Encapsulation of ß-carotene in gelatin-gum Arabic-sodium carboxymethylcellulose complex coacervates: Enhancing surimi gel properties and exploring 3D printing potential.

This study investigates the utilization of functional additives (ß-carotene microcapsules) and 3D printing technology for the production of innovative surimi products. The ß-carotene microcapsules were prepared using different ratios of gelatin (Ge), gum Arabic (Ara), and carboxymethylcellulose sodium (CMC). Among these ratios, the ratio of 5:5:1 (Ge:Ara:CMC) resulted in more stable microcapsules spherical structures and better environmental stability. Subsequently, different concentrations (5-20 %) of the obtained ß-carotene microcapsules were added to surimi samples. As the concentration increased, there was an improvement in the gel strength of the surimi. However, no significant changes were observed when the concentration was 15 % (p > 0.05). All samples exhibited shear thinning behavior. The addition of microcapsules improved the resilience and thixotropy of surimi, making it more suitable for 3D printing applications. The inclusion of ß-carotene microcapsules in surimi products not only meets the nutritional needs of consumers, but also provides valuable insights for the development of functional surimi products.

Design, fabrication, and evaluation of single- and multi-level 3D-printed non-covering cervical spinal fusion surgery templates.

Background: Cervical spinal fusion surgeries require accurate placement of the pedicle screws. Any misplacement/misalignment of these screws may lead to injuries to the spinal cord, arteries and other organs. Template guides have emerged as accurate and cost-effective tools for the safe and rapid insertions of pedicle screws. Questions/Purposes: Novel patient-specific single- and multi-level non-covering templates for cervical pedicle screw insertions were designed, 3D-printed, and evaluated. Methods: CT scans of two patients were acquired to reconstruct their 3D spine model. Two sets of single-level (C3-C7) and multi-level (C4-C6) templates were designed and 3D-printed. Pedicle screws were inserted into the 3D-printed vertebrae by free-hand and guided techniques. For single-level templates, a total of 40 screws (2 patients × 5 vertebrae × 2 methods × 2 screws) and for multi-level templates 24 screws (2 patients × 3 vertebrae × 2 methods × 2 screws) were inserted by an experienced surgeon. Postoperative CT images were acquired to measure the errors of the entry point, 3D angle, as well as axial and sagittal plane angles of the inserted screws as compared to the initial pre-surgery designs. Accuracy of free-hand and guided screw insertions, as well as those of the single- and multi-level guides, were also compared using paired t-tests. Results: Despite the minimal removal of soft tissues, the 3D-printed templates had acceptable stability on the vertebrae during drillings and their utilization led to statistically significant reductions in all error variables. The mean error of entry point decreased from 3.02 mm (free-hand) to 0.29 mm (guided) using the single-level templates and from 5.7 mm to 0.76 mm using the multi-level templates. The percentage reduction in mean of other error variables for, respectively, single- and multi-level templates were as follows: axial plane angle: 72% and 87%, sagittal plane angle: 56% and 78%, and 3D angle: 67% and 83%. The error variables for the multi-level templates generally exceeded those of the single-level templates. The use of single- and multi-level templates also considerably reduced the duration of pedicle screw placements. Conclusion: The novel single- and multi-level non-covering templates are valuable tools for the accurate placement of cervical pedicle screws.

Localized delivery of metformin via 3D printed GelMA-Nanoclay hydrogel scaffold for enhanced treatment of diabetic bone defects.

