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Sabe-se que para uma restauração ser considerada um sucesso clínico é preciso que haja uma concomitância saudável entre a estrutura dentária, o material restaurador e as estruturas biológicas periodontais. As restaurações transcirúrgicas caracterizam-se como procedimentos alternativos para possibilitar a restauração de dentes com cárie dentária extensa, restaurações subgengivais desadaptadas e fraturas. O presente estudo teve como objetivo realizar um relato de caso de um procedimento cirúrgico-restaurador, através de uma técnica de restauração transcirúrgica. Este estudo tem como justificativa relatar um caso clínico, colaborando com maiores informações sobre a escolha da técnica a ser empregada, mostrando em quais situações devemos escolher uma restauração transcirúrgica e quais seus benefícios. Também, salientar se devemos fazer a recuperação do espaço biológico do periodonto ou não(AU)
It is known that for a restoration to be considered a clinical success, there must be a healthy concomitance between the tooth structure, the restorative material and the periodontal biological structures. Transsurgical restorations are characterized as alternative procedures to enable the restoration of teeth with extensive dental caries, maladapted subgingival restorations and fractures. The present study aims to carry out a case report of a surgical-restorative procedure, using a transsurgical restoration technique. This study is justified by reporting a clinical case, providing more information on the choice of technique to be used, showing in which situations we should choose a transsurgical restoration and what its benefits are. Also, highlight whether we should recover the biological space of the periodontium or not(AU)
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Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Bucais , Restauração Dentária PermanenteRESUMO
The functional and sensory augmentation of living structures, such as human skin and plant epidermis, with electronics can be used to create platforms for health management and environmental monitoring. Ideally, such bioelectronic interfaces should not obstruct the inherent sensations and physiological changes of their hosts. The full life cycle of the interfaces should also be designed to minimize their environmental footprint. Here we report imperceptible augmentation of living systems through in situ tethering of organic bioelectronic fibres. Using an orbital spinning technique, substrate-free and open fibre networks-which are based on poly (3,4-ethylenedioxythiophene):polystyrene sulfonate-can be tethered to biological surfaces, including fingertips, chick embryos and plants. We use customizable fibre networks to create on-skin electrodes that can record electrocardiogram and electromyography signals, skin-gated organic electrochemical transistors and augmented touch and plant interfaces. We also show that the fibres can be used to couple prefabricated microelectronics and electronic textiles, and that the fibres can be repaired, upgraded and recycled.
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Despite the substantial advancement in developing various hydrogel microparticle (HMP) synthesis methods, emulsification through porous medium to synthesize functional hybrid protein-polymer HMPs has yet to be addressed. Here, the aided porous medium emulsification for hydrogel microparticle synthesis (APME-HMS) system, an innovative approach drawing inspiration from porous medium emulsification is introduced. This method capitalizes on emulsifying immiscible phases within a 3D porous structure for optimal HMP production. Using the APME-HMS system, synthesized responsive bovine serum albumin (BSA) and polyethylene glycol diacrylate (PEGDA) HMPs of various sizes are successfully synthesized. Preserving protein structural integrity and functionality enable the formation of cytochrome c (cyt c) - PEGDA HMPs for hydrogen peroxide (H2O2) detection at various concentrations. The flexibility of the APME-HMS system is demonstrated by its ability to efficiently synthesize HMPs using low volumes (≈50 µL) and concentrations (100 µm) of proteins within minutes while preserving proteins' structural and functional properties. Additionally, the capability of the APME-HMS method to produce a diverse array of HMP types enriches the palette of HMP fabrication techniques, presenting it as a cost-effective, biocompatible, and scalable alternative for various biomedical applications, such as controlled drug delivery, 3D printing bio-inks, biosensing devices, with potential implications even in culinary applications.
