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关键词： Removable partial dentures   CAD-CAM   Commercially pure titanium  

摘要： Purpose: Commercially pure titanium (CP-Ti) is ideal for removable partial denture (RPD) frameworks owing to its biocompatibility and corrosion resistance;however, conventional casting can introduce defects and dimensional errors. This study compared the shape accuracy, surface roughness, microstructure, and internal pores of CP-Ti RPD frameworks prepared wax: casting from a milled wax pattern;(3) Ti-milling: direct milling from a CP-Ti disc;and (4) Ti-SLM: selective laser melting. Methods: Forty frameworks were prepared for each group (N = 10). Shape accuracy was assessed using 3D data-inspection software, surface roughness was analyzed using laser microscopy, the microstructure was determined using X-ray diffraction, and internal pores were examined using micro-computed tomography. Nonparametric statistics (Kruskal-Wallis and Results: Ti-SLM achieved the highest trueness (median: 0.00 mm;IQR: 0.09 mm) and precision (median: 0.01 mm;IQR: 0.02 mm), while Ti-milling yielded the lowest surface roughness (median arithmetic mean height: 0.61 & micro;m;IQR: 0.05 & micro;m). Internal pores were absent in Ti-milling and minimal in Ti-SLM (0-1), whereas Ti-resin and Ti-wax produced 319 and 171 pores (median), respectively. Significant inter-method differences were found in shape accuracy, surface roughness, and Conclusions: The fabrication method affected the dimensional accuracy, surface conditions, crystalline features, and internal pores of the CP-Ti frameworks. Ti-milling and Ti-SLM outperformed the casting-based methods (Ti-resin and Tiwax) in terms of accuracy and defect reduction. These digital approaches may improve the reproducibility and precision of clinical fabrication of CP-Ti RPD frameworks.

关键词： CAD-CAM   Digital dentistry   Milling   All-ceramic   Glass-ceramics  

摘要： Purpose: The aim of the current systematic review was to compare the internal fit of lithium disilicate crowns, fabricated Study selection: A comprehensive literature search was conducted in PubMed, Embase, Scopus, and the Cochrane Library up to December 2025, following PRISMA guidelines and registered in the Open Science Framework. Eleven studies met the inclusion criteria (nine in vitro studies and two clinical trials), of which nine were included in the quantitative synthesis. Results: The random-effects meta-analysis demonstrated no statistically significant difference in internal fit between heat-pressed and CAD-CAM-milled crowns, although substantial heterogeneity was observed (I2=95%). Sensitivity analysis excluding five methodologically heterogeneous studies revealed a statistically significant pooled effect favoring heat-pressed crowns (MD=-18.92 mu m;95% CI: -29.77 to -8.07;P = 0.008), with markedly reduced heterogeneity (I2=19%). Subgroup analysis suggested that elastomeric impressions may be associated with better internal fit compared with digital workflows, although heterogeneity remained high. Conclusions: The current evidence does not demonstrate a consistent difference in internal fit between heat-pressed and CAD-CAM-milled lithium disilicate crowns. Further well-designed, standardized clinical studies are needed to confirm these findings.

关键词： knee arthroplasty   computational simulation   knee surgery   experimental validation   registration error   imageless navigator  

摘要： Background/Objectives: Accurate implant positioning in total knee arthroplasty (TKA) depends on reliable intraoperative landmark registration. In imageless TKA, registration errors can alter cutting-plane orientation and compromise alignment. This study quantitatively evaluated how anatomical landmark registration errors affect cutting-plane orientation in imageless TKA. Methods: A CAD-based simulation with controlled experimental validation using 3D-printed bone models was performed to reproduce the imageless TKA workflow. Controlled errors were introduced into key femoral and tibial landmarks, and the resulting deviations were quantified. The primary evaluation metrics were angular deviations in varus/valgus, flexion/extension, and internal/external rotation. Results: Coronal and rotational alignment showed the greatest sensitivity to registration error. In the femur, anteroposterior epicondylar displacement had the strongest rotational influence, with sensitivity reaching about 0.5 degrees/mm, whereas mediolateral displacement of the tibial anteroposterior landmarks showed the highest sensitivity at about 1.4 degrees/mm. Similar trends were observed in both simulation and experimental validation cases. Conclusions: The findings indicate that small registration errors can produce clinically significant cutting-plane deviations in imageless TKA, particularly at the femoral transepicondylar and tibial anteroposterior landmarks, and may approach commonly accepted alignment thresholds.

