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This paper presents a prototype of a portable and modular electrical impedance tomography (EIT) system for breast tumor detection. The proposed system uses MATLAB to generate three-dimensional representations of breast tissue. The modular architecture of the system allows for flexible customization and scalability. It consists of several interconnected modules. Each module can be easily replaced or upgraded, facilitating system maintenance and future enhancements. Testing of the prototype has shown promising results in preliminary screening based on experimental studies. Agar models were used for the experimental stage of this project. The 3D representations provide clinicians with valuable information for accurate diagnosis and treatment planning. Further research and refinement of the system is warranted to validate its performance in future clinical trials.

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The ductus arteriosus aneurysm (DAA) is considered a rare anatomical alteration that consists of a dilation of this vascular structure. It has been reported that the DAA can resolve in the immediate postnatal stage and do not generate any consequences for the neonate. However, have been described some cases in which the DAA is complicated due to thromboembolic events, rupture of the lesion, respiratory symptoms, and even death. We present a case report of aneurysm of the ductus arteriosus diagnosed at 24 weeks of gestation with detailed imaging study. Also, we highlight the importance of the use of fundamental tools in the diagnosis: 3D ultrasound, multiplanar reconstruction, spatio-temporal image correlation (STIC), and omniview.

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In this work, acrylonitrile butadiene styrene (ABS) copolymer from electronic waste (e-waste) was used to produce filaments for application in 3D printing. Recycled ABS (rABS) from e-waste was blended with virgin ABS (vABS) in different concentrations. By differential scanning calorimetry, it was observed that the values of the glass transition temperatures for vABS/rABS blends ranged between the values of vABS and rABS. Torque rheometry analysis showed that the processability of vABS was not compromised with the addition of rABS. Rheological measurements showed that the viscosity of vABS was higher than that of rABS at low frequencies and indicated that vABS and rABS are immiscible. Impact strength (IS) tests of the 3D printed samples showed an increase in the IS with an increase in the rABS content up to 50 wt%. Blending vABS with rABS from e-waste is promising and proved to be feasible, making it possible to recycle a considerable amount of plastics from e-waste and, thus, contributing to the preservation of the environment.

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Each collective trauma holds its own particularities and forms of horror. When the violence is exerted by the government responsible for the care of the population it is termed state terrorism. The traumatic experience and its subsequent negation create a profound dissociation between two narratives: the explicit, which conceals the true facts, and the implicit, which remains unconscious and unbridgeable. In the gap between the two, life becomes suspended. From a Jungian perspective, this can be understood as the interruption of the process of translation and integration (terms that I will explore in some depth) from implicit sensory phenomena to an explicit representational narrative. This profoundly affects the development of the ego-self axis. In turn, it creates a special challenge for analytic technique that calls for new ways of listening to, and meeting the patient in, that non-verbal, unrepresented territory. Drawing upon clinical material, an embodied perspective of Jungian clinical work is offered to show how the inclusion of the body of patient and analyst enables access to the non-represented, though implicitly encoded, traumatic affective memories stored in the somatic unconscious.

Chaque traumatisme collectif a ses particularités et ses formes d'horreur. Lorsque la violence est exercée par le gouvernement responsable de la prise en charge de la population, on parle de terrorisme d'État. L'expérience traumatique et sa négation ultérieure créent une dissociation profonde entre deux récits : l'explicite, qui dissimule les faits réels, et l'implicite, qui reste inconscient et insurmontable. Dans l'écart entre les deux, la vie est suspendue. D'un point de vue jungien, cela peut être compris comme l'interruption du processus de «traduction et d'intégration¼ (termes que j'explorerai plus en profondeur) des phénomènes sensoriels implicites à un récit représentationnel explicite. Cela affecte profondément le développement de l'axe ego­soi. En conséquence, cela crée un défi particulier pour la technique analytique et invite à de nouvelles façons d'écouter et de rencontrer le patient dans ce territoire non verbal et non représenté. En s'appuyant sur le matériel clinique, une perspective incarnée du travail clinique jungien est proposée. Il s'agit de montrer qu'inclure les corps du patient et de l'analyste permet d'accéder à ce qui n'est pas représenté, par le biais de mémoires affectives traumatiques implicitement encodées et stockées dans l'inconscient somatique.

