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关键词： 3D-printed overdentures   Milled overdentures   Ball attachment   Denture adaptation   Peri-implant health  

摘要： This study aimed to compare denture base adaptation and peri-implant soft tissue health between CAD/CAM milled and 3D-printed mandibular implant-assisted overdentures. Twenty-four completely edentulous patients were enrolled and randomly allocated to two groups. After two dropouts, twenty-two patients completed the trial (11 per group). All patients received two implants in the mandibular canine region with ball attachments. The intervention group received a CAD/CAM milled mandibular overdenture, while the control group received a 3D-printed mandibular overdenture;both groups received a conventional maxillary complete denture. Peri-implant soft tissue health was assessed using clinical parameters, including Gingival Index (GI), Plaque Index (PI), Bleeding Index (BI), and Probing depth (PD) at insertion (T0), six months (T6), and one year (T12) after denture insertion. The adaptation of the denture base for both groups was assessed by digital surface matching software (Geomagic). Regarding peri-implant soft tissue health, clinical parameters increased significantly with time for both groups, and there was no significant difference in all parameters between the two groups at all observational times. The whole surface adaptation between the two groups was significantly different, with Group I showing significantly higher adaptation than Group II. Within the limitations of this study, CAD/CAM milled implant-assisted mandibular overdentures demonstrated superior denture base adaptation compared to their 3D-printed counterparts. This finding underscores the precision achievable with subtractive manufacturing for definitive prostheses. Regarding the peri-implant tissues, both groups maintained comparable and stable levels of plaque control and gingival health throughout the observation *** Trial Registration Number: No. NCT06166446.

关键词： clinical competence   computer-aid design   dental education   dental restiration   MESH terms   students   tooth preparation  

摘要： Aim: This study aimed to evaluate the effectiveness of a standardized, evidence-based protocol for teaching posterior tooth preparation for CAD/CAM indirect restorations to undergraduate dental students, using prepCheck PRO 5.0 exclusively as an objective assessment *** and Methods Thirty-three fourth- and fifth-year students performed a total of 40 clinical posterior preparations for indirect adhesive restorations in actual patients. Twenty students followed a structured CAD/CAM preparation protocol, while thirteen used conventional techniques. All preparations were digitally scanned and objectively evaluated with prepCheck PRO 5.0 for undercuts, margin quality, surface smoothness, and occlusal clearance. Students in the experimental group also completed a perception *** The standardized protocol resulted in significantly higher rates of acceptable margin quality (85% vs. 40%, p = 0.006) and surface smoothness (80% vs. 35%, p = 0.008). The odds of achieving optimal margins and surfaces were more than 20-fold and 10-fold higher, respectively. Undercut presence and occlusal clearance showed no significant differences. Students reported increased confidence and strong support for integrating the protocol into preclinical *** A structured preparation protocol was associated with improved preparation quality and enhanced student confidence, supporting its integration into modern prosthodontic curricula.

关键词： Dental materials   Three-Dimensional printing   Ceramics   Biocompatibility   LC-MS/MS  

