Tumors in the oral and maxillofacial region present significant clinical challenges due to anatomical complexity and high individual variability, with the traditional experience-dependent model often lacking three-dimensional visualization, precise intraoperative navigation, and quantitative postoperative assessment. This article comprehensively reviews over a decade of research and clinical advances in "digital and intelligent surgery" developed by our team at Peking University School and Hospital of Stomatology, systematically documenting its transformative impact on tumor management. In digital surgery, we have established multimodal image fusion techniques integrating CT, MRI, and PET/CT to achieve detailed three-dimensional preoperative visualization, enabling accurate delineation of tumor boundaries and relationships with critical anatomical structures, such as nerves and vessels. We further developed personalized surgical planning methods including virtual design for jaw reconstruction using vascularized fibula or iliac crest flaps, computer-aided pre-forming of orbital titanium mesh, 3D-printed patient- specific plates manufactured via electron beam melting, soft-tissue flap simulation and volumetric planning for the anterolateral thigh flap, and implant-guided rehabilitation for complex maxillary defects. For surgical execution, navigation systems and mixed reality technologies have been implemented to enable accurate tumor resection, osteotomy guidance, and precise positioning of reconstructed bone segments, thereby enhancing surgical accuracy and safety while reducing operative time. In parallel, artificial intelligence has been integrated to enhance diagnostic and planning efficiency through deep learning-based tumor segmentation and classification from enhanced CT and MRI, automated reconstruction planning based on shape completion and morphometric descriptors, postoperative facial contour prediction using surface mesh deformation models, and machine learning-driven prognostic modeling for salivary gland malignancies based on clinicopathological data. The synergistic integration of these digital and intelligent technologies, collectively termed "digital and intelligent surgery", has shifted clinical practice from an experience-driven to a data-driven paradigm, significantly improving precision, safety, and efficiency while enabling truly personalized treatment pathways. This review also identifies current limitations such as the need for further automation in soft-tissue simulation and broader clinical validation of AI tools, and outlines future directions including the development of integrated surgical platforms and real-time adaptive planning systems, emphasizing the role of intelligent surgical systems in shaping the next generation of oral and maxillofacial oncology care toward more predictive, preventive, and patient-centered outcomes. 发生于口腔颌面部的肿瘤因解剖结构复杂且个体差异大, 传统"经验依赖型"诊疗模式存在术前规划无法三维可视化、术中缺少精准导航、术后缺乏量化评估等局限性。本文系统综述了本课题组十余年来在口腔颌面部肿瘤"数智化外科"领域的探索与临床应用成果。在数字化外科方面, 课题组建立了基于CT、MRI、PET/CT等多模态数据融合的术前三维可视化技术, 开发了颌骨缺损重建、眶底钛网预成形、3D打印个性化钛板、软组织皮瓣虚拟设计与种植修复等个性化手术方案设计方法, 并将外科导航系统、混合现实技术应用于术中精准定位与肿瘤切除。在人工智能应用方面, 课题组探索了基于深度学习的肿瘤影像自动分割与分类、颌骨重建方案自动生成、术后面型预测及唾液腺恶性肿瘤预后评估等智能化技术。通过数字化与智能化技术的深度融合, "数智化外科"实现了从经验驱动到数据驱动的诊疗模式转型, 显著提升了口腔颌面部肿瘤诊疗的精准性、安全性和效率, 为患者提供了更加个性化、可预测的治疗方案。本课题组还展望了未来"数智化外科"在口腔颌面部肿瘤诊疗中的发展方向。
In response to recent advances in computer-aided drug discovery (CADD) enabled by high-performance computing, computational approaches were employed to support and rationalize the investigation of a VEGFR-2-targeted anticancer candidate, combining molecular-level modeling with experimental validation. Initial in silico ADMET profiling and molecular docking were conducted to support the evaluation of drug-like properties and target engagement within a series of para-toluidine-based derivatives (1-14). The most biologically active compound was further evaluated through 100 ns molecular dynamics simulations and comprehensive DFT calculations to investigate binding stability and electronic characteristics. Based on a rational design strategy and supported by computational analyses, the compounds were synthesized and fully characterized using IR, MS, 1H/13C NMR, and elemental analysis. Biological evaluation was performed against HepG-2, MCF-7, HCT-116, and normal WI-38 cells. Mechanistic studies included VEGFR-2 inhibition, wound-healing migration assays, cell-cycle distribution analysis, apoptosis assessment, and caspase-3 activation. Several derivatives exhibited micromolar cytotoxic activity, with compound 14 emerging as the most active against HepG-2 cells (IC50 = 7.84 ± 0.5 µM), showing cytotoxic activity comparable to that of sorafenib (IC50 = 9.18 ± 0.6 µM) and demonstrating favorable selectivity toward normal WI-38 cells (IC50 = 67.75 ± 3.6 µM). Compound 14 showed moderate VEGFR-2 inhibitory activity (IC50 = 0.55 µM), significant suppression of cell migration, pronounced G0/G1 cell-cycle arrest, and robust apoptosis induction supported by caspase-3 activation. Molecular docking and MD simulations supported a stable binding mode within the VEGFR-2 active site. This integrated framework highlights compound 14 as a selectively active VEGFR-2-oriented anticancer candidate scaffold with a favorable selectivity profile, supported by experimental and computational analyses, warranting further lead optimization.