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OBJECTIVE: This article puts forward consensus recommendations from PROSEC North America regarding single indirect restorations made from ceramic and nonmetallic biomaterials in posterior teeth. OVERVIEW: The consensus process involved a multidisciplinary panel and three consensus workshops. A systematic literature review was conducted across five databases to gather evidence. The recommendations, informed by findings from systematic reviews and formulated based on a two-phase e-Delphi survey, emphasize a comprehensive treatment strategy that includes noninvasive measures alongside restorative interventions for managing dental caries and tooth wear. The recommendations advocate for selecting between direct and indirect restorations on a case-by-case basis, favoring inlays and onlays over crowns to align with minimally invasive dentistry principles. The recommendations highlight the critical role of selecting restorative biomaterials based on clinical performance, esthetic properties, and adherence to manufacturer guidelines. They emphasize the importance of precision in restorative procedures, including tooth preparation, impression taking, contamination control, and luting. Regular follow-up and maintenance tailored to individual patient needs are crucial for the longevity of ceramic and nonmetallic restorations. CONCLUSIONS: These PROSEC recommendations provide a framework for dental practitioners to deliver high-quality restorative care, advocating for personalized treatment planning and minimally invasive approaches to optimize oral health outcomes. CLINICAL SIGNIFICANCE: The PROSEC North America recommendations highlight the importance of minimally invasive techniques in posterior tooth restorations using ceramic and non-metallic biomaterials. These principles prioritize tooth structure conservation and personalized treatment planning, essential for enhancing clinical outcomes and long-term oral health.
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This investigation presents a critical analysis of mouthguard production, focusing on the evaluation of conventional vs additive manufacturing methods, the materials involved, and aspects such as their failure and prevention. It also summarizes the current trends, perspectives, and the main limitations. It is shown that some of the shortcomings can be solved by implementing additive manufacturing technologies, which are systematically reviewed in this research. Due to the specific materials used to produce mouthguards, there are certain additive manufacturing technologies that dominate and a wide variety of raw materials. The costs vary depending on the technology.
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We characterize the subsurface thermal degradation of an inert analog of high-explosive molecular crystals (Eu:Y(acac)3(DPEPO)) (EYAD) embedded inside of a plastic bonded explosive simulant using feedback-assisted wavefront shaping-based fluorescence and Raman spectroscopies. This technique utilizes wavefront shaping to focus pump light inside a heterogeneous material onto a target particle, which significantly improves its spectroscopic signature. We find that embedding the EYAD crystals in the heterogeneous polymer results in improved thermal stability, relative to bare crystal measurements, with the crystal remaining fluorescent to >612 K inside of the heterogeneous material, while the bare crystal's fluorescence is fully quenched by 500 K. We hypothesize that this improvement is due to the polymer restricting the effects of EYAD melting, which occurs at 400 K and is the primary mechanism for spectroscopic changes in the temperature range explored.
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Severe bleeding and bacterial infections pose significant challenges to the global public health. Effective hemostatic materials have the potential to be used for rapid control of bleeding at the wound site. In this study, mesoporous silica nanoparticles (MSN) were doped with zinc ions (MSN@Zn) and subsequently functionalized with carboxyl (-COOH) groups through post-grafting, resulting in (MSN@Zn-COOH). The results demonstrated the successful functionalization of carboxyl groups on the surface of MSN@Zn mesoporous materials with minimal impact on the morphology. The released zinc ions showed potent antibacterial activity (above â¼80â¯%) against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In vitro and in vivo assessments of MSN@Zn-COOH revealed excellent hemostatic effects and favorable blood compatibility. Hemolysis percentages associated with MSN@Zn-COOH exhibited noteworthy reductions in comparison to MSN. Furthermore, a decrease in APTT (a test evaluating the intrinsic coagulation pathway) of modified MSN@Zn indicated enhanced hemostasis, supported by their negative zeta potential (â¼ -14 to -43â¯mV). Importantly, all samples showed no cytotoxicity. This work underscores the potential of MSN@Zn-COOH, with its combined hemostatic performance and antibacterial activity, for emergency clinical applications.
