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Enzymatic biocatalysis typically generates less waste, uses less water, and minimizes energy consumption compared to traditional chemical methods. Efficient, cell-free biosynthesis relies on the reuse of its valuable biocatalysts. Immobilization of enzymes on solid supports, such as enzyme carrier resins (ECRs), offers a reliable and widely deployed approach to maximize enzyme turnover in cell-free biosynthesis. We focus on two major bottlenecks associated with optimizing cell-free biocatalysis. First, we apply our lab's 3D-printed labware to screen ECRs in 96-well mini-reactors to optimize enzyme immobilization conditions. Second, we introduce inline infrared spectroscopy to monitor bioreactor output and maximize enzyme productivity. Urease provides a model system for examining immobilization conditions and continuous assessment of biocatalyst performance. As required for the high substrate concentrations to improve process efficiency and minimize waste, urease was studied in unusually high concentrations of its substrate – molar concentrations of urea. The optimized reactor processed 3.24 L of 4.00 M urea at an average volumetric productivity of 13 g ⋅ L−1 ⋅ h−1 over 18 h and achieved an estimated productivity number of >17.4 kg urea processed per g of immobilized urease Type-IX. This workflow can be generalized to most biocatalytic processes and could accelerate adoption of cell-free biosynthesis for greater chemical sustainability.

Purpose: To evaluate the dimensional stability over time of additively manufactured surgical templates, fabricated by different resins, and stored by different methods. Materials and Methods: Using a 3D printer with DLS technology and two different resins (Surgical Guide (SG)‐WhipMix and Key Guide (KG)‐KeystoneIndustries), 96 surgical guides were additively manufactured. The guides were stored in three different environments: directly exposed to sunlight (S1), in normal interior room conditions (S2), and in darkness (S3). The guides were digitally scanned immediately after fabrication and post‐processing, and after 1, 3, and 6 months of storage. For each group, the mean deviation of the root mean square (RMS) between guide's intaglio surface, as well as the axial deviation between sleeves' housings were calculated. Results: The mean axial variations of angular axis deviation of sleeves' housings ranged between 0.09° and 3.99°. The mean deviation of the RMS discrepancy in guide's intaglio ranged from 0.1 to 0.18 mm. Variations were significant (p < 0.001) only for the S1 group and only for SG material. After 3 months, an additional storage time of 3 months did not have any further effect on dimensional stability. Conclusions: Within the limitations of the present study, storage time of a surgical guide for up to 3 months after manufacturing, as well as printing material can significantly affect surgical guide's dimensional stability, when they are exposed to direct or indirect sunlight conditions. Storage of guides in a dark environment is recommended in order to avoid an additional source of error in computer‐guided surgery workflows. [ABSTRACT FROM AUTHOR]

Objective: The primary research aim was to determine if the use of traditional or 3D printed prosthesis resulted in better functional outcome scores in hip arthroplasty. Methods: A systematic review and meta-analysis was conducted utilizing the PRISMA 2020 guidelines. Six databases (PubMed, Embase, Scopus, WebOfScience, and Cochrane Library, Google Scholar) were searched yielding 1117 article titles and abstracts. Rayyan.ai was used to detect duplicates (n = 246) and for manual screening for inclusion and exclusion criteria. Included were controlled studies of any publication time that assessed Harris Hip Score (HHS) at baseline and twelve months. Six papers were sought for full text review of which three studies totaling 195 hips met final inclusion. Results: Mean HHS in the control group went from 38.15 (± 6.02) at baseline to 80.30 (± 4.79) at twelve months follow-up, while the 3D group saw a change from 37.81 (± 5.84) to 90.60 (± 4.49). Significant and large improvements between time points were seen within the control group [p =.02, Cohen’s d = 8.57 (1.48, 15.56)] and 3D group [p < 0.01, Cohen’s d = 9.18 (3.50, 14.86)]. The HHS score of the 3D group improved by 10.64 points more than the HHS score of the control group, which is a statistically insignificant (p = 0.89) amount. Conclusion: Group differences in pooled mean HHS scores at twelve months follow-up surpassed established minimum differences for clinical importance. High quality research should be further pursued to elucidate these findings. [ABSTRACT FROM AUTHOR]

The scaphoid bone is essential for wrist stability, force transmission, and movement, being crucial for maintaining carpal kinematics. In cases where the scaphoid is non-reconstructable, a complete replacement can serve as a treatment option to preserve carpal alignment and motion. This approach has evolved since its first descriptions in 1945, benefiting significantly from advancements in patient-specific implant design, additive manufacturing/3D printing, and material use in recent years. We present a technique for scaphoid replacement using a patient-specific prosthesis and reconstruction of intrinsic and extrinsic ligaments to achieve optimal stability and mobility. [ABSTRACT FROM AUTHOR]