The objective of this study was to compare changes in the surface roughness and color of 2 types of resin formulated for 3-dimensional (3D) printing and 1 resin formulated for computer-aided design/computer-aided manufacturing (CAD/CAM) following immersion in coffee solution or distilled water and subsequent brushing. Cylindrical specimens were 3-printed with standard or long-term provi-sional resins or milled from CAD/CAM resin blocks (n = 22 per material). After polishing, baseline surface roughness (Ra) and color parameters (CIE L*a*b* and CIEDE2000) were recorded. For 30 days, half of the specimens of each material (n = 11) were immersed in a fresh coffee solution for 3 hours, while the other half were immersed in distilled water. All specimens were then submitted to 16,200 brushing cycles to simulate aging, and surface roughness and color parameters were remeasured. The data were compared according to restorative material, immersion solution, and measurement time using the Kruskal-Wallis and Dunn, Mann-Whitney U, and Wilcoxon tests, respectively, at a significance level of 5%. The surface roughness of the standard 3D-printed resin and the CAD/ CAM-milled resin increased significantly following immersion in distilled water (P < 0.05), but only the milled resin showed a significant increase in surface roughness after immersion in coffee (P < 0.05). For both 3D-printed resins, coffee immersion resulted in significantly greater color change than water immersion (P < 0.05). No significant color change differences among materials were observed after immersion in distilled water (P > 0.05). However, the CAD/CAM--milled resin showed significantly less color change than both 3D-printed resins following immersion in coffee (P < 0.05). The surface roughness of the long-term 3D-printed resin remained stable after aging. Immersion in coffee caused a more visible color change in the 3D-printed resins than in the CAD/CAM--milled resin.
This study aimed to develop a dysphagia-friendly surimi gel with optimum moisture (80%-95%) and omega-3-enriched shrimp oil (5%-20%; n3SO) content via the application of 3D food printing technology. The higher printability and structural stability were noticed at 90% moisture level as observed by higher shape retention (87%) and stability (100%). Then gel printed at selected moisture content showed decreased hardness, cohesiveness, chewiness, and viscoelastic properties with increasing oil levels. Among which, 10% n3SO provides the optimal balance of softness and consumer acceptability. Viscoelastic properties also supported the textural properties, in which increasing oil levels showed reduction in elastic and loss modulus. When 3D printing parameters, including medium (MLR), coarse (CLR) and extra coarse (ECLR) layer resolutions and nozzle diameter (1.5, 2.5, and 3.5 mm), were evaluated to print the gel. In which, MLR combined with a 3.5 mm nozzle produced gels with the lowest hardness (485.56 ± 0.61 g) and expressible moisture content (4.27 ± 0.03%). The Pearson correlation analysis also concluded that the 3.5 mm provides a practical balance between printability and structural integrity (chewiness/hardness). Confocal laser scanning microscopy revealed uniform lipid and protein distribution. In addition, cooking methods also influenced gel characteristics as observed by hardness, with steaming yielding softer gels (485.56 ± 0.61 g), microwaving producing intermediate textures (496.07 ± 1.01 g), and air frying leading to firmer (624.11 ± 2.01 g) and dehydrated gels. The optimized steamed gel was classified as IDDSI Level 5 (minced and moist), indicating safe swallowing. Thus, 3D-printed surimi gel with 90% moisture and 10% n3SO achieved IDDSI Level 5, offering a nutrient-rich, dysphagia-friendly food with good printability and texture.
To evaluate the flexural strength, monomer release, and wear resistance between conventional, milled polymethylmethacrylate (PMMA), and 3D-printed resins built at 90° and 60° printing angles for occlusal splints. 60-rectangular and 100-disc specimens were fabricated from heat-cured PMMA (Oracryl [HP], Bracon Dental, United Kingdom), milled PMMA (Kerox Premia [KP], Kerox Dental, Hungary), and 3D-printed resins (FreePrint Splint2.0 [FS], Detax, Ettlingen, Germany, and KeySplint Hard [KS], Keystone Industries, Myerstown, USA) at 90° and 60° printing angles. Specimens for flexural strength and wear tests were immersed immediately in 37°C water for 50 h and thermally aged for 20,000 cycles. Flexural strength was evaluated using a three-point bend test. Wear was tested using a chewing simulator for 140,000 cycles, and volume loss was calculated using Autodesk MeshMixer software. Monomer release was analyzed via UV spectrophotometry over 7 days. Statistical analysis was performed using the Shapiro-Wilk test and one-way ANOVA with Tukey's multiple comparison tests. KP showed the highest mean flexural strength (115.5 ± 5.3 MPa, p < 0.0001), followed by HP (86.6 ± 10.8 MPa, p < 0.0001), with 3D-printed resin showed the lowest. Meanwhile 90° FS showed greater flexural strength (60.5 ± 3.8 MPa) compared to 60° FS (p < 0.001) and KS (p < 0.01). The difference between 90° and 60° KS were not statistically significant (p > 0.05). Monomer release peaked on Day 3 for all groups, with KS consistently showing the highest concentration (29.7 ± 3.6 ppm), followed by FS (28.8 ± 3.8 ppm), HP (27.9 ± 4.9 ppm), and lastly, KP showed the lowest concentration (24.9 ± 3.8 ppm). KP demonstrated the lowest mean volume loss (2.5 ± 1.3 mm3, p < 0.01), followed by HP (4.4 ± 1.7 MPa), whereas 3D-printed resin showed the highest. No significant wear differences were observed between 90° and 60° printing angles. Milled PMMA outperformed other materials, followed by conventional PMMA, while 3D-printed resin showed inferior performance in flexural strength, wear resistance, and monomer release. Printing angles significantly influenced flexural strength but not wear properties in 3D-printed resins.