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High entropy material (HEM) has emerged as an appealing material platform for various applications, and specifically, the electrochemical performances of HEM could be further improved through self-assembled structure design. However, it remains a big challenge to construct such high-entropy self-assemblies primarily due to the compositional complexity. Herein, we propose a bottom-up directional freezing route to self-assemble high-entropy hydrosols into porous nanosheets. Taking Prussian blue analogue (PBA) as an example, the simultaneous coordination-substitution reactions yield stable high-entropy PBA hydrosols. During subsequent directional freezing process, the anisotropic growth of ice crystals could guide the two-dimensional confined assembly of colloidal nanoparticles, resulting in high-entropy PBA nanosheets (HE-PBA NSs). Thanks to the high-entropy and self-assembled structure design, the HE-PBA NSs manifests markedly enhanced sodium storage kinetics and performances in comparison with medium/low entropy nanosheets and high entropy nanoparticles.
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OBJECTIVE: To formulate an experimental methacrylate-based photo-polymerizable resin for 3D printing with ytterbium trifluoride as filler and to evaluate the mechanical, physicochemical, and biological properties. METHODS: Resin matrix was formulated with 60 wt% UDMA, 40 wt% TEGDMA, 1 wt% TPO, and 0.01 wt% BHT. Ytterbium Trifluoride was added in concentrations of 1 (G1 %), 2 (G2 %), 3 (G3 %), 4 (G4 %), and 5 (G5 %) wt%. One group remained without filler addition as control (GC). The samples were designed in 3D builder software and printed using a UV-DLP 3D printer. The samples were ultrasonicated with isopropanol and UV cured for 60 min. The resins were tested for degree of conversion (DC), flexural strength, Knoop microhardness, softening in solvent, radiopacity, colorimetric analysis, and cytotoxicity (MTT and SRB). RESULTS: Post-polymerization increased the degree of conversion of all groups (p < 0.05). G2 % showed the highest DC after post-polymerization. G2 % showed no differences in flexural strength from the G1 % and GC (p > 0.05). All groups showed a hardness reduction after solvent immersion. No statistical difference was found in radiopacity, softening in solvent (ΔKHN%), colorimetric spectrophotometry, and cytotoxicity (MTT) (p > 0.05). G1 % showed reduced cell viability for SRB assay (p < 0.05). SIGNIFICANCE: It was possible to produce an experimental photo-polymerizable 3D printable resin with the addition of 2 % ytterbium trifluoride as filler without compromising the mechanical, physicochemical, and biological properties, comparable to the current provisional materials.
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The clinical failure mode of dental crown ceramics involves radial cracking at the interface, driven by the surface tension generated from the flexure of the ceramic layer on the subsurface. This results in a reduced lifespan for most all-ceramic dental crowns. Therefore, investigating optimal material combinations to reduce stress concentration in dental crown materials has become crucial for future successful clinical applications. The anisotropic complex structures of natural materials, such as nacre, could potentially create suitable strong and damage-resistant materials. Their imitation of natural structural optimisation and mechanical functionality at both the macro- and micro-levels minimises weaknesses in dental crowns. This research aims to optimise cost-effective, freeze-casted bioinspired composites for the manufacture of novel, strong, and tough ceramic-based dental crowns. To this end, multilayer alumina (Al2O3) composites with four different polymer phases were tested to evaluate their bending behaviour and determine their flexural strength. A computational model was developed and validated against the experimental results. This model includes Al2O3 layers that undergo gentle compression and distribute stress, while the polymer layers act as stress relievers, undergoing plastic deformation to reduce stress concentration. Based on the experimental data and numerical modelling, it was concluded that these composites exhibit variability in mechanical properties, primarily due to differences in microstructures and their flexural strength. Furthermore, the findings suggest that bioinspired Al2O3-based composites demonstrate promising deformation and strengthening behaviour, indicating potential for application in the dental field.
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Phase change materials (PCMs) are crucial for sustainable thermal management in energy-efficient construction and cold chain logistics, as they can store and release renewable thermal energy. However, traditional PCMs suffer from leakage and a loss of formability above their phase change temperatures, limiting their shape stability and versatility. Inspired by the muscle structure, formable PCMs with a hierarchical structure and solvent-responsive supramolecular networks based on polyvinyl alcohol (PVA)/wood composites are developed. The material, in its hydrated state, demonstrates low stiffness and pliability due to the weak hydrogen bonding between aligned wood fibers and PVA molecules. Through treatment of poly(ethylene glycol) (PEG) into the PVA/wood PEG gel (PEG/PVA/W) with strengthened hydrogen bonds, the resulting wood-based PCMs in the hard and melting states elevate the tensile stress from 10.14 to 80.86 MPa and the stiffness from 420 MPa to 4.8 GPa, making it 530 times stiffer than the PEG/PVA counterpart. Capable of morphing in response to solvent changes, these formable PCMs enable intricate designs for thermal management. Furthermore, supported by a comprehensive life cycle assessment, these shape-adaptable, recyclable, and biodegradable PCMs with lower environmental footprint present a sustainable alternative to conventional plastics and thermal management materials.