摘要： Objective This study aimed to compare surface properties, degree of conversion (DC), short-term eluate levels, and biocom-patibility between high-filler three-dimensional (3D) printed dental resins, low-filler 3D printed dental resins, and milled ceramic materials.
Materials and methods Two commercial high-filler 3D printed resins (containing zirconia and silica), one commercial low-filler 3D printed resin, one hybrid milled ceramic, and one zirconia milled ceramic were tested. The surface properties evalu-ated were degree of conversion (DC) (n = 10), contact angle and surface free energy (SFE) (n = 10), surface roughness using contact-type profiler (n = 10) and Atomic Force Microscopy (AFM, n = 1) and surface morphology using Scanning Electronic Microscopy (SEM, n = 1). Biocompatibility was assessed by measuring the viability (n = 10), proliferation (n = 3), and migra-tion (n = 6) of human gingival fibroblasts after exposure to material eluates. Eluates were analyzed subjectively using liquid chromatography-tandem mass spectrometry (n = 1). Data were analyzed statistically using one-way ANOVA with Tukey's HSD test (alpha = 0.05).
Results High-filler resins showed significantly higher DC than the low-filler resin (p < 0.05). Postcuring increased DC in the low-filler resin but not in high-filler resins. High-filler resins and the hybrid ceramic exhibited higher surface energy and lower contact angles than zirconia and the low-filler resin, while surface roughness was highest in the hybrid ceramic and lowest in the low-filler resin (p < 0.05). Eluates had no effect on viability or proliferation but significantly reduced fibroblast migration for the high-filler resins and hybrid ceramic (p < 0.05).
Conclusions High-filler 3D printed resins demonstrated higher DC and surface energy but released more residual monomers than the low-filler resin and ceramics. While eluates did not impair cell viability or proliferation, they reduced fibroblast migration,

关键词： Orthodontic retainers   Lingual retention   Computer-aided design   Transfer accuracy   Nickel-titanium   Cobalt-chromium  

摘要： Objectives This study aimed to evaluate the immediate three-dimensional (3D) transfer accuracy of three virtually designed CAD/CAM lingual retainers fabricated from nickel-titanium (NiTi), titanium grade 5 (Ti5), and cobalt-chromium (CoCr). The investigation represents the baseline (T = 0) phase of a registered randomized clinical trial (DRKS00028974). Materials and methods Sixty patients (32 females, 28 males;mean age 19.2 +/- 6.9 years) were randomly allocated to receive one of the three CAD/CAM retainers. Immediately after bonding (T0-T1), intraoral scans were superimposed with the digital design to determine deviations at predefined interproximal contact points. Non-parametric Kruskal-Wallis tests with Dunn's post-hoc comparisons were applied (p <= 0.05). Results All 60 patients completed the baseline assessment. Transfer deviations were lowest in the NiTi group (0.17 mm, IQR 0.16-0.21), followed by Ti5 (0.37 mm, IQR 0.32-0.41) and CoCr (0.35 mm, IQR 0.30-0.40). NiTi showed significantly higher transfer accuracy compared with Ti5 (p < 0.001) and CoCr (p < 0.001). No significant difference was observed between Ti5 and CoCr (p > 0.999). No adverse events occurred. Conclusions Laser-cut NiTi CAD/CAM retainers demonstrated significantly higher immediate transfer precision than milled Ti5 and CoCr retainers. These findings represent the baseline phase of the ongoing randomized clinical trial;subsequent analyses will determine whether such accuracy differences translate into clinically relevant stability outcomes. Clinical relevance Accurate passive fit of CAD/CAM retainers is essential to prevent unwanted forces on teeth. Understanding material-dependent transfer deviations may improve digital bonding workflows and guide material selection in clinical orthodontics.

关键词： air permeability   woven fabric   filament assembly model   CAD   CFD   textile simulation  

摘要： This study presents the development of a three-dimensional (3D) filament assembly model for predicting the air permeability of woven fabrics composed of spun yarns. To address the limitations of conventional single-line yarn models, the proposed framework incorporates fiber-level geometric representations using non-uniform rational B-splines (NURBS) and simulates multiple weave patterns-including plain, basket, twill, and rib-under various set density configurations. Each yarn was modeled with accurate filament distribution and cross-sectional layering, enabling the construction of realistic unit-cell-based CAD geometries. Computational fluid dynamics (CFD) simulations were performed using the k-epsilon turbulence model in SolidWorks Flow Simulation and validated against experimental measurements conducted under ISO 9237:1995 conditions. The filament assembly model achieved high predictive accuracy, exhibiting a lower of percentage prediction errors than the single-line yarn path model, thereby more effectively capturing airflow behavior through inter-yarn and intra-yarn pores. These findings highlight the capability of integrated CAD/CFD methodologies for virtual prototyping of breathable textiles and provide a robust foundation for high-precision performance prediction in functional and technical fabric design.