Diabetic ulcers are complex wounds that are difficult to treat due to persistent inflammation, excessive oxidative stress, impaired angiogenesis, and microbial infections that disrupt normal healing. Advanced wound dressings such as hydrogels, nanofibre matrices, hydrocolloids, and 3D bioprinted constructs are increasingly developed to incorporate natural bioactive compounds with multifunctional therapeutic properties. However, systematic understanding of their mechanisms and translational relevance remains limited. This study aims to systematically review natural-based hydrogel, hydrocolloid, and hydrofiber formulations in diabetic wound healing. A Systematic Literature Review following PRISMA guidelines was conducted using ScienceDirect, SpringerLink, PubMed, and Scopus (2020-2025). Risk of bias was assessed using SYRCLE's tool. From 5256 initial records, 4412 articles were screened, and 14 studies were included after applying eligibility criteria. These studies examined advanced dressings such as hydrogels, hydrocolloids, nanofibers, 3D bioprinted constructs, and hybrid nanocomposites incorporating natural bioactive compounds. The formulations demonstrated antimicrobial, anti-inflammatory, antioxidant, pro-angiogenic, and re-epithelialization effects. Common compounds included curcumin, berberine, propolis, bee venom, and plant extracts combined with polymers such as chitosan, alginate, hyaluronic acid, collagen, and GelMA. Advanced fabrication improved drug delivery, physicochemical properties, and healing outcomes. At the molecular level, these systems modulated pathways such as NF-κB, PI3K/Akt, MAPK, VEGF, and TGF-β/Smad, contributing to reduced inflammation, oxidative stress suppression, enhanced angiogenesis, and extracellular matrix remodeling. Risk of bias assessment indicated unclear risks in randomization and blinding, although internal validity was generally acceptable Translational readiness remained limited (TRL 2-6), with hydrogels and nanosystems showing the highest potential, while 3D bioprinting faces scalability and regulatory challenges. Natural-based advanced dressings offer a promising strategy for diabetic wound management. Successful clinical translation requires alignment with scalability, stability, cost-effectiveness, and regulatory compliance. Future research should prioritize standardized preclinical models, controlled release systems, and scalable, regulation-compliant biomaterial designs to accelerate clinical application.
The objective of this study was to compare the accuracy of 2 root canal impression techniques used to obtain digital models for post and core restorations in a computer-aided design/computer-aided manufacturing process. Cone beam computed tomography and segmentation software were used to calculate the post space (PS) volume of a decoronated, endodontically treated bovine tooth. Measurements were performed 10 times to obtain a mean reference value that served as the control. A benchtop dental scanner was used to scan 10 impressions made with polyvinyl siloxane (PVS) and 10 made with chemically activated acrylic resin (CAAR) to obtain 3-dimensional digital models, whose volumes were measured with mesh processing software. The 1-sample t test was used to compare the mean volume of each test impression group with the control PS volume (trueness), and the t test for independent samples was used to compare the test groups with each other (precision). The dispersion, variance, and standard deviation were analyzed (α = 0.05). The mean (SD) control PS volume was 84.11 (0.15) mm3, while the volume of the CAAR group was 78.70 (2.33) mm3, and the volume of the PVS group was 86.20 (2.08) mm3. The difference between the PS volume and the volume of each test group was statistically significant (CAAR, P < 0.001; PVS, P = 0.011), and the volumes of the test groups were significantly different from each other (P < 0.001). The variance was 5.42 mm3 in the CAAR group and 4.32 mm3 in the PVS group. While both materials showed some distortion, the results suggest that the PVS technique generates more accurate digital models than the CAAR technique, with values that more closely approach the reference PS volume and exhibit less variation in successive measurements.
A calcium ion cross-linked sodium alginate-anthocyanin pH-responsive label was fabricated via 3D printing and evaluated for monitoring fruit and vegetable freshness during storage. Gradient sensors constructed with purple sweet potato anthocyanins for operation across a pH range of 9-12 exhibited dense microstructures, good structural integrity, and high environmental stability. During cold storage of five representative fruits and vegetables, the sensors displayed distinct ΔE color responses to variations in CO₂ concentration and relative humidity (RH). The gradient design enabled graded and intuitive visual color transitions, allowing stepwise freshness indication. High-respiration produce (mushrooms and broccoli) induced pronounced acidification responses in sensors conditioned at pH 9 and 10, whereas sensors conditioned at pH 12 exhibited fading due to pigment instability under alkaline and high-RH conditions. For moderate- and low-respiration crops (peppers, blueberries, and grapes), sensor responses reflected combined effects of CO₂ release and moisture-induced degradation. Across all samples, ΔE inflection points or stabilization typically occurred at days 4-6 (CO₂-dominated stage) or days 10-12 (humidity-dominated stage), demonstrating the sensor's adaptability and effectiveness in tracking freshness deterioration. This work addresses the stability limitations of anthocyanin-based sensors under alkaline conditions and provides a scalable, visual, and real-time freshness monitoring platform for intelligent packaging applications under realistic high-humidity storage conditions.