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INTRODUCTION: Cephalic arch stenosis (CAS) is often recurrent, resistant to treatment and the intervention outcome is not well validated so far. We purposed to assess the clinical outcomes of CAS treatment in patients with hemodialysis access. METHODS: Electronic bibliographic sources were searched up to December 4 2023 to identify studies reported outcome after treating CAS. Direct and indirect evidence was combined to compare odds ratios (OR) and surfaces under the cumulative ranking curves across the different treatment modalities through meta-analysis and network meta-analyses (NMA). This systematic review was conducted in accordance with the PRISMA-P. The review is registered in PROSPERO (CRD42022296513). RESULTS: Four randomized controlled trials (RCTs) and 15 non-RCTs were included in the analysis. The study population differed in fistula type, restenosis or thrombosis, and significant heterogeneity was observed among the publications. The risk of bias was low to serious. Meta-analysis found no significant difference between DCB and PTA in primary patency at 6 and 12 months (OR 1.16 and 0.60, respectively; low certainty of evidence). Favorable result with STG compared to stent or PTA at 3, 6, and 12 month was observed (OR 4.28, 5.13, and 13.12, and 4.28, 5.13, 13.12, respectively; low certainty of evidence). Regarding primary patency, the treatment rankings, from highest to lowest, were STG (92.7%), transposition (76.0%), stent (67.5%), DCB (46.3%), and PTA (64.5%) at 12 months. CONCLUSION: Despite data limitations, the low-quality evidence suggests that STG may merit consideration as a primary treatment option when all alternatives are applicable, given their potential for better primary patency and higher treatment ranking.
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Diffusion processes govern fundamental phenomena such as phase transformations, doping, and intercalation in van der Waals (vdW) bonded materials. Here, the diffusion dynamics of W atoms by visualizing the motion of individual atoms at three different vdW interfaces: hexagonal boron nitride (BN)/vacuum, BN/BN, and BN/WSe2, by recording scanning transmission electron microscopy movies is quantified. Supported by density functional theory (DFT) calculations, it is inferred that in all cases diffusion is governed by intermittent trapping at electron beam-generated defect sites. This leads to diffusion properties that depend strongly on the number of defects. These results suggest that diffusion and intercalation processes in vdW materials are highly tunable and sensitive to crystal quality. The demonstration of imaging, with high spatial and temporal resolution, of layers and individual atoms inside vdW heterostructures offers possibilities for direct visualization of diffusion and atomic interactions, as well as for experiments exploring atomic structures, their in situ modification, and electrical property measurements of active devices combined with atomic resolution imaging.
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Understanding the mechanical properties of porous carbon-based materials can lead to advancements in various applications, including energy storage, filtration, and lightweight structural components. Also, investigating how silicon doping affects these materials can help optimize their mechanical properties, potentially improving strength, durability, and other performance metrics. This research investigated the effects of atomic doping (Si particle up to 10 %) on the mechanical properties of the porous carbon matrix using molecular dynamics methods. Young's modulus, ultimate strength, radial distribution function, interaction energy, mean square displacement and potential energy of designed samples were reported. MD outputs predict the Si doping process improved the mechanical performance of porous structures. Numerically, Young's modulus of the C-based porous matrix increased from 234.33 GPa to 363.82 GPa by 5 % Si inserted into a pristine porous sample. Also, the ultimate strength increases from 48.54 to 115.93 GPa with increasing Si doping from 1 % to 5 %. Silicon doping enhances the bonding strength and reduces defects in the carbon matrix, leading to improved stiffness and load-bearing capacity. This results in significant increases in mechanical performance. However, excess Si may disrupt the optimal bonding network, leading to weaker connections within the matrix. Also, considering the negative value of potential energy in different doping percentages, it can be concluded that the amount of doping added up to 10 % does not disturb the initial structure and stability of the system, and the structure still has structural stability. So, we expected our introduced atomic samples to be used in actual applications.