Cada trauma colectivo tiene sus propias particularidades y formas del horror. Cuando la violencia es ejercida por el gobierno responsable del cuidado de la población se denomina Terrorismo de Estado. La experiencia traumática y su posterior negación crean una profunda disociación entre dos narrativas: la explícita, que oculta los verdaderos hechos, y la implícita, que permanece inconsciente e inabordable. En la brecha entre ambas, la vida queda suspendida. Desde una perspectiva Junguiana, dicha suspensión puede entenderse como la interrupción en el proceso de "traslación e integración" (términos que exploraré con cierta profundidad) de los fenómenos sensoriales implícitos en una narrativa representacional explícita, afectando profundamente el desarrollo del eje ego­self. A su vez, crea un desafío especial para la técnica analítica que exige nuevas formas de escuchar y encontrarse con el paciente en ese territorio no­verbal y no­representado. A partir de material clínico, se ofrece una perspectiva somática del trabajo clínico Junguiano para mostrar cómo la inclusión del cuerpo de paciente y analista posibilita el acceso a estados no­representados, a través de memorias afectivas traumáticas codificadas implícitamente y almacenadas en el inconsciente somático.

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This paper proposes a low-cost electronic system for estimating ground reaction forces (GRF) during human gait. The device consists of one master node and two slave nodes. The master node sends instructions to slave nodes that sample and store data from two force insoles located at the participant's feet. These insoles are equipped with 14 piezo-resistive FlexiForce A301 sensors (FSR). The slave nodes are attached to the ankles and feet of each participant. Subsequently, the start command is transmitted through the master node, which is connected to the USB port of a personal computer (PC). Once the walking session is completed, the information obtained by the slave nodes can be downloaded by accessing the access point generated by these devices through Wi-Fi communication. The GRF estimation system was validated with force platforms (BTS Bioengineering P6000, Italy), giving on average a fit measure equal to 68 . 71 % ± 4 . 80 % in dynamic situations. Future versions of this device are expected to increase this fit by using machine learning models.

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Monocular Simultaneous Localization and Mapping (SLAM), Visual Odometry (VO), and Structure from Motion (SFM) are techniques that have emerged recently to address the problem of reconstructing objects or environments using monocular cameras. Monocular pure visual techniques have become attractive solutions for 3D reconstruction tasks due to their affordability, lightweight, easy deployment, good outdoor performance, and availability in most handheld devices without requiring additional input devices. In this work, we comprehensively overview the SLAM, VO, and SFM solutions for the 3D reconstruction problem that uses a monocular RGB camera as the only source of information to gather basic knowledge of this ill-posed problem and classify the existing techniques following a taxonomy. To achieve this goal, we extended the existing taxonomy to cover all the current classifications in the literature, comprising classic, machine learning, direct, indirect, dense, and sparse methods. We performed a detailed overview of 42 methods, considering 18 classic and 24 machine learning methods according to the ten categories defined in our extended taxonomy, comprehensively systematizing their algorithms and providing their basic formulations. Relevant information about each algorithm was summarized in nine criteria for classic methods and eleven criteria for machine learning methods to provide the reader with decision components to implement, select or design a 3D reconstruction system. Finally, an analysis of the temporal evolution of each category was performed, which determined that the classical-sparse-indirect and classical-dense-indirect categories have been the most accepted solutions to the monocular 3D reconstruction problem over the last 18 years.