Three-dimensional (3D) bioprinting integrates engineering, materials science, and biology to fabricate living tissues with precise spatial control. By enabling the layer-by-layer deposition of cells and biomaterials, it overcomes many limitations of traditional scaffold-based tissue engineering and offers new opportunities for regenerative and personalized medicine. This review presents a comprehensive overview of recent advances in 3D bioprinting. It introduces a systematic, ASTM-aligned classification of key bioprinting modalities, extrusion, jetting, and vat photopolymerization, along with their respective material and biological design requirements. It also summarizes recent progress in bio-ink development and crosslinking strategies that improve print fidelity and functional tissue maturation. In addition, the review highlights applications in both systemic disease modelling and treatment (such as cardiovascular, endocrine/metabolic, and neurodegenerative disorders) and localized tissue repair (including skin, musculoskeletal, cartilage, and bone), emphasizing their relevance to civilian healthcare and military medicine. By combining technological innovation, biological insights, and regulatory considerations, this review outlines how advances in multi-modal bioprinting and intelligent process control can accelerate the translation of laboratory research into clinically viable, patient-specific therapies, driving the next generation of regenerative medicine.
Intraoral scanners (IOS) are widely used in digital implant workflows, and their accuracy is typically evaluated in vitro using reference bodies to establish a coordinate system. While the impact of scanning strategy and evaluation methods on accuracy is well documented, the potential effect of the spatial position of the reference body itself on measured transfer accuracy has not been systematically investigated yet. This study aimed to evaluate whether the position of a reference body within a master model affects linear and three-dimensional (3D) accuracy outcomes of intraoral scan data. A partially edentulous maxillary implant master model with four implants (FDI #16, #14, #25, and #26) and two perpendicular cuboid-shaped reference bodies was scanned ten times each using Trios 4 and Primescan AC IOS. Each dataset was evaluated twice by aligning it either to reference body 1 (REF-1) or reference body 2 (REF-2), generating paired measurements from identical scans. Linear distances between implant-abutment interface points and 3D deviations from the reference bodies were calculated. Trueness and precision were assessed according to ISO 5725-1, and paired statistical comparisons were performed. Differences between REF-1 and REF-2 were evaluated by paired t-tests for trueness and variance-related tests for precision, with a significance level set at α = 0.05. For both scanners, significant differences in trueness were observed between REF-1 and REF-2 for several linear distances and three-dimensional deviations (p < 0.05), despite identical scan datasets. Reference-dependent effects were more pronounced for three-dimensional deviations than for linear measurements. For selected distances, significant differences in precision were also detected (p < 0.05). The position of the reference body within a model significantly influences measured linear and 3D implant accuracy, independent of the IOS system used. Alignment reference position represents an independent source of systematic bias in digital accuracy assessments. These findings should be considered when designing, interpreting, and comparing accuracy studies in digital implant dentistry.
The global shortage of donor organs and the limitations of conventional in vitro models stress the urgent need for advanced liver tissue engineering and regenerative medicine strategies. These approaches aim to create physiologically relevant platforms for drug testing and develop transplantable tissues to restore liver function. Decellularization offers unique advantages by providing native extracellular matrix architecture and biochemical cues that support cell adhesion, differentiation, and vascularization. Complementary technologies such as three-dimensional (3D) bioprinting and microfluidics enable precise spatial organization of multiple cell types and dynamic perfusion, improving tissue functionality and disease modeling. Together, these innovations facilitate the development of high-fidelity liver constructs and organ-on-chip systems for studying pathologies like fibrosis and steatosis, as well as for preclinical drug screening. In this review we summarize current methods for liver decellularization and explore its role as a regenerative medicine strategy. We also examine applications in disease modeling, with emphasis on 3D bioprinting and microfluidic platforms, and discusses emerging vascularization techniques. Collectively, these insights highlight the progress and remaining challenges in engineering functional liver tissues for clinical and research applications.
Magnetic adsorbents are widely employed in sample preparation, but magnetic solid-phase extraction (MSPE) still faces limitations related to magnet handling and pipetting, which increase time, variability, and operational costs. To overcome these drawbacks, we developed a 3D-printed magnetic removable-cap extraction device aimed at simplifying manipulation, improving reproducibility, and minimizing solvent consumption in the extraction step. As a proof of concept, a restricted-double-access magnetic polypyrrole adsorbent was synthesized, characterized, and applied to the extraction of nifedipine (NDP) and nimodipine (NMDP) from human plasma prior to chromatographic analysis. The magnetic adsorbent was evaluated using the 3D-printed magnetic removable-cap device and compared with conventional MSPE approaches. Structural and morphological characterization confirmed its mesoporous and hydrophobic properties, together with strong macromolecule exclusion. After optimization, both extraction formats demonstrated suitable precision and accuracy, while the 3D-printed device provided a faster workflow and simpler operation. Optimal conditions involved 15 mg of adsorbent, 250 μL of plasma at pH 10.0, 1000 μL of methanol for elution, and 60 s of agitation. The HPLC-UV method showed linearity from 100 to 3500 ng mL-1, with adequate selectivity and accuracy. The limits of detection and quantitation were 50 and 100 ng mL-1, respectively, and protein removal reached 93%. The magnetic adsorbent was reusable for up to three extraction cycles without loss of performance. Coupling the 3D-printed device with the magnetic adsorbent enabled efficient, selective, and reproducible determination of NDP and NMDP in human plasma while minimizing sample handling and solvent use. Green analytical metrics confirmed this workflow as an eco-friendly, rapid, and reliable alternative for bioanalytical sample preparation.