Background: Diabetic bone defects present significant challenges for individuals with diabetes. While metformin has been explored for bone regeneration via local delivery, its application in treating diabetic bone defects remains under-explored. In this study, we aim to leverage 3D printing technology to fabricate a GelMA-Nanoclay hydrogel scaffold loaded with metformin specifically for this purpose. The objective is to assess whether the in situ release of metformin can effectively enhance osteogenesis, angiogenesis, and immunomodulation in the context of diabetic bone defects. Materials and methods: Utilizing 3D printing technology, we constructed a GelMA-Nanoclay-Metformin hydrogel scaffold with optimal physical properties and biocompatibility. The osteogenic, angiogenic, and immunomodulatory characteristics of the hydrogel scaffold were thoroughly investigated through both in vitro and in vivo experiments. Results: GelMA10%-Nanoclay8%-Metformin5mg/mL was selected as the bioink for 3D printing due to its favorable swelling rate, degradation rate, mechanical strength, and drug release rate. Through in vitro investigations, the hydrogel scaffold extract, enriched with metformin, demonstrated a substantial enhancement in the proliferation and migration of BMSCs within a high-glucose microenvironment. It effectively enhances osteogenesis, angiogenesis, and immunomodulation. In vivo experimental outcomes further underscored the efficacy of the metformin-loaded GelMA-Nanoclay hydrogel scaffold in promoting superior bone regeneration within diabetic bone defects. Conclusions: In conclusion, while previous studies have explored local delivery of metformin for bone regeneration, our research is pioneering in its application to diabetic bone defects using a 3D printed GelMA-Nanoclay hydrogel scaffold. This localized delivery approach demonstrates significant potential for enhancing bone regeneration in diabetic patients, offering a novel approach for treating diabetic bone defects. The translational potential of this article: Our study demonstrates, for the first time, the successful loading of the systemic antidiabetic drug metformin onto a hydrogel scaffold for localized delivery. This approach exhibits significant efficacy in mending diabetic bone defects, presenting a promising new avenue for the treatment of such conditions.

The Open SprayBot: A high-throughput paper spray mass spectrometry platform for disease screening.

Newborn disease screening increases survival, improves quality of life and reduces treatment costs for healthcare systems. Mass spectrometry (MS) is an effective method for metabolic screening. However, conventional analytical methods require biofluid handling and cooling conditions during transport, making the logistics difficult and expensive, especially for remote regions. 'Paper-spray' (PS) ionization generates a charged solvent spray from samples deposited on paper strips. Therefore, samples can be applied on a suitable matrix and shipped as dried spots to diagnostic laboratories with standard postal or messenger services. We built a robotic platform, the 'Open SprayBot', to automatically analyze paper-deposited samples via PS-MS and increase the sample throughput. The system is operated via RUMBA32 and Arduino Mega boards. A commercial syringe pump and power supply provide solvent application and electrical current required for PS-MS. The usability of the Open SprayBot was demonstrated by quantifying palmitoyl-l-carnitine, a common biomarker in newborn screening.

Trends and future perspectives of 3D printing in prosthodontics.

The three-dimensional (3D) printing technology has led to transformative shift in prosthodontics. This review summarizes the evolution, processing techniques, materials, integration of digital plan, challenges, clinical applications and future directions of 3D printing in prosthodontics. It appraises from the launch of 3D printing to its current applications in prosthodontics. The convergence of printing technology with digital dentistry has facilitated the creation of accurate, customized prostheses, redefining treatment planning, design, and manufacturing processes. The progression of this technology is from generating models to prosthesis like-fixed dental prosthesis (FDP), implants, and splints. Additionally, it exhibits more wide capabilities. The exploration of materials for 3D printing provides various options like polymers, ceramics, metals, and hybrids, each with distinctive properties that are applicable to different clinical scenarios. The combination of 3D-printing technology and digital workflow simplifies the processes of data transfer, computer-aided design (CAD) design to fabrication, decreasing errors and chairside time. The clinical benefits include enhanced accuracy, comfort, conservative lab procedures, and economics. Challenges in the technology involve significant aspects like initial investment, material availability, and skill requirements. Future trends emphasize on research for improved materials, bioprinting integration, artificial intelligence (AI) application, regularization efforts to ensure safe and common use of the technology. 3D printing offers promise in prosthodontics, addressing challenges through research. The material improvements will promote its broader adoption and revolutionize the future of dental rehabilitation.

Novel 3D printed TPMS scaffolds: microstructure, characteristics and applications in bone regeneration.

Bone defect disease seriously endangers human health and affects beauty and function. In the past five years, the three dimension (3D) printed radially graded triply periodic minimal surface (TPMS) porous scaffold has become a new solution for repairing bone defects. This review discusses 3D printing technologies and applications for TPMS scaffolds. To this end, the microstructural effects of 3D printed TPMS scaffolds on bone regeneration were reviewed and the structural characteristics of TPMS, which can promote bone regeneration, were introduced. Finally, the challenges and prospects of using TPMS scaffolds to treat bone defects were presented. This review is expected to stimulate the interest of bone tissue engineers in radially graded TPMS scaffolds and provide a reliable solution for the clinical treatment of personalised bone defects.