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PURPOSE: The present study evaluated the mechanical, surface, and optical properties of 3D-printed resins for removable prostheses reinforced by the addition of aramid fibers. MATERIALS AND METHODS: According to ISO 20795-1:2013 standards, specimens were printed using a digital light processing 3D printer and divided into two groups (n = 06/group): 3D-printed resin for denture base as the control group, and a group with the same 3D-printed resin in addition of 5% aramid fibers as the experimental group. Red aramid fibers were chosen for aesthetic characterization. The specimens were evaluated for their mechanical properties, such as elastic modulus (GPa), flexural strength (MPa), and superficial properties by their surface microhardness (KHN), surface roughness (µm), and surface free energy (mJ/m2). Optical properties were evaluated by the color difference (∆E00) between groups. The statistical test chosen after the exploratory analysis of the data was One-way ANOVA followed by Tukey's HSD (α = 0.05). RESULTS: The results showed statistical differences in elastic modulus (p < 0.0001), flexural strength (p < 0.0001), surface free energy polar variable (p = 0.0322), total surface free energy (p = 0.0344), with higher values for the experimental. Surface hardness and surface roughness showed no statistical difference (p ≥ 0.05). The color difference (∆E00) obtained through the CIEDE2000 calculus was below the perceptibility threshold (≤1.1). CONCLUSION: Adding aramid fibers to 3D-printed resin for denture bases resulted in better mechanical properties, without major alterations in surface properties. In addition, it is an easy-to-apply choice for mechanical reinforcement and aesthetic characterization, with the expression of small blood vessels in the 3D-printed resin for removable denture bases.

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BACKGROUND/OBJECTIVES: The use of different models for the fabrication of custom-fit mouthguards (MTGs) can affect their final thickness, adaptation, and shock-absorption properties. This study aimed to evaluate the adaptation, thickness, and shock absorption of ethylene-vinyl acetate (EVA) thermoplastic MTGs produced using conventional plaster or three-dimensional (3D) printed models. MATERIALS AND METHODS: A typical model with simulated soft gum tissue was used as the reference model to produce MTGs with the following two different protocols: plast-MTG using a conventional impression and plaster model (n = 10) and 3DPr-MTG using a digital scanning and 3D printed model (n = 10). A custom-fit MTG was fabricated using EVA sheets (Bioart) plasticized over different models. The MTG thickness (mm), internal adaptation (mm) to the typodontic model, and voids in the area (mm2) between the two EVA layers were measured using cone-beam computed tomography images and Mimics software (Materialize). The shock absorption of the MTG was measured using a strain-gauge test with a pendulum impact at 30° with a steel ball over the typodont model with and without MTGs. Data were analyzed using one-way analysis of variance with repeated measurements, followed by Tukey's post hoc tests. RESULTS: The 3DPr-MTG showed better adaptation than that of the Plast-MTG at the incisal/occlusal and lingual tooth surfaces (p < 0.001). The 3DPr-MTG showed a thickness similar to that of the Plast-MTG, irrespective of the measured location. MTGs produced using both model types significantly reduced the strain values during horizontal impact (3DPr-MTG 86.2% and Plast-MTG 87.0%) compared with the control group without MTG (p < 0.001). CONCLUSION: The MTGs showed the required standards regarding thickness, adaptation, and biomechanical performance, suggesting that the number and volume of voids had no significant impact on their functionality. Three-dimensional printed models are a viable alternative for MTG production, providing better adaptation than the Plast-MTG at the incisal/occlusal and lingual tooth surfaces and similar performance as the MTG produced with the conventional protocol.