This study aimed to evaluate the impact of varying degrees of anterior diastema and crowding on the precision of 3D-printed dental models using digital superimposition techniques. A digital maxillary arch model was modified in the anterior region (canine to canine) to simulate three levels of diastema (2.5 mm, 5 mm, 10 mm) and four levels of crowding (3 mm, 6 mm, 9 mm, 12 mm), along with an unmodified control. Eight digital models were fabricated using LCD 3D printing, with 15 prints per group. Printed models were scanned and superimposed onto their respective reference models using Geomagic Control X. Surface deviations were analyzed via minimum, maximum, root mean square (RMS), and average positive and negative values. One-way ANOVA and Tukey's HSD post-hoc test were used for statistical evaluation. Significant differences were observed among diastema groups (p < 0.05), with the 5 mm group showing the widest deviation range. RMS and average deviation values were highest in the 2.5 mm and 5 mm diastema conditions. In the crowding groups, significant deviations in minimum and maximum values occurred only in the 12 mm group (p < 0.001 and p < 0.008, respectively). Severe anterior crowding (12 mm) and mild to moderate diastemas (≤5 mm) significantly impair the precision of 3D-printed dental models. These results highlight the importance of assessing digital model fidelity in cases with anterior spacing or crowding, to ensure accurate diagnosis and appliance fabrication. Este estudo teve como objetivo avaliar, utilizando técnicas de sobreposição digital, o impacto de diferentes graus de diastema anterior e apinhamento na precisão de modelos dentários impressos em 3D. Um modelo digital da arcada superior foi modificado na região anterior (canino a canino) para simular três níveis de diastema (2,5 mm, 5 mm, 10 mm) e quatro níveis de apinhamento (3 mm, 6 mm, 9 mm, 12 mm), juntamente com um controle não modificado. Assim, oito modelos digitais foram fabricados utilizando impressão 3D LCD, com 15 impressões por grupo. Os modelos impressos foram escaneados e sobrepostos aos seus respectivos modelos de referência, utilizando o software Geomagic Control X. Os desvios de superfície foram analisados por meio dos valores mínimo, máximo, raiz quadrada média (RMS) e média dos valores positivos e negativos. Para avaliação estatística, foram utilizados os testes ANOVA de uma via e post-hoc HSD de Tukey. Foram observadas diferenças significativas entre os grupos com diastema (p < 0,05), sendo que o grupo de 5 mm apresentou a maior amplitude de desvio. Os valores de RMS e desvio médio foram mais elevados nas condições de diastema de 2,5 mm e 5 mm. Nos grupos com apinhamento, desvios significativos nos valores mínimo e máximo ocorreram apenas no grupo de 12 mm (p < 0,001 e p < 0,008, respectivamente). O apinhamento anterior severo (12 mm) e os diastemas leves a moderados (≤5 mm) comprometem significativamente a precisão dos modelos dentários impressos em 3D. Esses resultados destacam a importância de se avaliar a fidelidade do modelo digital em casos de diastema anterior ou apinhamento, para garantir um diagnóstico preciso e a confecção adequada de aparelhos ortodônticos.