Bridging the Gap: Integrating 3D Bioprinting and Microfluidics for Advanced Multi-Organ Models in Biomedical Research.

Recent advancements in 3D bioprinting and microfluidic lab-on-chip systems offer promising solutions to the limitations of traditional animal models in biomedical research. Three-dimensional bioprinting enables the creation of complex, patient-specific tissue models that mimic human physiology more accurately than animal models. These 3D bioprinted tissues, when integrated with microfluidic systems, can replicate the dynamic environment of the human body, allowing for the development of multi-organ models. This integration facilitates more precise drug screening and personalized therapy development by simulating interactions between different organ systems. Such innovations not only improve predictive accuracy but also address ethical concerns associated with animal testing, aligning with the three Rs principle. Future directions include enhancing bioprinting resolution, developing advanced bioinks, and incorporating AI for optimized system design. These technologies hold the potential to revolutionize drug development, regenerative medicine, and disease modeling, leading to more effective, personalized, and humane treatments.

Emerging Biomedical and Clinical Applications of 3D-Printed Poly(Lactic Acid)-Based Devices and Delivery Systems.

Poly(lactic acid) (PLA) is widely used in the field of medicine due to its biocompatibility, versatility, and cost-effectiveness. Three-dimensional (3D) printing or the systematic deposition of PLA in layers has enabled the fabrication of customized scaffolds for various biomedical and clinical applications. In tissue engineering and regenerative medicine, 3D-printed PLA has been mostly used to generate bone tissue scaffolds, typically in combination with different polymers and ceramics. PLA's versatility has also allowed the development of drug-eluting constructs for the controlled release of various agents, such as antibiotics, antivirals, anti-hypertensives, chemotherapeutics, hormones, and vitamins. Additionally, 3D-printed PLA has recently been used to develop diagnostic electrodes, prostheses, orthoses, surgical instruments, and radiotherapy devices. PLA has provided a cost-effective, accessible, and safer means of improving patient care through surgical and dosimetry guides, as well as enhancing medical education through training models and simulators. Overall, the widespread use of 3D-printed PLA in biomedical and clinical settings is expected to persistently stimulate biomedical innovation and revolutionize patient care and healthcare delivery.

Three-Dimensionally Printed Agarose Micromold Supports Scaffold-Free Mouse Ex Vivo Follicle Growth, Ovulation, and Luteinization.

Ex vivo follicle growth is an essential tool, enabling interrogation of folliculogenesis, ovulation, and luteinization. Though significant advancements have been made, existing follicle culture strategies can be technically challenging and laborious. In this study, we advanced the field through development of a custom agarose micromold, which enables scaffold-free follicle culture. We established an accessible and economical manufacturing method using 3D printing and silicone molding that generates biocompatible hydrogel molds without the risk of cytotoxicity from leachates. Each mold supports simultaneous culture of multiple multilayer secondary follicles in a single focal plane, allowing for constant timelapse monitoring and automated analysis. Mouse follicles cultured using this novel system exhibit significantly improved growth and ovulation outcomes with comparable survival, oocyte maturation, and hormone production profiles as established three-dimensional encapsulated in vitro follicle growth (eIVFG) systems. Additionally, follicles recapitulated aspects of in vivo ovulation physiology with respect to their architecture and spatial polarization, which has not been observed in eIVFG systems. This system offers simplicity, scalability, integration with morphokinetic analyses of follicle growth and ovulation, and compatibility with existing microphysiological platforms. This culture strategy has implications for fundamental follicle biology, fertility preservation strategies, reproductive toxicology, and contraceptive drug discovery.

Investigation of Degradation and Biocompatibility of Indirect 3D-Printed Bile Duct Stents.