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OBJECTIVE: proximal enamel caries lesions (PEC) are believed to initiate and progress to cavitation below the proximal contact area (PCA), but no evidence exists on the location of initial carious cavitation on the proximal surface with functional PCA. This study aimed to test the association of anatomical areas of the proximal surface with the severity of PEC and the frequency of cavitation in PEC in primary molars DESIGN: laboratory, observational, transversal study. Exfoliated primary molars (n = 33) with functional PCA (biofilm-free PCA surrounded by biofilm) had their proximal surfaces (one/tooth) divided anatomically into up to nine areas: 3 areas based on the occlusal/cervical PCA boundaries (areas I, II, and III; occluso-cervically) and 3 areas based on the bucco/lingual PCA boundaries (A, B, and C), with area IIB representing the PCA and area IIIB as the sub-PCA (below the PCA). PEC (ICDAS scores 1 and 2-3) and cavitation in PEC were quantified in all areas using stereomicroscopy and microCT. PEC volume was quantified in areas IIB and IIIB under microCT RESULTS: PEC severity increased occluso-cervically. PCA and sub-PCA presented different PEC severities (higher in sub-PCA) and similar PCE volumes, but the odds of carious cavitation were much higher (Odds ratio = 197.4; 95 % CI: 8.7/4480.7) in the PCA than in the sub-PCA (no cavitation). CONCLUSION: PCA presented lower PEC severity and similar PEC volume compared to sub-PCA, but PCA concentrated all cavitations in PEC, supporting a new model for the pathogenesis of PEC.

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BACKGROUND: Accurate diagnosis and treatment of complex cardiac tumors poses challenges, particularly when surgical resection is considered. 3D reconstruction and printing appear as a novel approach to allow heart teams for optimal surgical and post operative care. METHODS: We report two patients with uncommon masses including a cardiac angiosarcoma (CAS) and a IgG4-related disease (IgG4-RD) with exclusive cardiac involvement. In both cases, three-dimensional (3D) reconstruction and 3D-printed models were utilized to aid the surgical team achieve optimal pre-operative planning. Both patients underwent ECG-gated cardiac computed tomography angiography (CCTA) imaging and, due to the complex anatomy of the masses, their large dimensions, proximity to vital cardiac and vascular structures, and unclear etiology, computational and 3D-printed models were created for surgical planning. An exploratory literature review of studies using 3D-printed models in surgical planning was performed. RESULTS: In case 1 (CAS), due to the size and extension of the mass to the right ventricular free wall, surgical intervention was not considered curative and, during thoracotomy, an open biopsy confirmed the imaging suspicion of CAS which guided the initiation of optimal medical treatment with chemotherapy and, after clear tumor retraction, the patient underwent a second surgical intervention, and during the 18 months of follow-up showed no signs of recurrence. In Case 2 (IgG4-RD), the patient underwent uncomplicated total surgical resection; this allowed directed treatment and, at 12 months follow-up, there are no signs of recurrence. Computational and 3D-printed models were used to plan the surgery and to confirm the findings. Limited studies have explored the use of 3D printing in the surgical planning of tumors. CONCLUSIONS: We present two patients with uncommon cardiac tumors, highlighting the significant value of 3D models in the anatomical characterization and assessment of their extension. These models may be essential in surgical planning for complex cardiovascular cases and could provide more information than conventional imaging modalities. Further studies are needed to demonstrate the impact of 3D technologies in studying cardiac tumors.

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Calcium phosphate (CaP) scaffolds doping with therapeutic ions are one of the focuses of recent bone tissue engineering research. Among the therapeutic ions, strontium stands out for its role in bone remodeling. This work reports a simple method to produce Sr-doped 3D-printed CaP scaffolds, using Sr-doping to induce partial phase transformation from ß-tricalcium phosphate (ß-TCP) to hydroxyapatite (HA), resulting in a doped biphasic calcium phosphate (BCP) scaffold. Strontium carbonate (SrCO3) was incorporated in the formulation of the 3D-printing ink, studying ß-TCP:SrO mass ratios of 100:0, 95:5, and 90:10 (named as ß-TCP, ß-TCP/5-Sr, and ß-TCP/10-Sr, respectively). Adding SrCO3 in the 3D-printing ink led to a slight increase in viscosity but did not affect its printability, resulting in scaffolds with a high printing fidelity compared to the computational design. Interestingly, Sr was incorporated into the lattice structure of the scaffolds, forming hydroxyapatite (HA). No residual SrO or SrCO3 were observed in the XRD patterns of any composition, and HA was the majority phase of the ß-TCP/10-Sr scaffolds. The addition of Sr increased the compression strength of the scaffolds, with both ß-TCP/5-Sr and ß-TCP/10-Sr performing better than the ß-TCP. Overall, ß-TCP/5-Sr presented higher mineralized nodules and mechanical strength, while ß-TCP scaffolds presented superior cell viability. The incorporation of SrCO3 in the ink formulation is a viable method to obtain Sr-BCP scaffolds. Thus, this approach could be explored with other CaP scaffolds aiming to optimize their performance and the addition of alternative therapeutic ions.