To evaluate the positional accuracy of dynamic navigation-assisted trephine bone harvesting in the symphysis and external oblique ridge. Ten standardized mandibular models were 3D-printed using polyetheretherketone (PEEK), mimicking natural mandibular mechanical properties. Pre-operative cone beam CT (CBCT) scans (70 kV, 70 mA, 0.25 mm×0.25 mm ×0.25 mm voxel) were acquired, and data were imported into dynamic navigation software (Dcarer, China). Two donor sites were designed in both the symphysis (≥15 mm from anterior teeth) and external oblique ridge (≥6 mm from molars), with 8 mm-diameter, 6 mm-deep cylindrical osteotomy tracts planned for each site.After calibrating the navigation system with 20 mm and 50 mm spherical burs, an 8 mm outer-diameter trephine prepared 40 tracts under real-time guidance. Post-operative CBCT scans were taken, and Mimics 20.0 software fitted actual tracts to standard cylinders. Superimposing actual and designed tracts via metal registration markers, we measured coronal/apical center point deviation, depth deviation, and axis angle deviation in order to compare site-specific accuracy. Deviations of the dynamic navigation-assisted trephine method for bone harvesting was (1.91±0.69) mm at the coronal center point, (1.54±0.66) mm at the apical center point, (－0.83±0.77) mm at the depth of the apical center point and 3.02°±0.38° at the axis angle. The four deviations in symphysis and external oblique ridge were (1.32±0.36) mm and (2.50±0.35) mm at the coronal center point (P < 0.01), (1.06± 0.31) mm and (2.02±0.56) mm at the apical center point (P < 0.01), (－0.30±0.52) mm and (－1.38±0.57) mm at the depth of apical center point (P < 0.01), 3.03°± 0.38° and 3.00°± 0.39° at axis angle (P=0.80). Within the limitations of this study, dynamic navigation-assisted trephine harvesting shows good accuracy. The symphysis exhibits higher accuracy than the external oblique ridge, possibly due to surface morphology and operability differences. These findings support its clinical potential, but future clinical studies are needed to validate results. 评估在颏部和外斜线区域使用动态导航辅助环钻法取骨的准确性。 设计并使用3D打印技术以聚醚酮酮(polyetheretherketone, PEKK)材料制作10个标准下颌骨模型以模拟天然下颌骨的力学性能。实验前拍摄模型的锥形束CT(cone beam CT，CBCT)，参数设定为管电压70 kV、管电流70 mA、体积像素250 μm。将数据导入动态导航软件(迪凯尔公司，中国)，并在颏部(距前牙≥15 mm)和外斜线区域(距磨牙≥6 mm)各2个常规手术位点设计具有相同深度(6 mm)和直径(8 mm)的圆柱形预备道。使用20 mm和50 mm长度的球钻完成导航系统标定后，在动态导航辅助下于每个位点使用8 mm外径的环钻完成共计40个位点的预备道制备。拍摄术后模型的CBCT，利用Mimics 20.0软件(Materialise公司，比利时)将实际预备道拟合成标准圆柱体，并基于金属配准标记将实际预备道与设计预备道叠加，测量进入中心点偏差、结束中心点偏差、深度偏差及中心轴角度偏差，比较不同供区的准确性差异。 动态导航辅助环钻取骨的进入及结束中心点误差分别为(1.91±0.69) mm和(1.54±0.66) mm，深度误差为(－0.83±0.77) mm，中心轴角度差为3.02°±0.38°，其中在颏部和外斜线的进入中心点误差分别为(1.32±0.36) mm和(2.50±0.35) mm(P＜0.01)，结束中心点误差分别为(1.06±0.31) mm和(2.02±0.56) mm(P＜0.01)，深度误差分别为(－0.30±0.52) mm和(－1.38±0.57) mm(P＜0.01)，中心轴角度差分别为3.03°±0.38°和3.00°±0.39°(P=0.80)。 在本研究的局限性范围内，动态导航辅助环钻取骨有着良好的准确性表现，其中颏部取骨准确性优于外斜线区域，这可能与两个区域的骨表面形态及手术操作等因素的差异有关；本研究结果为动态导航辅助环钻法取骨技术的临床应用提供了参考数据，但仍需要后续临床研究进一步验证其准确性。
To evaluate effectiveness of three-dimensional (3D) printed patient-specific cutting guides (PSCGs) in Cole midfoot osteotomy for treatment of rigid pes cavus deformity associated with Charcot-Marie-Tooth (CMT) disease, and to analyze learning curve for PSCGs-assisted surgery. A retrospective analysis was conducted of 20 patients (40 feet) with rigid pes cavus deformity associated with CMT who were admitted between March 2021 and July 2023 and met the inclusion criteria. The cohort comprised 13 men and 7 women, with ages ranging from 17 to 62 years (mean, 37.3 years). All patients underwent whole-genome sequencing, which identified 17 patients with CMT type 1 and 3 patients with CMT type 2. Preoperatively, 3D models of bilateral feet were reconstructed based on CT data, and PSCGs were designed and fabricated accordingly. All patients underwent a Cole midfoot osteotomy assisted by the guides. Operation time, number of intraoperative fluoroscopic exposures, and intraoperative complications were recorded. Pre- and post-operative outcomes were compared using the visual analogue scale (VAS) score for pain, the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and domain scores of the 36-Item Short Form Health Survey (SF-36), as well as radiographic parameters including the Meary's angle, Pitch angle, talo-first metatarsal angle (T1MT), talocalcaneal angle (TCA), and Djian-Annonier angle, to assess the corrective effect of the osteotomy. A modified cumulative sum analysis was performed to evaluate the learning curve for PSCGs-assisted surgery. All procedures in the 20 patients (40 feet) were completed successfully, with no cases of massive hemorrhage or injury to critical neurovascular or tendinous structures. The operation time ranged from 63 to 129 minutes (mean, 82.9 minutes), and fluoroscopy was performed 2-11 times (mean, 4.7 times). Postoperatively, 1 patient (1 foot) developed a mild superficial surgical-site infection, which resolved with symptomatic treatment; no deep infections occurred. All patients were followed up 8-43 months (mean, 17 months). At last follow-up, the AOFAS ankle-hindfoot score and all domain scores of the SF-36 were significantly higher than preoperative values, and the VAS score, the Meary's angle, T1MT, TCA, and Djian-Annonier angle significantly decreased, Pitch angle significantly increased ( P<0.05). The imaging confirmed osteotomy union in all feet, and no fixation-related complications was observed. Learning-curve analysis indicated that both operation time and fluoroscopy usage plateaued after the 13th case, suggesting stabilization of surgical performance from that point onward. The use of PSCGs during Cole midfoot osteotomy enables precise and efficient correction of complex midfoot deformities while significantly reducing intraoperative fluoroscopic exposure. Moreover, this technique appears to have a short learning-curve and good reproducibility, which may facilitate its broader adoption in clinical practice. 