关键词： climate model   critical bulk Richardson number   PBL height   PBL parameterization   precipitation  

摘要： In this study, two planetary boundary layer (PBL) schemes in the National Center for Atmospheric Research Community Atmosphere Model version 5 (NCAR-CAM5) have been evaluated over India and its adjacent regions during winter (DJF), pre-monsoon (MAM), monsoon (JJA), and post-monsoon (SON) seasons. Most of the PBL schemes are designed to compute vertical mixing considering two sources of turbulence, namely buoyancy and shear. Here, the two PBL schemes, namely the HB (Holtslag and Boville, 1993) and UW (University of Washington scheme;Bretherton and Park, 2009) schemes, are considered for the evaluation. One is based on the non-local approach, while the other employs a 1st-order local TKE (turbulent kinetic energy) closure approach, respectively. The evaluation reveals that the UW PBL is preferable for precipitation throughout the winter and monsoon seasons. In contrast, HB PBL demonstrates better performance during the pre-monsoon and post-monsoon seasons over the whole study domain (20S-40N, 40E-140E). For 2-m temperature, UW PBL is beneficial in NCAR-CAM5 during all four seasons. In the case of surface and upper air wind patterns, both schemes are comparable with respect to observed monsoon flow and location of jets, with a slight difference in magnitude. Notably, over the Indian land and associated different climatic zones, significant differences have been observed between simulated variables utilising the two schemes. The performance is strongly dependent on the considered season and region, and a scheme should judiciously be chosen for the simulation. Furthermore, the sensitivity of the HB PBL scheme to the critical bulk Richardson number (Ri(cr)) suggests that the simulated variables are highly sensitive to the utilised value of Ri(cr). The mean planetary boundary layer height and total precipitation averaged over the whole domain increase linearly with increasing Ri(cr) during all four seasons. The surface sensible (latent) heat flux decreases (increases) as R

关键词： adhesion-clutch   cell motility   glioblastoma   haptotaxis   L1CAM  

摘要： L1CAM is a member of the immunoglobulin superfamily involved in cell adhesion, migration, and neural development. While several studies have shown an association between L1CAM and glioblastoma (GBM) cell motility, its mechanobiological function in patient-derived primary cultured GBM cells remains insufficiently understood. This study focuses on L1CAM-dependent motility mechanisms in patient-derived GBM cells at the single-cell level. Patient-derived GBM cells were established from GBM tissues using the neurosphere method. L1CAM expression was evaluated by qPCR, western blotting, flow cytometry, and immunocytochemistry. Cell motility was assessed by single-cell tracking. Functional assays included forced expression and antibody-mediated inhibition of L1CAM. Adhesion-clutch behavior and retrograde F-actin flow were analyzed. For in vivo assessment, doxycycline-inducible L1CAM-overexpressing GBM cells were transplanted into mouse brains. L1CAM-high GBM cells showed increased motility on laminin compared to L1CAM-low cells. Anti-L1CAM antibody suppressed migration of L1CAM-high GBM cells, whereas ectopic expression enhanced migration in L1CAM-low GBM cells. L1CAM-positive GBM cells preferentially migrated on laminin rather than fibronectin, while L1CAM-low cells showed no such difference, indicating L1CAM-dependent haptotaxis. Forced L1CAM expression reduced retrograde actin flow velocity and promoted adhesion-clutch formation. In vivo, GBM cells with L1CAM overexpression displayed greater infiltrative capacity 12 weeks posttransplantation. L1CAM expression on GBM cells' surface regulates cell motility through adhesion-clutch mechanisms and substrate sensing. These mechanobiological features suggest that targeting L1CAM may serve as a promising strategy to suppress GBM cells infiltration and improve GBM treatment outcomes.