This study proposes a bile duct stent based on indirect 3D printing technology. Four ratio materials were synthesized from lactic acid (LA) and glycolide (GA) monomers by melt polymerization: PLA, PLGA (70:30), PLGA (50:50), and PLGA (30:70). The four kinds of material powders were preliminarily degraded, and the appearance was observed with an optical microscope (OM) and a camera. The weight and appearance of the four materials changed significantly after four weeks of degradation, which met the conditions for materials to be degraded within 4-6 weeks. Among them, PLGA (50:50) lost the most-the weight dropped to 13.4%. A stent with an outer diameter of 10 mm and an inner diameter of 8 mm was successfully manufactured by indirect 3D printing technology, demonstrating the potential of our research. Then, the degradation experiment was carried out on a cylindrical stent with a diameter of 6 mm and a height of 3 mm. The weight loss of the sample was less than that of the powder degradation, and the weight loss of PLGA (50:50) was the largest-the weight dropped to 79.6%. The nano-indenter system measured the mechanical properties of materials. Finally, human liver cancer cells Hep-3B were used to conduct in vitro cytotoxicity tests on the scaffolds to test the biocompatibility of the materials. A bile duct stent meeting commercial size requirements has been developed, instilling confidence in the potential of our research for future medical applications.

Three-Dimensional-Printed Modular Titanium Alloy Plates for Osteosynthesis of the Jawbone.

BACKGROUNDS: The titanium-aluminum-vanadium alloy (Ti-6Al-4V) is frequently used in implantology due to its biocompatibility. The use of 3D printing enables the mechanical modification of implant structures and the adaptation of their shape to the specific needs of individual patients. METHODS: The titanium alloy plates were designed using the 3D CAD method and printed using a 3D SLM printer. Qualitative tests were performed on the material surface using a microcomputed tomography scanner. The cytotoxicity of the modular titanium plates was investigated using the MTT assay on the L929 cell line and in direct contact with Balb/3T3 cells. Cell adhesion to the material surface was evaluated with hFOB1.19 human osteoblasts. Microbial biofilm formation was investigated on strains of Lactobacillus rhamnosus, Staphylococcus epidermidis, Streptococcus mutans and Candida albicans using the TTC test and scanning electron microscopy (SEM). RESULTS: The surface analysis showed the hydrophobic nature of the implant. The study showed that the titanium plates had no cytotoxic properties. In addition, the material surface showed favorable properties for osteoblast adhesion. Among the microorganisms tested, the strains of S. mutans and S. epidermidis showed the highest adhesion capacity to the plate surface, while the fungus C. albicans showed the lowest adhesion capacity. CONCLUSIONS: The manufactured modular plates have properties that are advantageous for the implantation and reduction in selected forms of microbial biofilm. Three-dimensional-printed modular titanium plates were investigated in this study and revealed the potential clinical application of this type of materials, regarding lack of cytotoxicity, high adhesion properties for osteoblasts and reduction in biofilm formation. The 3D CAD method allows us to personalise the shape of implants for individual patients.

Evaluating the value of individualized 3D printed models for examination, diagnosis and treatment planning of cervical cancer.

BACKGROUND: 3D printing holds great potential of improving examination, diagnosis and treatment planning as well as interprofessional communication in the field of gynecological oncology. In the current manuscript we evaluated five individualized, patient-specific models of cervical cancer FIGO Stage I-III, created with 3D printing, concerning their value for translational oncology. METHODS: Magnetic resonance imaging (MRI) of the pelvis was performed on a 3.0 Tesla MRI, including a T2-weighted isotropic 3D sequence. The MRI images were segmented and transferred to virtual 3D models via a custom-built 3D-model generation pipeline and printed by material extrusion. The 3D models were evaluated by all medical specialties involved in patient care of cervical cancer, namely surgeons, radiologists, pathologists and radiation oncologists. Information was obtained from evaluated profession-specific questionnaires which were filled out after inspecting all five models. The questionnaires included multiple-select questions, questions based on Likert scales (1 = "strongly disagree " or "not at all useful " up to 5 = "strongly agree " or "extremely useful ") and dichotomous questions ("Yes" or "No"). RESULTS: Surgeons rated the models as useful during surgery (4.0 out of 5) and for patient communication (4.7 out of 5). Furthermore, they believed that the models had the potential to revise the patients' treatment plan (3.7 out of 5). Pathologists evaluated with mean ratings of 3.0 out of 5 for the usefulness of the models in diagnostic reporting and macroscopic evaluation. Radiologist acknowledged the possibility of providing additional information compared to imaging alone (3.7 out of 5). Radiation oncologists strongly supported the concept by rating the models highly for understanding patient-specific pathological characteristics (4.3 out of 5), assisting interprofessional communication (mean 4.3 out of 5) and communication with patients (4.7 out of 5). They also found the models useful for improving radiotherapy treatment planning (4.3 out of 5). CONCLUSION: The study revealed that the 3D printed models were generally well-received by all medical disciplines, with radiation oncologists showing particularly strong support. Addressing the concerns and tailoring the use of 3D models to the specific needs of each medical speciality will be essential for realizing their full potential in clinical practice.