探讨3D打印个体化截骨导板（patient-specific cutting guides，PSCGs）辅助中足Cole截骨术治疗Charcot-Marie-Tooth综合征（CMT）相关僵硬型高弓足的临床疗效及其学习曲线。. 回顾性分析2021年3月—2023年7月收治且符合选择标准的20例（40足）CMT相关僵硬型高足弓患者临床资料。男13例，女7例；年龄17～62岁，平均37.3岁。全部患者均完善全基因组检测，其中CMT 1型17例、2型3例。术前均基于患者足部CT扫描数据构建足部三维模型并设计制备PSCGs，术中于导板辅助下行中足Cole截骨术。记录手术时间、术中透视次数及术中并发症等。比较手术前后疼痛视觉模拟评分（VAS）、美国矫形足踝协会（AOFAS）踝-后足评分、简明健康调查量表（SF-36量表）各维度评分，以及Meary角、足弓倾斜角（Pitch角）、距骨-第1跖骨角（talo-first metatarsal angle，T1MT）、距跟角（talocalcaneal angle，TCA）、足内侧纵弓角（Djian-Annonier角），评价截骨矫正效果。采用修正累积和分析法评估PSCGs辅助手术学习曲线。. 20例（40足）手术均顺利完成，术中未发生大出血或重要结构损伤。手术时间63～129 min，平均82.9 min；术中透视2～11次，平均4.7次。术后1例（1足）发生轻度切口浅表感染，经对症处理后愈合；均无深部感染发生。患者均获随访，随访时间8～43个月，平均17个月。末次随访时，AOFAS踝-后足评分、SF-36量表各维度评分均较术前提高，VAS评分降低，差异有统计学意义（ P<0.05）；X线片测量示Meary角、T1MT、TCA、Djian-Annonier角均较术前减小，Pitch角增大，差异亦有统计学意义（ P<0.05）。截骨均已愈合，无内固定相关并发症发生。学习曲线分析示PSCGs辅助手术时间和透视次数自第13例起趋于稳定。. 中足Cole截骨术中采用PSCGs辅助截骨，可实现对复杂中足畸形精准且高效的矫正，显著减少术中放射暴露。同时该技术学习周期较短、可复制性良好，有利于其临床推广。.
Three-dimensional (3D) printing has accelerated the development of customized medical devices, but biofilm formation on printed materials remains a major threat to implant safety and performance. Because material chemistry and print-dependent surface features can influence bacterial attachment and antibiotic tolerance, standardized in vitro approaches that enable meaningful comparisons across commonly used 3D-printing polymers are needed. Here, we compare biofilm development on polylactic acid (PLA) and polyethylene terephthalate glycol (PETG) using a multi-model in vitro evaluation framework that captures complementary aspects of biofilm biology, including early adhesion, maturation, and antimicrobial tolerance, under both static and flow conditions. S. aureus biofilms were established and assessed using quantitative (viable bacterial load and minimal biofilm eradication concentration [MBEC]) and qualitative (scanning electron microscopy) endpoints. Both PLA and PETG supported biofilm formation across models; however, PLA tended to show higher early adhesion and greater biofilm density. In static assays, PLA demonstrated higher CFU values than PETG, whereas vancomycin MBEC values were similar between materials. Assay-dependent differences in MBEC were observed across platforms, underscoring how model structure can influence apparent antimicrobial susceptibility. Under dynamic flow, biofilm burden increased relative to static conditions, with minimal material-dependent differences. Collectively, these results highlight the susceptibility of both polymers to biofilm formation and demonstrate the value of a multi-model framework for evaluating material-associated biofilm behavior and benchmarking antimicrobial performance on 3D-printed device-relevant substrates.
Traditional yogurt cannot be directly 3D printed into shape. This study uses hydroxypropyl distarch phosphate (HPDSP) at varying gelatinization degrees (GDs) to enhance yogurt's 3D printability. By using the gelatinization curve model of HPDSP, the 3D printing forming effects of yogurt ink with varying gelatinization degrees were investigated, and forming mechanism was explored based on rheological properties, microstructure, infrared spectroscopy, fluorescence spectroscopy, and intermolecular interactions. Sensory quality and lactic acid bacteria count were analyzed. The results showed that increasing HPDSP gelatinization degree (G50-G100) elevated the apparent viscosity and storage modulus (G') of the yogurt ink, improving 3D printing accuracy (overall printing deviation rate [OPD] decreased from 69.1% to 0.56%). Printing outcomes were optimal at G80-G100 (p > 0.05). The molecular structure of HPDSP transitioned from an ordered arrangement to a disordered state or short-range ordered structure, interacting with milk proteins through hydrogen bonds and electrostatic interactions to form a denser, more uniform gel network structure, enhancing the self-supporting capability of the 3D-printed products. G80 (processed at 59.6°C) demonstrated optimal printing precision (OPD = 0.93%), sensory acceptability (89 points), and lactic acid bacteria count (LAB count: 8.09 log CFU g-1), making it the preferred formulation for 3D-printed yogurt. This study expands options for personalized customization in 3D-printed yogurt production. PRACTICAL APPLICATIONS: This study proposes a simplified method for 3D printing yogurt by adding HPDSP and regulating its gelatinization degree. This technology can create products with different patterns and textures by utilizing a small amount of yogurt, thereby diversifying the product range and enabling efficient use of materials. With its straightforward formulation and operation, this approach innovates dietary experiences and improves market competitiveness in on-site personalized yogurt customization and foods surface decoration.
