertical, horizontal, and oblique forces on the tooth model after reattaching the fragments of the maxillary incisor with vertical root fracture (VRF) using different materials, by 3D finite element analysis (FEA). Tooth with a root canal, spongious, and cortical bone models were designed. VRF was modeled on a tooth with 4 different re-attachment models: Group 1: dual-cure cement (DC)+fiber reinforced composite (FRC), Group 2: DC+polyethylene fiber, Group 3: DC+glass fiber, and Group 4:DC. 100 N force was applied in 3 different directions. Maximum principal stresses (σmax) of dentin, and re-attachment materials were evaluated on colored images. The highest σmax values ​​were on the repair materials under vertical forces for Groups 1 and 4, respectively; Groups 2 and 3 showed similarity. The highest σmax values in repair materials under horizontal and oblique forces were observed in Group 3 however the lowest σmax values in repair materials under oblique and horizontal forces were observed in Group 1. The stress values ​​on repair materials gradually increased respectively starting from horizontal to vertical. As the elasticity modulus of the repair materials increased, the stress values ​​on root dentin increased. Through all force directions, except vertical forces, lower stress values were observed with FRC. The fracture resistance was bigger when using solely FRC or dual-cure resin cement in comparison to fiber-supported designs. Adding polyethylene fiber to re-restorations decreased stress values ​​compared to glass fiber addition. Therefore, when adding fibers, polyethylene fiber will be advantageous.


Assuntos
Materiais Dentários , Técnica para Retentor Intrarradicular , Resinas Compostas , Cavidade Pulpar , Análise de Elementos Finitos , Polietileno , Estresse Mecânico , Teste de Materiais , Análise do Estresse Dentário , Vidro
15.
Int J Mol Sci ; 25(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542533

RESUMO

Proteomic analysis of extracellular vesicles presents several challenges due to the unique nature of these small membrane-bound structures. Alternative analyses could reveal outcomes hidden from standard statistics to explore and develop potential new biological hypotheses that may have been overlooked during the initial evaluation of the data. An analysis sequence focusing on deviating protein expressions from donors' primary cells was performed, leveraging machine-learning techniques to analyze small datasets, and it has been applied to evaluate extracellular vesicles' protein content gathered from mesenchymal stem cells cultured on bioactive glass discs doped or not with metal ions. The goal was to provide additional opportunities for detecting details between experimental conditions that are not entirely revealed with classic statistical inference, offering further insights regarding the experimental design and assisting the researchers in interpreting the outcomes. The methodology extracted a set of EV-related proteins whose differences between conditions could be partially explainable with statistics, suggesting the presence of other factors involved in the bioactive glasses' interactions with tissues. Outlier identification of extracellular vesicles' protein expression levels related to biomaterial preparation was instrumental in improving the interpretation of the experimental outcomes.


Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Proteômica/métodos , Vesículas Extracelulares/metabolismo , Vidro
16.
Luminescence ; 39(3): e4714, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506395

RESUMO

In this study, the melt quenching approach is used to synthesize a lead borate-strontium-based glass system doped with samarium ions. Modifications in the glass network structure arising from the addition of various concentrations of Sm3+ ions were investigated via Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed B-O-B bridges, BO3 , and BO4 units are present. UV-vis-NIR spectroscopic measurement was performed to study the optical absorption spectra. Optical constants such as optical bandgap energies, refractive indices, and other related parameters were evaluated. The lifetime fluorescence decay was measured and ranged between 1.04 and 1.88 ns. The photoluminescence spectra in the range 500-750 nm revealed four transitions from the ground state 6 G5/2 to the excited states 6 H5/2 , 6 H7/2 , 6 H9/2 and 6 H11/2 and J-O theory was utilized to study these optical transitions for Sm3+ ions. Calculations of the oscillator strengths and J-O intensity parameters were performed and the obtained J-O parameters followed the sequence Ω4 > Ω6 > Ω2 . The ratio O/R indicated a high lattice asymmetry around the samarium ions. The values of lifetimes and branching ratios for the fabricated samples emphasized their suitability to be used in laser applications. The current glass samples are good candidates for orange and red emission devices.


Assuntos
Boratos , Tungstênio , Boratos/química , Samário/química , Íons , Vidro/química
17.
Nat Commun ; 15(1): 1631, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388545

RESUMO

Metasurfaces have exhibited unprecedented degree of freedom in manipulating electromagnetic (EM) waves and thus provide fantastic front-end interfaces for smart systems. Here we show a framework for perception enhancement based on vision-driven metasurface. Human's eye movements are matched with microwave radiations to extend the humans' perception spectrum. By this means, our eyes can "sense" visual information and invisible microwave information. Several experimental demonstrations are given for specific implementations, including a physiological-signal-monitoring system, an "X-ray-glasses" system, a "glimpse-and-forget" tracking system and a speech reception system for deaf people. Both the simulation and experiment results verify evident advantages in perception enhancement effects and improving information acquisition efficiency. This framework can be readily integrated into healthcare systems to monitor physiological signals and to offer assistance for people with disabilities. This work provides an alternative framework for perception enhancement and may find wide applications in healthcare, wearable devices, search-and-rescue and others.