Modulable 3D-printed plantibody-laden platform enabling microscale affinity extraction and ratiometric front-face fluorescence detection of microcystin-LR in marine waters.

A 3D-printed stereolithographic platform for selective biorecognition is designed to enable convective microscale affinity extraction of microcystin-LR (MC-LR) followed by direct solid-phase optosensing exploiting ratiometric front-face fluorescence spectroscopy. For this purpose, a recombinant monoclonal plantibody (recAb) is covalently attached to a 3D-printed structure for sorptive immunoextraction, whereupon the free and unbound primary amino moieties of the recAb are derivatized with a fluorescent probe. The fluorophore-recAb-MC-LR laden device is then accommodated in the cuvette holder of a conventional fluorometer without any instrumental modification for the recording of the solid-phase fluorescence emission. Using Rodbard's four-parameter sigmoidal function, the 3D-printed bioselective platform features a limit of detection (LOD) of 28 ng L-1 using a sample volume of 500 mL, device-to-device reproducibility down to 12%, and relative recoveries ranging from 91 to 100% in marine waters. Printed prototypes are affordable, just 0.4 € per print and ≤ 10 € per device containing recAb. One of the main assets of the miniaturized immunoextraction device is that it performs comparably well in terms of analytical figures of merit with costly mass spectrometric-based analytical methodologies, such as HPLC-MS/MS. The device is readily applicable to high-matrix samples, such as seawater, as opposed to previous biosensing platforms, just applied to freshwater systems.

Utility of 3D-printed vascular modeling in microsurgical breast reconstruction: a systematic review.

BACKGROUND: Microsurgical breast reconstruction presents a technical challenge in preoperative planning and flap harvest. Given the limitations of computed tomographic angiography as a preoperative aid, 3D printing has emerged as an avenue for creating patient-specific anatomical models for pre- and intraoperative use. This systematic review assesses the current use and utility of 3D-printed vascular models (3DVMs) in microsurgical breast reconstruction. METHODS: MEDLINE, Embase, and CENTRAL were searched for English articles published from 1946 to 2024. Studies utilizing 3D-printed vascular modeling in the context of microsurgical breast reconstruction were included if they reported surgical, model-, or user-related outcomes. The Newcastle-Ottawa Scale and Joanna Briggs Institute checklists were used for quality assessment. Results were reported according to PRISMA guidelines. RESULTS: Six hundred and nineteen records were retrieved. Following specific inclusion and exclusion criteria, 29 studies underwent full-text review. Eight studies totaling 181 patients and 261 flaps were included in the final analysis. 3DVMs were used to model deep inferior epigastric perforator (DIEP) and muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM) flap perforator origin, course, distribution, and surrounding anatomy. They were used for perforator selection, flap harvest, and training. Use of 3DVMs reduced harvest time by up to 23 min per case. No complications or preoperative plan deviations were reported in 3DVM-guided cases. Surgeons endorsed significant model utility in anatomical visualization, preoperative planning, and flap harvest. Model cost, production time, and adoption were identified as barriers to use. CONCLUSIONS: 3DVMs can enhance preoperative planning, intraoperative decision-making, and operative efficiency in unilateral DIEP and bilateral MS-TRAM flap breast reconstructions.

Enhancing biofilm resistance and preserving optical translucency of 3D printed clear aligners through carboxybetaine-copolymer surface treatment.