Direct Metal Printing (DMP) three-dimensional (3D) printing technology, also known as direct laser sintering of metal powders, enables the production of metal components with complex geometries that are not achievable with traditional casting methods or subtractive techniques. The DMP method enables the production of metal objects with high precision. One of the important applications of additive manufacturing is the production of medical implants. A significant challenge in the production of medical devices using DMP technology is the so-called post-processing. An improperly performed postproduction cleaning process may lead to the presence of metal powder particles that were not bound during laser melting. Their presence in the friction pair after implantation, and/or their release into surrounding tissues, may cause accelerated wear and induce inflammatory reactions. The most common drawbacks of widely available and commonly used post-processing methods include their limited effectiveness in removing surface powder residues and a significant loss in volume and mass of the prints. In the second case, the result is a reduction in the mechanical strength of the implant (e.g., with electrochemical methods), and in the first case, there is a risk of inducing an immune response in the body. According to literature reports, regardless of size, at high concentrations in the body (1 × 106 particles/mL), unbound powder particles induce an immune response already at an early stage. Electrochemical methods effectively remove unbound particles, but at the same time cause significant losses in the volume and mass of prints, which affects their strength. This study aimed to improve the quality of 3D-printed implants by cleaning their surfaces of unbound metal particles (post-processing). Comparing the results reported in the literature for various surface treatment methods (chemical, electrochemical, mechanical, plasma), plasma treatment was identified as the most promising solution. Oxygen and argon plasma cleaning was performed at different time periods (1, 2, and 4 h) on sandblasted substrates after production and without this treatment. The study aimed to verify the effectiveness of the plasma cleaning process in removing particles from metallic 3D-printed components and to assess the impact of surface treatments on biological response using an osteoblast cell model.
Microneedles (MNs) have progressed to a potentially viable method of transdermal vaccination and have accrued immense attention in recent years. By overcoming first-pass metabolism, this emerging technology elicits efficacious therapeutic effects and improved patient compliance. Various technologies and material compositions have been explored to enable drug delivery including solid, coated, dissolving, hollow and hydrogel-forming MNs. In progressive science, there are several emerging engineering techniques that have been used to fabricate MNs for use in drug delivery and aligning therapies, including (not limited to) micromoulding, 3D printing, aerosol jet printing and various electrohydrodynamic strategies. These explorations have yielded promising outcomes in terms of facile MN manufacturing, processing, enhanced mechanical features, applicability (self-administered), portability and therapeutic efficiency. More recently, emerging engineering aspects (e.g. 3D printing, various laser-based techniques and electrospray technology) have been adapted to develop MN vaccine platforms or demonstrate potential in this remit, adding to more established MN vaccine engineering platforms (e.g. micrmoulding). Such developments are viewed as crucial; firstly, to eliminate/reduce the spread of infection as the emergence and occurrence of outbreaks increase, and secondly, to limit the strain on national healthcare systems which rely heavily upon assisted vaccine administration. This review focuses on selected, up-to-date developments and progression of engineering MN technologies/devices into MN vaccine therapeutic platforms. It also embraces specific examples, highlighting applicability and adaptability of existing technologies, with current advances shown and future scope highlighted.
Purpose: To compare the monomer leaching of 3D-printed denture base materials (NextDent® Denture 3D+ [D3D]) and orthodontic base material (NextDent® Ortho Flex [OF]) with conventional poly-methyl methacrylate (PMMA) resins at 5 time points. Methods: Fifteen standardized samples (N=5 /group) of D3D, OF, and PMMA materials were submerged in artificial saliva for 48 hours. The solutions were extracted, and the monomer release rate and amount were measured using high-performance liquid chromatography (HPLC) at 0, 8, 16, 24, and 48 hours. One-way analysis of variance, independent t-tests, and post-hoc least significant difference tests were used to compare monomer release rates and amounts across different time intervals and materials. Results: Methyl methacrylate was detected in the PMMA group at 0.0034 wt%, which is below the ISO threshold (<4.5 wt%). Significant differences were observed in monomer release rates and patterns among the groups (P<0.001). The highest monomer release occurred within the first 8 hours and decreased drastically over time (P<0.001). Among 3D printing groups, the OF group exhibited a higher release rate than the D3D group at all time points (0, 8, 16, 24, and 48 hours; P <0.001). The D3D group maintained a consistently low release rate. Conclusions: The levels of monomer release in this in vitro study would be considered safe for use in pediatric dentistry. Due to the highest monomer release occurring within the first 8 hours, it is recommended that appliances be delivered at least 8 hours after fabrication to minimize initial exposure.