关键词： tissue engineering   chorioallantoic membrane   biocompatible materials   regeneration   periosteum   cell- and tissue-based therapy  

摘要： Despite advances in periodontal regenerative therapies, consistent tissue regeneration remains challenging, with cells playing an essential role in successful repair. Therefore, this study tested different dental bone substitutes embedded in the chorioallantoic membrane (CAM) combined with periosteum-derived micrografts obtained using a chair-side device (Rigenera HBW system). Cell populations within the micrografts were identified and characterised via immunofluorescence and flow cytometry (CD31, CD105, CD34, CD90, CD73, and CD45). A CAM model was employed to examine the angiogenic potential of micrografts combined with bone substitutes, which were analysed through quantitative blood vessel/vascularisation assessments using the Ikosa software (2025), along with histological and immunohistochemical evaluations such as smooth muscle actin (SMA), H&E, and Masson's trichrome staining. Statistical analysis was performed using GraphPad Prism 10. The addition of periosteum-derived micrografts resulted in angiogenic enhancement compared to the controls. Notable enhancement of total vessel area, total length, and branching points were obtained when Fisiograft (R) (p = 0.0007, p = 0.0002, and p < 0.0001, respectively), New Shore (R) (p = 0.0006, p = 0.0149, and p = 0.0083, respectively), and Bio-Oss (R) (p = 0.0038 and p = 0.0010, respectively) were combined with micrografts, compared to the positive controls. The histological and immunohistochemical analyses confirmed increased vascularisation (positive staining for SMA) in the micrograft groups. Periosteum-derived micrografts represent a promising adjunct to conventional bone-grafting materials, promoting vascularisation and potentially enhancing tissue regeneration and healing outcomes.

关键词： artificial intelligence   CAD-CAM   marginal fit   accuracy   occlusal contact   internal fit  

摘要： Background and Objectives: Advances in digital dentistry, particularly CAD-CAM, have improved the efficiency and precision of crown design and fabrication. Recently, artificial intelligence (AI)-integrated CAD-CAM systems have enabled automated tooth morphology generation, margin detection, and occlusal analysis, enhancing consistency and accuracy. This systematic review evaluates the accuracy of AI-assisted crown design compared with conventional and CAD-CAM workflows. Materials and Methods: A systematic search was conducted across PubMed/MEDLINE, Scopus, Web of Science, Cochrane, and LILACS for studies published between January 2010 and December 2025 that assessed the marginal fit, internal adaptation, and occlusal contact accuracy of single crowns. Screening, full-text assessment, and data extraction followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Methodological quality and risk of bias were evaluated using the Modified CONSORT checklist for in vitro studies and the Joanna Briggs Institute tools for clinical studies. Results: Of 887 records identified, 12 studies met the inclusion criteria. Nine studies showed a moderate risk of bias, two moderate-to-high, and one low-to-moderate. AI-assisted crown design demonstrated clinically acceptable internal fit and marginal adaptation, comparable or superior to CAD-CAM systems. Occlusal contact accuracy was generally comparable to CAD-CAM and technician-designed crowns, though variability was observed across AI models. Conclusions: AI-assisted crown design provides a reliable fit and marginal adaptation, with occlusal accuracy approaching conventional CAD-CAM and technician workflows. While not a replacement for clinical expertise, AI serves as a valuable adjunct, enhancing reproducibility, precision, and overall quality in restorative dentistry. Further standardized clinical studies are needed to validate long-term outcomes and optimize occlusal performance.

关键词： 图元识别   计算机视觉   目标检测   计算机辅助设计  

摘要： 图元识别是建筑图纸智能化分析与合规性评审中的关键步骤。尽管DETR(Detection Transformer)框架在通用目标检测领域展现出强大潜力,但其在建筑CAD图元识别这种特定任务中仍面临一些问题。具体而言,DETR在进行CAD图元识别时主要受限于两方面:其一,其特征提取机制对图元尺度变化的适应性不足,难以同时有效表征微小结构细节与大跨度结构信息,导致对小尺度图元漏检或对大尺度图元识别模糊;其二,由于图元有效信息在图像上分布稀疏,其注意力机制难以高效聚焦于关键区域,易受大量无效背景干扰。针对上述问题,本文在DETR框架的基础上进行三方面的改进:采用基于Swin Transformer的多尺度特征提取模块,增强模型对不同尺寸图元的鲁棒表征能力;引入空间稀疏采样注意力机制,优化特征图中有效信息的采样效率,提升关键区域的感知性能;结合对比去噪训练策略,强化模型对稀疏有效特征的定位能力。在实际建筑数据集上的实验表明,本文方法取得了0.675的mAP[0.5-0.95],显著优于现有主流目标检测模型,验证了所提方法在建筑图元识别任务上的有效性与工程实用价值。

关键词： italic>Mesembryanthemum forsskalii   facultative CAM   heat stress   drought stress   transcription factors   rhizosphere metagenome   desert plant adaptation   thermotolerance  