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BACKGROUND: Gonadal dysgenesis, a genetic condition characterized by incomplete of defective formation of the gonads, can present with vaginal agenesis in individuals with 46,XY karyotype. CASE: We report an innovative intervention in the management of vaginal agenesis in a 19-year-old female with gonadal dysgenesis. Despite initial attempts with vaginal dilators, the patient presented unresponsive, leading to the adoption of a neovaginoplasty using Nile Tilapia Fish Skin (NTFS) as graft. The procedure, based on the McIndoe technique, involved the creation of a 10cm x 3cm vaginal canal with an NTFS-wrapped acrylic mold without complications. DISCUSSION: The use of NTFS as a graft for neovaginoplasty in gonadal dysgenesis, a novel approach not previously reported in medical literature for this diagnosis, demonstrated favorable outcomes in terms of functionality and patient well-being.
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The addition of polymer fibers to cemented paste backfill (CPB) has shown promise in enhancing mechanical properties, although it also introduces changes in rheological characteristics. This study aimed to investigate the influence of different types of polymer fibers, namely virgin commercial polypropylene fiber (CPPF), recycled tire polymer fiber (RTPF), and recycled tire rubber fiber (RF), on the rheological properties of CPB mixtures through an experimental program, and provide design references for CPB pipeline transport. The results revealed consistent reductions in bulk density upon the incorporation of polymer fibers into CPB, alongside varying impacts on slump. Specifically, the addition of CPPF had a mild effect, while RTPF caused a continuous decrease in slump, and RF exhibited minimal influence up to a 4% concentration, with substantial effects thereafter. Moreover, the inclusion of fibers led to increases in apparent viscosity parameters, with RTPF inducing the most significant changes, followed by varying responses from CPPF and RF. When using RTPF for CPB reinforcement, emphasis should be placed on enhancing technical indicators related to viscosity such as energy consumption and pipeline wear during pipeline transport. Furthermore, adjustments were necessary to account for flow curve instability resulting from interactions between fibers and the paddle, with the data aligning well with the Bingham model. The addition of fibers, particularly CPPF and RF, primarily influenced plastic viscosity rather than yield stress, underscoring the limitations of slump tests in assessing rheology.
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OBJECTIVES: To assess the evolution of continuing medical education/continuous professional development (CME/CPD) in European Radiology with a particular focus on on-site (live educational events, LEE) vs remote (electronic learning materials, ELM) participation and the impact of the COVID-19 pandemic. METHODS: Results related to CME/CPD of surveys conducted by the Accreditation Council of Imaging (ACI) between 2017 and 2020 are summarized. Additional insights from the survey conducted in spring 2023, exploring online education trends since the start of the COVID-19 pandemic, are presented. Finally, the results of the surveys are correlated with the total number of CME/CPD applications received annually from 2018 to 2022. RESULTS: Pre-pandemic, 90% of European radiologists supported mandatory CME and unified CME/CPD-system. A trend among younger radiologists towards ELM was observed. Only 20% of employers fully endorsed CME/CPD. In 2020, LEE attendance dropped significantly (95.5-33%), with a simultaneous surge (33-58%) in time spent on ELM. Post-pandemic, the majority (52%) of LEE attendees participated in 1-5 events, whereas the majority (38%) of attendees of live-streamed events participated in 6-20 meetings. Content remains a priority of respondents in all formats: 79% for online, 75% for on-site, and 74% for on-demand. While the assessed quality of LEE remained at the same level (no change (36%) or good/very good (48%)), a considerably higher percentage of respondents noticed the quality of live-streamed events was good/very good (83%). CONCLUSION: The majority of European radiologists support mandatory CME and a unified CME/CPD system. Despite the post-pandemic resurgence in LEE, ELM and hybrid events are predicted to gain further prominence. CRITICAL RELEVANCE STATEMENT: The CME/CPD system dynamically adapts to evolving professional, technical, and environmental circumstances, with human interaction gaining heightened significance post-COVID-19. KEY POINTS: Professionals expressed a desire to return to on-site participation, highlighting its desirability for social interaction. Electronic learning materials are poised for continued growth, particularly among younger generations. Professionals expressed a desire towards a unified CME/CPD system in Europe.