Poly-lactic acid (PLA) has been proposed in dentistry for several regenerative procedures owing to its biocompatibility and biodegradability. However, the presence of methyl groups renders PLA hydrophobic, making the surface less ideal for cell attachment, and it does not promote tissue regeneration. Upgrading PLA with inductive biomaterial is a crucial step to increase the bioactivity of the PLA and allow cellular adhesion. Our purpose is to evaluate biocompatibility, bioactivity, cellular adhesion, and mechanical properties of 3D-printed PLA scaffold coated with poly-dopamine (PDA) and nano-hydroxyapatite (n-HA) versus PLA and PLA/n-HA scaffolds. The fused deposition modelling technique was used to print PLA, PLA with embedded n-HA particles, and PLA scaffold coated with PDA/n-HA by immersion. After matrices characterization for their chemical composition and surface properties, testing the compressive strength was pursued using a universal testing machine. The bioactivity of scaffolds was evaluated by monitoring the formation of calcium phosphate compounds after simulated body fluid immersion. The PLA/PDA/n-HA scaffold showed the highest compressive strength which was 29.11 ± 7.58 MPa with enhancing calcium phosphate crystals deposition with a specific calcium polyphosphate phase formed exclusively on PLA/PDA/n-HA. With cell viability assay, the PDA/n-HA-coated matrix was biocompatible with increase in the IC50, reaching ⁓ 176.8 at 72 without cytotoxic effect on the mesenchymal stem cells, promoting their adhesion and proliferation evaluated by confocal microscopy. The study explored the biocompatibility, bioactivity, and the cell adhesion ability of PDA/n-HA coat on a 3D-printed PLA scaffold that qualifies its use as a promising regenerative material. [ABSTRACT FROM AUTHOR]

Learning cardiac morphology largely involves spatial abilities and studies indicate benefits from innovative 3D visualization technologies that speed up and increase the learning output. Studies comparing these teaching tools and their educational output are rare and few studies include complex congenital heart defects. This study compared the effects of 3D prints, mixed reality (MR) viewing of 3D meshes and standard cardiac CT slice images on medical students′ understanding of complex congenital heart defect morphology, measuring both objective level of understanding and subjective educational experience. The objective of this study was to compare morphological understanding and user experiences of 3D printed models, MR 3D visualization and axial 2D CT slices, in medical students examining morphological details in complex congenital heart defects. Medical students in the median 4th year of study (range 2nd to 6th) examined three of five different complex congenital heart defects by three different modalities: 3D printed model, MR viewed 3D mesh, and cardiac CT slices, answering a questionnaire on morphology and user experience. Time to complete task, diagnostic accuracy, and user experience data were collected and compared on group level. Task times were similar for all modalities. The percentage of correct answers was higher with MR visualization, which was also the preferred modality overall. Medical students both prefer and better understand the morphology of complex congenital heart disease with 3D models viewed using MR, without spending more time than with 3D prints or 2D CT images. [ABSTRACT FROM AUTHOR]

In this work, we proposed a novel 3D-printed manufactured electrode system. A project was developed and optimized, compatible with commercially available potetiostats. Additive manufacturing included the modification of the pseudo-reference electrode by electrodeposition of silver and its subsequent oxidation to the Ag/AgCl form. Then the system was tested using electrochemical techniques to check the application as a universal electroactive platform. As an example, we checked the detection of paracetamol as a common substance from non-steroidal anti-inflammatory drugs (NSAIDs). Finally, the system was compared to available commercial carbon electrodes, considering the screen-printed electrode (SPE no.1 and SPE no.2) and the glassy carbon electrode (GCE), showing higher sensitivity and linearity range compared to commercial screen-printed systems. The novelty of the proposed platform unveils a new way of common, simple, budget, and fast obtaining a universal electroactive platform for electrochemical research, keeping high-performance parameters. [ABSTRACT FROM AUTHOR]

Large segment bone defects pose a significant challenge in the field of orthopedic surgery, requiring effective and innovative approaches for restoration. However, many existing scaffolds are bioinert and do not support crucial processes such as cell adhesion, proliferation, and vascularization. In this study, a dual‐bionic 3D printing bredigite scaffold is developed, featuring a combination of physical structure and bioactive functions. Specifically, the structure‐mimetic scaffold has an isotropic single‐cell structure suitable for defects with varying load‐bearing requirements and allowing the ingrowth of vessels and bone. Meanwhile, an extracellular matrix peptide‐mimetic β‐amino acid polymer DM50CO50 and deferoxamine are modified onto the scaffold simultaneously to promote the adhesion of bone marrow mesenchymal stem cells and vascularization. The dual‐bionic scaffolds demonstrate outstanding osteogenic and angiogenic properties in a rat model with large segment bone defects to promote bone restoration, implying a promising strategy in designing scaffolds to promote osteoconductivity and angiogenesis for large segment bone restoration. [ABSTRACT FROM AUTHOR]