OBJECTIVES: This study aimed to use a carboxybetaine methacrylate (CBMA) copolymer solution to surface treat 3D printed clear aligners at different fabrication stages, to impart antifouling properties, and assess the surface treatment at various fabrication stages' impact on physico-mechanical characteristics. METHODS: Surface treatments using a blend of 2-hydroxyethyl methacrylate (HEMA) and CBMA, termed CCS, were performed at various stages of 3D printed clear aligner fabrication. Experimental groups, CB1, CB2, and CB3, were determined by the stage of surface treatment during post-processing. CB1, CB2, and CB3 received treatment before post-curing, after post-curing, and after post-processing, respectively. Untreated samples served as controls. Physical and mechanical properties were assessed through tensile testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and UV-Vis spectroscopy. The surface was further characterized through scanning electron microscopy and contact angle measurements. The cytotoxicity was assessed with 7-day elution and agar diffusion assays. Lastly, bacterial biofilm resistance was evaluated using confocal laser scanning microscopy. Crystal violet assay was performed using Streptococcus mutans. RESULTS: Surface treatment during CB1 stage exerted the most significantly unfavorable influence on properties of the 3D printed aligner resin. CB2 samples showed the maximum preservation of translucency even after 7-day aging. CB2 and CB3 phases showed enhanced hydrophilicity of sample surfaces with reduced adhesion of multispecies biofilm and S. mutans. SIGNIFICANCE: Application of CCS surface treatment immediately after post-curing (CB2) can enhance the biofilm resistance of 3D printed clear aligners while maintaining high fidelity to optical translucency and constituent mechanical properties.

Evaluation of fracture resistance and marginal fit of implant-supported interim crowns fabricated by conventional, additive and subtractive methods.

BACKGROUND: Interim crowns are utilized for restoring implants during and after the process of osseointegration. However, studies on adaptation and fracture strength of implant-supported interim crowns are rare. AIM OF THE STUDY: The aim of this in vitro study is evaluating marginal fit and fracture resistance of conventional, subtractive, and additive methods of fabricating implant-supported interim crowns. MATERIALS AND METHODS: An implant was placed in an epoxy resin model with a missing first molar. A scan body was attached, and scanned with an intraoral scanner (IOS), the STL file was used to fabricate eighteen master models with standardized implant digital analogue spaces. The digital analogues and their corresponding abutments were attached to the master models and scanned with the IOS, the STL files were used to fabricate eighteen crowns using three different techniques (n = 6): conventional (CR); from Autopolymerizing composite resin, subtractive (SM); milled from PMMA resin blanks, and additive (AM); from 3D printed resin material. The crowns were fitted and cemented on their corresponding abutments and subjected to cyclic loading and thermocycling. The marginal fit was evaluated using a stereomicroscope. The crowns were then loaded until fractured in a universal testing machine. The Shapiro-Wilk and the Kolmogorov-Smirnov tests revealed that data of Marginal gap was non-parametric. Kruskal-Wallis test followed by the Dunn test was used (α = 0.05). While data of Fracture resistance test was parametric. ANOVA (F-test) was used followed by the Tukey test (α = 0.05). RESULTS: For marginal gap, a significant difference was shown between the study groups (P = .001) according to Kruskal-Wallis test. Groups SM and AM had significantly lower marginal gap values compared to group CR (P = .003). No significant difference was found between groups SM and AM (P = .994). For fracture resistance, One-way ANOVA revealed a significant difference in fracture resistance between study groups (P < .001). Group SM had significantly higher fracture strength followed by group AM and group CR (P = .001). CONCLUSIONS: Group SM and AM showed better marginal adaptation than group CR. Group SM showed superior fracture resistance compared to other groups. All study groups showed acceptable marginal gap and fracture resistance.

Development of a novel percutaneous digital flexible nephroscope: its use and application.