摘要： Introduction Dryland ecosystems are increasingly exposed to extreme heat and prolonged water limitation. Facultative crassulacean acid metabolism (CAM) enables certain desert plants to enhance water-use efficiency and adjust carbon assimilation under stress conditions. Mesembryanthemum forsskalii Hochst. ex Boiss. (Aizoaceae;locally known as Samh) is a hyper-arid adapted species native to Saudi Arabia, yet genomic and transcriptomic resources for this plant remain scarce. This study aimed to generate foundational genomic resources and characterize transcriptional responses to drought and heat *** We integrated rhizosphere metagenomics and leaf transcriptomics. A genome-resolved rhizosphere metagenome was generated from mature field-grown plants. In parallel, micropropagated plants were exposed under controlled conditions to progressive drought (17 days without irrigation) or acute heat shock (55 degrees C for 120 min), each compared with well-watered controls. RNA sequencing generated 123.77 Gb raw data and 121.96 Gb clean reads after quality filtering. Differential gene expression was identified using thresholds of |log2FC| >= 2 and FDR <= 0.05, followed by transcription factor profiling and KEGG pathway *** Heat stress induced substantially broader transcriptional reprogramming than drought. A total of 1,348 genes were differentially expressed under heat stress, compared with 84 genes under drought. Heat exposure strongly increased the expression of transcription factor families including B3 (20.00-fold relative to drought), bHLH (22.65-fold), and bZIP (8.94-fold). KEGG pathway analysis revealed expanded representation of metabolic pathways under heat, including secondary metabolite biosynthesis, ribosome function, carbon metabolism, and endoplasmic reticulum protein processing. Rhizosphere binning recovered archaeal and bacterial genomes affiliated with stress-tolerant lineages, providing the first microbial genomic framework associated

关键词： Antiplatelets   CAD   Infection   Thrombosis   Bleeding   Antiplatelets   P2Y12   CAD   Infection   Thrombosis   Bleeding  

关键词： CAD/CAM crowns   3D printing   additive manufacturing   conservative dentistry   occlusal thickness   dental materials  

摘要： This in vitro study evaluated the fracture resistance of CAD/CAM-fabricated lithium disilicate and 3D-printed resin crowns with varying occlusal thicknesses (0.5, 1.0, and 1.5 mm) following thermomechanical aging. Sixty extracted human molars were assigned to six experimental groups (n = 10), categorized by crown material and occlusal thickness. The crowns were fabricated using CAD/CAM technology in accordance with the manufacturer's protocol. All specimens underwent thermomechanical aging, which consisted of thermocycling between 5 and 50 degrees C (5500 cycles) combined with mechanical loading of 50 N at 1.6 Hz for 75,000 cycles. The fracture loads were measured using a universal testing machine, and the failure modes were assessed using scanning electron microscopy. Statistical evaluation was performed using two-way analysis of variance with Tukey's post hoc test (alpha = 0.05). Both the material type and occlusal thickness had a statistically significant effect on fracture resistance (p < 0.001). Lithium disilicate crowns exhibited higher fracture loads than 3D-printed resin crowns independent of occlusal thickness. Although the fracture resistance of 3D-printed resin crowns was lower, specimens with occlusal thicknesses >= 1.0 mm exhibited fracture loads exceeding average physiological masticatory forces, suggesting that 3D-printed resin crowns may represent a clinically acceptable option for conservative posterior restorations. In contrast, crowns with an occlusal thickness of 0.5 mm demonstrated fracture resistance values below the reported functional masticatory loads. Additionally, the proportion of repairable fractures increased with increasing occlusal thickness for both materials. Overall, the findings suggest that an occlusal thickness of at least 1.0 mm may represent a reliable threshold for posterior restorations, whereas a thickness of 0.5 mm may be insufficient to withstand functional occlusal loads in molar regions.

关键词： Biodiversity monitoring   Ensemble learning   Honey yield   Machine learning   Precision agriculture   Sustainable agriculture  

摘要： This study presents an adaptive framework for the incipient detection of wax moth (Galleria mellonella) outbreaks in honeybee hives by integrating deep learning and machine learning within smart farming systems. A custom dataset of 3252 high-resolution images collected from honey bee apiaries in Rahim Yar Khan, Pakistan (May–August 2024) encompasses labeled samples of healthy hives and infestation, further categorized into stages (Larva, Pupa, and Adult), enabling hierarchical classification as Main and Subclass. Features were extracted incorporating Transfer Learning with a pre-trained VGG16 network, followed by training classical and ensemble machine learning classifiers, comprising Random Forest, Logistic Regression, Support Vector Machine, K-Nearest Neighbours, and advanced Voting and Stacking ensembles. Performance was evaluated utilizing quantitative measures, notably accuracy, precision, recall, F1-score, specificity, MCC, and ROC AUC, with validation via ten-fold cross-validation. For Main class, the proposedXAI-HoneyNetensemble attained test accuracy of 0.99, ROC AUC of 0.9994, and mean tenfold cross-validation accuracy of 0.9892. Alongside this, Cohen’s Kappa was 0.9719, the one-sample t-test yielded\(t = 225.8625\)(\(p < 0.0001\)), and the ANOVA comparing Voting and Stacking classifiers reported\(F = 0.0184\)(\(p = 0.8936\)). For subclass categorization,XAI-PestNetsecured 96% accuracy with strong MCC and ROC AUC scores. To ensure model transparency and interpretability, SHapley Additive exPlanations (SHAP) and Gradient-weighted Class Activation Mapping (Grad-CAM) were employed, showcasing critical features and visual cues that drove predictions. To conclude, the proposed XAI-HoneyNet and XAI-PestNet offer a smart hybrid explainable AI framework for hierarchical infestation detection and pest classification in precision agriculture.