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Several studies have demonstrated that low-dimensional structures (e.g., two-dimensional (2D)) associated with three-dimensional (3D) perovskite films enhance the efficiency and stability of perovskite solar cells. Here, we aim to track the formation sites of the 2D phase on top of the 3D perovskite and to establish correlations between molecular stiffness and steric hindrance of the organic cations and their influence on the formation and crystallization of 2D/3D. Using cathodoluminescence combined with a scanning electron microscopy technique, we verified that the formation of the 2D phase occurs preferentially on the grain boundaries of the 3D perovskite. This helps explain some passivation mechanisms conferred by the 2D phase on 3D perovskite films. Furthermore, by employing in situ grazing-incidence wide-angle X-ray scattering, we monitored the formation and crystallization of the 2D/3D perovskite using three cations with varying molecular stiffness. In this series of molecules, the formation and crystallization of the 2D phase are found to be dependent on both steric hindrance around the ammonium group and molecular stiffness. Finally, we employed a 2D/3D perovskite heterointerface in a solar cell. The presence of the 2D phase, particularly those formed from flexible cations, resulted in a maximum power conversion efficiency of 21.5%. This study provides insight into critical aspects related to how bulky organic cations' stiffness and steric hindrance influence the formation, crystallization, and distribution of 2D perovskite phases.

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The development of a tailored filament is reported composed of reduced graphene oxide (rGO) and carbon black (CB) in a polylactic acid (PLA) matrix and its use in the production of electrochemical sensors. The electrodes containing rGO showed superior performance when compared with  those prepared in the absence of this material. Physicochemical and electrochemical characterizations of the electrodes showed the successful incorporation of both rGO and CB and an improved conductivity in the presence of rGO (lower resistance to charge transfer). As a proof-of-concept, the developed electrodes were applied to the detection of the forensic analytes TNT and cocaine. The electrodes containing rGO presented a superior analytical performance for both TNT and cocaine detection, showing the lower limit of detection values (0.22 and 2.1 µmol L-1, respectively) in comparison with pure CB-PLA electrodes (0.93 and 11.3 µmol L-1, respectively). Besides, better-defined redox peaks were observed, especially for TNT, as well as increased sensitivity for both molecules.