BACKGROUND: Renal calculi are one of the most frequent diseases in urology, and percutaneous nephrolithotomy (PCNL) being the gold standard for treating renal calculi larger than 2 cm. However, traditional rigid nephroscope cannot bend, presents significant limitations during PCNL. This study aims to develop a novel digital flexible nephroscope for PCNL and verify its safety and efficacy using 3D printed models and ex vivo porcine kidney models, providing new equipment for PCNL. METHODS: Based on the determined technical parameters, the novel digital flexible nephroscope was manufactured. First, 3D-printed model and ex vivo porcine kidney models were utilized to simulate the PCNL procedures. Then, the traditional rigid nephroscope and the novel digital flexible nephroscope were utilized to simulate the PCNL procedures on 10 ex vivo porcine kidneys for comparison. We observed and recorded the renal calyces visualized and accessed by both the traditional rigid nephroscope and the novel digital flexible nephroscope. RESULTS: In both the 3D printing and ex vivo porcine kidney models, the novel percutaneous digital flexible nephroscope smoothly entered the renal collecting system through the percutaneous renal tract. It freely changed angles to reach most target calyces, demonstrating significant advantages over the traditional rigid nephroscope. CONCLUSION: The successful development of the novel percutaneous digital flexible nephroscope allows it to be used either independently or as an adjunct in complex stone cases, providing more effective and safer surgical equipment for percutaneous nephrolithotomy.

Dimensional changes over time in stereolithographic models fabricated with a 3D printer.

This study aimed to ascertain the effects of the shape of stereolithographic models fabricated with a three-dimensional (3D) printer and the use of different types of liquid resin on the dimensional changes of these models over time, to obtain valuable information for determining the period for which such models can be used following fabrication. Stereolithography models with the shape of a large truncated cone or a small truncated cone were fabricated using liquid resin as surgical guides (Group G) or master casts (Group M). (four groups in total, each n = 11). The shapes of all experimental specimens were measured immediately after fabrication and 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks, 2 months, 3 months, 6 months, 1 year, and 1.5 years later. The shape data collected immediately after fabrication were taken as baseline data, and the dimensional changes over time at each timepoint were calculated. No significant change from 1 day to 1 year after fabrication was observed in any of the groups, but the change after 1.5 years was significantly larger than the changes at the other timepoints (p < 0.001). Significantly larger changes were evident in Group M than in Group G at all timepoints (p < 0.001). These results suggested that, from the viewpoint of dimensional stability over time, stereolithographic models should be used within 1 year of fabrication, and that the type of liquid resin used for stereolithographic model fabrication may affect how its dimensions change over time.

Valorization of Fruit and Vegetables Industry By-Streams for 3D Printing-A Review.

An energy supply crisis is impacting all the branches, including the agriculture and food industry. The wise and responsible utilization of plant raw materials already cultivated is becoming a must in the country's economy. Not only the waste of the resources included but also the environmental challenge are concerns behind the not exploited food production by-streams and leftovers' valorization. Fruits and vegetables' out of the market quality "beauty" standards are still valuable sources of nutritious compounds. The conversion of raw materials into edible products can be provided by many techniques, with three-dimensional printing being the most individualized one. The main objective of this review was to summarize the existing efforts for the valorization of fruits and vegetable residuals into edible 3D inks and then 3D printed products. The clustering analysis was used for the separation of certain research approaches in fruit and vegetable wastes exploitation for 3D printing inks' formulation. As the multilayer deposit technique is strongly dependent on the printing conditions and 3D ink formulation, therefore the tabularized description was included presenting the nozzle diameter, printing speed and other conditions specified.

Conformity of Three Pre-Contoured Clavicular Plates Compared Using Personalized 3D-Printed Models of Clavicles from Patients.

The human clavicle's unique S-shaped, three-dimensional structure complicates fracture management. This study evaluated the anatomical conformity of pre-contoured anatomical plates using 3D-printed clavicle models. CT scans from 30 patients (15 males and 15 females) were used to create these models. Three brands of distal clavicle plate systems (Acumed, Synthes, and Arthrex) were tested for fit. Measurements included the distance from the distal end of the clavicle to the plate's lateral end, the gap between the clavicle and the plate, and the overhang distance. Results showed significant differences in clavicle length between sexes, with men having a mean length of 156.1 ± 7.6 mm and women 138.4 ± 4.3 mm, both with normal distribution (p > 0.05). The mean lateral distance was 7.9 ± 1.7 mm, and the mean medial gap was 3.6 ± 3.0 mm, showing no significant differences between products or sexes. The mean overhang distance was 5.8 ± 4.6 mm, with larger values in women for the Acumed (p = 0.037) and Arthrex (p = 0.000) plates. Overall, pre-contoured plates exhibited notable discrepancies, especially in shorter clavicles.