Assuntos
Movimentos Oculares , Olho , Humanos , Simulação por Computador , Vidro , Percepção
18.
Waste Manag ; 177: 196-202, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38330515

RESUMO

The delamination of layers of waste solar panels remains a major challenge due to the lack of effective solutions for removing the adhesive between layers. In this study, a novel efficient method for disengagement of glass from the rest of the module is introduced, in which only water is used under high pressure (<3 MPa) and relatively low temperatures (230-250 °C) in a hydrothermal reactor, allowing for facile separation of the glass from the interlayer. The other layers of the module can also easily be peeled apart in subsequent processes. The separated glass is free of metals and polymers that can be utilized directly for further applications. The benefits of this method include no use of chemicals, preservation of the recovered materials' quality (i.e., interlayers, Si sheet, and glass), relatively low-temperature operation, no hazardous gas generation, and reduced energy consumption. A pilot scale design of the method has been proposed for processing a full panel, demonstrating its industrial viability.


Assuntos
Temperatura Baixa , Vidro , Indústrias , Polímeros , Água
19.
Pharm Res ; 41(3): 547-556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38326531

RESUMO

OBJECTIVE: This study aimed to investigate the movement of liquid in the needle region of staked-in-needle pre-filled syringes using neutron imaging and synchrotron X-ray tomography. The objective was to gain insights into the dynamics of liquid presence and understand the factors contributing to needle clogging. METHODS: Staked-in-needle pre-filled syringes were examined using neutron radiography and synchrotron X-ray phase-contrast computed tomography. Neutron radiography provided a 2D visualization of liquid presence in the needle, while synchrotron X-ray tomography offered high-resolution 3D imaging to study detailed morphological features of the liquid. RESULTS: Neutron radiography revealed liquid presence in the needle region for as-received samples and after temperature and pressure cycling. Pressure cycling had a more pronounced effect on liquid formation. Synchrotron X-ray tomography confirmed the presence of liquid and revealed various morphologies, including droplets of different sizes, liquid segments blocking sections of the needle, and a thin layer covering the needle wall. Liquid presence was also observed between the steel needle and the glass barrel. CONCLUSIONS: The combination of neutron imaging and synchrotron X-ray tomography provided valuable insights into the dynamics of liquid movement in staked-in-needle pre-filled syringes. Temperature and pressure cycling were found to contribute to additional liquid formation, with pressure changes playing a significant role. The detailed morphological analysis enhanced the understanding of microstructural arrangements within the needle. This research contributes to addressing the issue of needle clogging and can guide the development of strategies to improve pre-filled syringe performance.


Assuntos
Agulhas , Tomografia Computadorizada por Raios X , Pressão , Temperatura , Vidro/química
20.
J Pediatr Orthop ; 44(5): 327-332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38329338

RESUMO

INTRODUCTION: We conducted a randomized controlled trial comparing fiberglass short leg casts with traditional cast padding to similar casts with water-resistant cast padding and recorded the opinion of the patient/caregiver and Orthopaedic Technicians (Ortho Techs) that applied and removed the casts. METHODS: Subjects with an injury that would be treated with a short leg cast were enrolled and randomized into a traditional cast or a water-resistant cast. Following cast application, the Ortho Tech that applied the cast completed a questionnaire asking their opinion on ease of application, moldability, padding level, and time taken for application. Following the removal of the study cast, the Ortho Tech that removed the cast completed a questionnaire that included an assessment of skin condition and evidence of the patient poking items inside the cast, as well as their opinion of ease of padding removal, padding durability and longevity, and an overall quality assessment of the cast padding. Following cast removal, the patient (or caregiver) also completed a questionnaire asking for their assessment of comfort, the weight of the cast, itchiness, heat/sweat, smell, and satisfaction. Patients who were treated with an expanded polytetrafluoroethylene cast were also asked about their happiness with the cast's water resistance and asked how long the cast took to dry. RESULTS: Sixty patients were included in this study, thirty in each group. The water-resistant casts took longer to apply than the traditional casts (12.4±4.0 vs. 8.2±3.2 min, P <0.001). The Ortho Techs favored the traditional cast when it came to ease of application ( P <0.001), moldability ( P =0.003), ease of padding removal ( P <0.001), padding durability ( P =0.006), padding longevity ( P =0.005), and their overall impression ( P =0.014). The patients/caregivers responded similarly among the 2 groups for each survey question. CONCLUSIONS: Patients randomized into each cast type tolerated their cast similarly; however, the Ortho Techs involved in this study preferred the traditional cast.


Assuntos
Perna (Membro) , Água , Humanos , Projetos Piloto , Moldes Cirúrgicos/efeitos adversos , Vidro
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