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This study evaluated the efficacy of synthetic bone blocks, composed of hydroxyapatite (HA) or ß-tricalcium phosphate (B-TCP), which were produced by additive manufacturing and used for the repair of critical size bone defects (CSDs) in rat calvaria. Sixty rats were divided into five groups (n = 12): blood clot (CONTROL), 3D-printed HA (HA), 3D-printed ß-TCP (B-TCP), 3D-printed HA + autologous micrograft (HA+RIG), and 3D-printed ß-TCP + autologous micrograft (B-TCP+RIG). CSDs were surgically created in the parietal bone and treated with the respective biomaterials. The animals were euthanized at 30 and 60 days postsurgery for microcomputed tomography (micro-CT) histomorphometric, and immunohistochemical analysis to assess new bone formation. Micro-CT analysis showed that both biomaterials were incorporated into the animals' calvaria. The HA+RIG group, especially at 60 days, exhibited a significant increase in bone formation compared with the control. The use of 3D-printed bioceramics resulted in thinner trabeculae but a higher number of trabeculae compared with the control. Histomorphometric analysis showed bone islands in close contact with the B-TCP and HA blocks at 30 days. The HA blocks (HA and HA+RIG groups) showed statistically higher new bone formation values with further improvement when autologous micrografts were included. Immunohistochemical analysis showed the expression of bone repair proteins. At 30 days, the HA+RIG group had moderate Osteopontin (OPN) staining, indicating that the repair process had started, whereas other groups showed no staining. At 60 days, the HA+RIG group showed slight staining, similar to that of the control. Osteocalcin (OCN) staining, indicating osteoblastic activity, showed moderate expression in the HA and HA+RIG groups at 30 days, with slight expression in the B-TCP and B-TCP+RIG groups. The combination of HA blocks with autologous micrografts significantly enhanced bone repair, suggesting that the presence of progenitor cells and growth factors in the micrografts contributed to the improved outcomes. It was concluded that 3D-printed bone substitute blocks, associated with autologous micrografts, are highly effective in promoting bone repair in CSDs in rat calvaria.

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PURPOSE: To evaluate the effect of cleaning solutions on surface properties of 3D-printed resins. MATERIALS AND METHODS: Seven different resin materials for denture base and teeth were used in the form of 280 half-disks. Samples were randomly assigned to two cleaning groups (FD, FreshDent; PO, Polydent), with daily 2- or 3-min immersion followed by water storage, repeated for 30 days. Samples were then cleaned in an ultrasonic bath with water and analyzed for surface roughness (Keyence, VHX-7000N) and hardness (Shimadzu, HMV-2 series). The pH of cleaning solutions was analyzed over 5-min and the surface morphology of specimens was analyzed via scanning electron microscopy (SEM). Statistical analysis used two-way ANOVA (α = 0.05). RESULTS: Surface roughness of base materials was significantly affected (p < 0.001), whereas roughness of teeth materials was not. As for hardness, there was a significant interaction between materials and cleaning solution for both, base (p < 0.001) and teeth (p < 0.001). For teeth materials, PO significantly increased Denture's (Dentca) hardness and decreased that of Rodin's (Pac Dent), while PO significantly increased Rodin's Base (Pac Dent) hardness. The hardness of Flexcera Ultra (Envision Tec), Glidewell (Glidewell), Lucitone (Dentsply Sirona), and NextDent (NextDent) teeth and base materials were not affected by the cleaning solution. Overall, the pH of FD averaged 7.3 and PO averaged 6.6. All the SEM images indicated surface irregularities after immersion in either FD or PO. CONCLUSIONS: One-month of storage and cyclic cleaning of 3D- printed resins did not affect surface roughness but had a significant impact on hardness. The cleaning solutions' effect was not homogeneous among materials.

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Molecular and cellular characterization of tumors is essential due to the complex and heterogeneous nature of cancer. In recent decades, many bioinformatic tools and experimental techniques have been developed to achieve personalized characterization of tumors. However, sample handling continues to be a major challenge as limitations such as prior treatments before sample acquisition, the amount of tissue obtained, transportation, or the inability to process fresh samples pose a hurdle for experimental strategies that require viable cell suspensions. Here, we present an optimized protocol that allows the recovery of highly viable cell suspensions from breast cancer primary tumor biopsies. Using these cell suspensions we have successfully characterized genome architecture through Hi-C. Also, we have evaluated single-cell gene expression and the tumor cellular microenvironment through single-cell RNAseq. Both technologies are key in the detailed and personalized molecular characterization of tumor samples. The protocol described here is a cost-effective alternative to obtain viable cell suspensions from biopsies simply and efficiently.