关键词： Angiogenesis   Bio-imaging   Chick embryo chorioallantoic membrane (CAM) model   Sarcoma   Tumor cell-conditioned medium (TCM)   VEGFA  

摘要： We developed a sensitive bioimaging system for sarcoma by creating a cell line that stably expresses both Katushka2S fluorophore and NanoLuc luciferase, enabling robust dual tracking of tumor growth and metastasis in the chick chorioallantoic membrane (CAM) model. NanoLuc luciferase was notably more effective than Katushka2S for identifying tumor cell metastases in embryo tissues. Pretreating CAM with tumor cell-conditioned medium (TCM) significantly increased neovascularization, Ki67 expression, tumor volumes, and metastasis of the most difficult-to-establish low-tumorigenic and low-metastatic U2OS cells, indicating that tumor cell secretome actively alter the CAM vascular environment to aid tumor progression. The bead-based multiplex profiling of the TCM demonstrated a notable increase in pro-angiogenic factors. Neutralizing VEGFA, the most abundant factor in the TCM, effectively counteracted vascular and pro-metastatic effects of TCM. In contrast, elevating VEGFA levels brought back the pro-tumorigenic effects of TCM. This study reveals the importance of tumor cell secretomes in creating the vascular niche in CAM and points to VEGFA as a target to prevent secretome-induced angiogenesis and sarcoma development. Furthermore, our optimized CAM model permits continuous tumor growth and metastasis monitoring in embryonic development, providing a reliable platform for prognostic studies of sarcoma treatments in ongoing anti-angiogenic and multikinase inhibitors trials.

关键词： 3DGS   novel view synthesis   scene reconstruction   dash cam video  

摘要： Recent advancements in 3D Gaussian Splatting (3DGS) have made significant improvements in real-time novel view synthesis and 3D reconstruction. 3DGS has seen significant development in driving scenarios, but existing methods are mainly designed for videos captured by autonomous vehicles. It is not suitable for the complexity and dynamic lighting challenges present in dash cam videos. Despite the progress made by previous work in dealing with reflections and occlusions, the distribution of 3D Gaussian points remains inaccurate due to the inherent complexity of dash cam scenes, causing geometric distortions in the rendered output. Additionally, uncontrolled dynamic illumination exacerbates Gaussian point density anomalies and local geometric distortions. These challenges significantly hinder the development of scene reconstruction techniques based on dash cam videos. To address these challenges, we present RDC-GS, an innovative method featuring a point correction mechanism to eliminate distribution errors of Gaussian points during training, and a brightness-aware illumination technique to enhance detailed representation under dynamic lighting conditions. This approach yields more robust scene reconstruction. Experiments conducted on real dash cam videos demonstrate that our method achieves a 1.5-dB PSNR improvement over current state-of-the-art techniques. Comprehensive experiments validate the efficacy of our approach across challenging scenarios.

关键词： architectural drawings   CAD   deep learning  

摘要： A large number of architectural drawings have historically existed in paper form or as non-editable raster images, which makes them difficult to directly support information reuse and digital management, while manual CAD reconstruction is time-consuming and inefficient. This paper proposes a hybrid deep learning and rule-based method for architectural drawing vectorization and CAD reconstruction, which automatically converts scanned raster images into editable CAD vector files while preserving geometric structure and scale consistency. The proposed method consists of four modules: axis grid and dimension detection, text recognition and scale recovery, architectural line topology reconstruction, and CAD geometric rectification and reconstruction. The method utilizes object detection and OCR technologies to extract key semantic information from the drawings. By extracting semantic information, the method constructs a line topology structure and applies architectural drawing constraints to parameterize and normalize geometric results, thereby achieving the recognition and vectorization of raster drawings. Experimental results and engineering case studies demonstrate that the proposed method can effectively extract typical architectural elements, and generate directly editable CAD vector drawings. The method achieves favorable geometric accuracy and topological consistency in architectural drawing digitization and automatic CAD reconstruction tasks, providing a technical solution for the automatic vectorization of existing architectural drawings.