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Advancements in high-temperature thermoelectric materials have been substantial, yet identifying promising near-room-temperature candidates for efficient power generation from low-grade waste heat or thermoelectric cooling applications has become critical but proven exceedingly challenging. Bismuth oxyselenide (Bi2O2Se) emerges as an ideal candidate for near-room-temperature energy harvesting due to its low thermal conductivity, high carrier mobility and remarkable air-stability. In this study, the thermoelectric properties of few-layer Bi2O2Se over a wide temperature range (20 - 380 K) are investigated, where a charge transport mechanism transitioning from polar optical phonon (POP) to piezoelectric scattering at 140 K is observed. Moreover, the Seebeck coefficient (S) increases with temperature up to 280 K then stabilizes at ~-200 µV/K through 380 K. Bi2O2Se demonstrates high mobility (450 cm2V-1s-1) within the optimum power factor (PF) window, despite its T^(-1.25) dependence. The high mobility compensates the minor reduction in carrier density n2D hence contributes to maintain a robust electrical conductivity ~3x104 S/m. This results in a remarkable PF of 860 µW m-1K-2 at 280 K without the necessity for gating (Vg = 0 V), reflecting the innate performance of the as-grown material. These results underscore the considerable promise of Bi2O2Se for room temperature thermoelectric applications.
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Liver cancer is one of the aggressive primary tumors as evident by high rate of incidence and mortality. Conventional treatments (e.g. chemotherapy) suffer from various drawbacks including wide drug distribution, low localized drug concentration, and severe off-site toxicity. Therefore, they cannot satisfy the mounting need for safe and efficient cancer therapeutics, and alternative novel strategies are needed. Nano-based drug delivery systems (NDDSs) are among these novel approaches that can improve the overall therapeutic outcomes. NDDSs are designed to encapsulate drug molecules and target them specifically to liver cancer. Thus, NDDSs can selectively deliver therapeutic agents to the tumor cells and avoid distribution to off-target sites which should improve the safety profile of the active agents. Nonetheless, NDDSs should be well designed, in terms of the preparing materials, nanocarriers structure, and the targeting strategy, in order to accomplish these objectives. This review discusses the latest advances of NDDSs for cancer therapy with emphasis on the aforementioned essential design components. The review also entails the challenges associated with the clinical translation of NDDSs, and the future perspectives towards next-generation NDDSs.
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The intrinsic low-symmetry crystal structures or external geometries of low-dimensional materials are crucial for polarization-sensitive photodetection. However, these inherently anisotropic materials are limited in variety, and their anisotropy is confined to specific crystal directions. Transforming 2D semiconductors, such as WSe2, from isotropic 2D nanosheets into anisotropic 1D nanoscrolls expands their application in polarization photodetection. Despite this considerable potential, research on polarization photodetection based on nanoscrolls remains scarce. Here, the uniform crystalline orientation of WSe2 nanoscrolls is achieved conveniently and efficiently by applying ethanol droplets to vapor deposition-grown bilayer WSe2 nanosheets. Angle-resolved polarized Raman spectroscopy of WSe2 nanoscrolls demonstrates vibrational anisotropy. Photodetectors based on these nanoscrolls show competitive overall performance with a broadband detection range from 405 to 808 nm, a competitive on/off ratio of ≈900, a high detectivity of 3.4 × 108 Jones, and a fast response speed of ≈30 ms. Additionally, WSe2 nanoscroll-based photodetectors exhibit strong polarization-sensitive detection with a maximum dichroic ratio of 1.5. More interestingly, due to high photosensitivity, the WSe2 nanoscroll detectors can easily record sequential puppy images. This work reveals the potential of WSe2 nanoscrolls as excellent polarization-sensitive photodetectors and provides new insights into the development of high-performance optoelectronic devices.