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Cortical organoids derived from human induced pluripotent stem cells (hiPSCs) represent a powerful in vitro experimental system to investigate human brain development and disease, often inaccessible to direct experimentation. However, despite steady progress in organoid technology, several limitations remain, including high cost and variability, use of hiPSCs derived from tissues harvested invasively, unexplored three-dimensional (3D) structural features and neuronal connectivity. Here, using a cost-effective and reproducible protocol as well as conventional two-dimensional (2D) immunostaining, we show that cortical organoids generated from hiPSCs obtained by reprogramming stem cells from human exfoliated deciduous teeth (SHED) recapitulate key aspects of human corticogenesis, such as polarized organization of neural progenitor zones with the presence of outer radial glial stem cells, and differentiation of superficial- and deep-layer cortical neurons and glial cells. We also show that 3D bioprinting and magnetic resonance imaging of intact cortical organoids are alternative and complementary approaches to unravel critical features of the 3D architecture of organoids. Finally, extracellular electrical recordings in whole organoids showed functional neuronal networks. Together, our findings suggest that SHED-derived cortical organoids constitute an attractive model of human neurodevelopment, and support the notion that a combination of 2D and 3D techniques to analyze organoid structure and function may help improve this promising technology.

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PURPOSE: To investigate the effects of different surface treatments and thermal cycling on the shear bond strength between 3D-printed teeth and denture bases. MATERIAL AND METHODS: For the shear bond strength (SBS) test, the specimens were the maxillary central incisors (11 × 9 × 7 mm) bonded on a cylindrical base (20 × 25 mm). The control group was heat-cured polymethylmethacrylate (PMMA) (N = 20). The printed group was divided into five subgroups (N = 20): no treatment, sandblasting with aluminum oxide (Al2O3), methyl methacrylate monomer, acetone, and adhesive with urethane dimethacrylate. Half of the samples were subjected to 2000 thermal cycling cycles, and all samples were subjected to the SBS test. The failure mode was established as adhesive, cohesive, or mixed through stereomicroscopic analysis. The surface roughness test (Sa) was performed using optical profilometry, and the rectangular specimens (14 × 14 × 2.5 mm) were divided into four groups according to the surface treatments (N = 7 per group). Paired T and Wilcoxon tests were conducted to perform comparisons within the same group. The Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner post-hoc tests were conducted to compare the groups. RESULTS: Al2O3 sandblasting in the 3D-printed groups achieved high SBS values comparable to those of the control group in the thermal cycled (p = 0.962) and non-thermal cycled samples (p = 0.319). It was the only treatment capable of modifying the surface of the 3D-printed resin, thereby increasing the roughness (p = 0.016). CONCLUSIONS: Sandblasting is recommended to increase the bond strength between the tooth and denture bases.

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Abstract The color stability of temporary restoration is crucial, especially in sensitive areas in terms of aesthetics. This research aimed to determine the effect of temporary cement on the color of temporary crowns made by conventional pressing methods (indirect) and CAM/CAD technologies using milling machines and 3D printers. This study was carried out in a laboratory, utilizing A2 color in all manufacturing methods. The color of the restorations was measured by a spectrophotometer after cementation with semi-permanent resin cement. Subsequently, color changes of the samples (ranging from 0 to 100) were calculated using the Commission International de l'Eclairage (CIE) Lab system. Data analysis was based on descriptive statistics methods and statistical tests, including one-way analysis of variance (ANOVA) and Tukey's post hoc test. According to the results of ANOVA, there was a significant difference between the three groups in terms of the 'a' and 'b' indexes (P<0.001). However, regarding the 'l' index, no significant difference was observed among the three groups (P=0.250). Also, based on Tukey's post hoc test, a significant relationship was seen between the first and second pairs in the 3D printer group, and between the first and third pairs in the milling group (P<0.001). However, no significant difference was observed in the conventional pressing group. The results showed that the 3D printing method exhibited the highest amount of color change among the three methods, while the milling method demonstrated the lowest amount of change.

Resumen La estabilidad del color de la restauración temporal es muy importante, especialmente en zonas sensibles desde el punto de vista estético. En la presente investigación, el objetivo fue determinar el efecto del cemento temporal sobre el color de coronas temporales realizadas mediante métodos de prensado convencionales (indirectos) y tecnologías CAM/CAD utilizando fresadora e impresora 3D. Este estudio se llevó a cabo en un laboratorio y se utilizó color A2 en todos los métodos de fabricación. El color de las restauraciones se midió mediante un espectrofotómetro después de cementarlas con cemento de resina provisional. Luego se calcularon los cambios de color de las muestras (de 0 a 100) utilizando el sistema CIE Lab. El análisis de los datos se basó en métodos de estadística descriptiva y pruebas estadísticas, incluido el análisis de varianza unidireccional (ANOVA) y la prueba post hoc de Tukey. Según los resultados del análisis de varianza unidireccional, hubo una diferencia significativa entre los tres grupos en términos de los índices a y b (P<0,001), pero en términos del índice l, no hubo diferencias significativas entre los tres grupos (P=0,250). Además, según la prueba post hoc de Tukey, se observó una relación significativa entre el primer y el segundo grupo de impresoras 3D y entre el primer y el tercer grupo de fresado (P<0,001). Sin embargo, no se observó ninguna diferencia significativa en el grupo de prensado convencional. Los resultados mostraron que el mayor cambio de color entre los tres métodos fue con el método de impresión 3D, y la menor cantidad fue con el método de fresado.

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SUMMARY: In this study, we aim to share the volumes of the carpal bone and the ratio of these volumes to the total volume of wrist bones from Computed Tomography (CT) images obtained from individuals of different ages and sex using 3D Slicer. Right wrist CT images of 0.625 mm slice thickness of 42 healthy individuals (21 female, 21 male) of both sexes were included in our study. Volume calculations were made by loading the images into 3D Slicer, an open-source software package. In this study, mean capitate volume was the largest in both sexes (male 3479.9±679.2; female 2207.1±272.1 mm3), while pisiform had the smallest mean volume (male 810.0±141.2; female 566.6±97.7 mm3). This order was ordered from largest to smallest as hamate, scaphoid, trapezium, lunate, triquetrum, trapezoid, and pisiform. According to this study, carpal bone volumes were larger in males than in females (p0.05). In this study, it was seen that carpal bone volume differed according to sex. However, it was observed that the bone volumes of both sexes took up the same amount in the total bone volume. This information will be very useful in sex determination, 3D anatomical material creation, implant applications and reconstructive surgery.

Nuestro objetivo fue determinar los volúmenes de los huesos del carpo y la relación entre estos volúmenes y el volumen total de estos huesos a partir de imágenes de TC obtenidas de individuos de diferentes edades y sexos utilizando 3D Slicer. En el estudio se incluyeron imágenes de TC del carpo de la mano derecha de los participantes en el estudio, con un grosor de corte de 0,625 mm, en 42 individuos sanos (21 mujeres, 21 hombres) de ambos sexos. Los cálculos de volumen se realizaron cargando las imágenes en 3D Slicer, un paquete de software de código abierto. El volumen medio del hueso capitado fue el mayor en ambos sexos (hombre 3479,9 ± 679,2; mujer 2207,1 ± 272,1 mm3), mientras que el hueso pisiforme tuvo el volumen medio más pequeño (hombre 810,0 ± 141,2; mujer 566,6 ± 97,7 mm3). De mayor a menor el volumen de los otros huesos fue: hamato, escafoides, trapecio, lunato, piramidal, trapezoide y pisiforme. Según este estudio, los volúmenes óseos del carpo eran mayores en hombres que en mujeres (p0,05). En este estudio se observó que el volumen de los huesos del carpo difería según el sexo. Sin embargo, se observó que los volúmenes óseos de ambos sexos ocuparon la misma cantidad del volumen óseo total. Esta información será de gran utilidad en la determinación del sexo, creación de material anatómico 3D, aplicaciones de implantes y cirugía reconstructiva.

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