The most common surgical procedure to manage the malunion of the bones is corrective osteotomy. The current gold standard for securing the bone segments after osteotomy is the use of titanium plates and allografts which have disadvantages such as possible allergic reaction, additional operations such as extraction of the graft from other sites and removal operation. The utilization of resorbable materials presents an opportunity to mitigate these drawbacks but has not yet been thoroughly researched in the literature. This study assesses the viability of using biodegradable, 3D-printed patient-specific implants made of Poly(-L-lactide-co-D, L-lactide) (PLDLLA) and β-Tricalcium Phosphate (β-TCP) as an alternative material in an in-vitro biomechanical study involving ex vivo biomechanical compression testing, biodegradation testing, and calorimetric measurements. These implants possess a unique shape, resembling a wedge and are fixated as a connection between the osteotomised bone using resorbable screws. Following point-of-care virtual planning, bio-mechanical compressive tests with (n = 5) ex vivo radii equipped with PLDLLA/ β-TCP implants were performed to prove sufficient stability of the connection. All PLDLLA/ β-TCP implants withstood a compressive force of at least 1ʼ211 N which exceeds the maximum force reported in literature in case of a fall from the height of one meter. Furthermore, the results showed a consistent surface chemistry and slow degradation rate. The outcomes are encouraging, establishing the groundwork for an innovative distal radius corrective osteotomy surgical method. However, further research is necessary to thoroughly evaluate the long-term biodegradability and mechanical efficacy of the implants. [ABSTRACT FROM AUTHOR]

Objectives: Cleaning splints (CSs) can facilitate interdental brush (IDB) insertion and guide IDBs during cleaning movement. Cleaning efficacy with and without CSs was to be assessed and compared for a fully dentate (FD) and a partially edentulous (PE) situation. Methods: For two maxillary typodont models simulating either an FD situation or a PE situation with every second tooth missing, suitable IDBs were selected and each cleaning splint was designed and fabricated by 3D-printing. Before and after standardized cleaning, model teeth were photographed at three timepoints: (T1) clean surface, (T2) surface coated with artificial plaque, and (T3) after IDB cleaning. For each of the four test groups differing in dental status (FD, PE) and CS use (without, with), n = 10 tests/group were completed. After aligning corresponding photographs, pixel-based color difference ratios (T2-T3)/(T2-T1) were calculated. Approximal cleaning efficacy was set as the mean value over predefined regions of interest. Effects of CS use and dental status were analyzed with two-way ANOVA (α = 0.05). Results: CS use significantly improved mean approximal cleaning efficacy for the PE model (p = 0.001), whereas no difference was found with the FD model (p = 0.381). Improved cleaning efficacy with the PE model was only found in combination with a CS (factor combination model × CS use: p = 0.003). Conclusions: Cleaning splints might have the potential to improve interproximal hygiene and can be recommended for clinical use. Clinical studies should validate the results of this in vitro study and clarify if CSs could be beneficial for patients with restricted manual skills. [ABSTRACT FROM AUTHOR]

In this study, we used the three-dimensional (3D) printing method to design and fabricate a radar-absorbing structure (RAS) to protect against damage caused by lightning strikes. A carbon black-dispersed 3D filament was used as reinforcement in the composite, and metalized fibers served as the feedstock for 3D-printing. The return losses measured in the X-band and Ku-band (8.2–18 GHz) indicated a maximum return loss of −28.98 dB at 10.68 GHz, with a broad bandwidth of 6.56 GHz in the frequency range of 8.2-18 GHz. A coupled electrical–thermal analysis confirmed that the proposed carbon black-dispersed filament provided conductive paths, which contributed to direct current, energy dissipation, and lightning strike protection. The 3D-printing method ensured a sufficient level of electrical conductivity, limiting the area and depth of damage caused by lightning strikes. Therefore, 3D-printed-RASs, reinforced by electrically conductive materials, can effectively protect against lightning strikes. [ABSTRACT FROM AUTHOR]

Featured Application: The use of 3D printing technology in denture fabrication presents significant advancements over traditional methods. This technique allows for precise, customizable, and efficient manufacturing of denture bases, addressing key issues such as production time and cost. Recent studies focus on enhancing the properties of 3D-printed denture materials, such as their color stability, mechanical strength, and biocompatibility. These developments render 3D printing a critical tool for integrating advanced materials into routine dental practice, ultimately improving patient outcomes and the aesthetic longevity of dentures. Newly developed 3D-printed polymer materials are used for denture base fabrication. The aim of the present study was to evaluate the color stability of two new 3D-printed resins, a hard PPMA-based and a soft Urethane-based resin, in relation to a traditional heat-polymerized PMMA resin, which was used for comparison purposes. Specimens of the materials were immersed in five solutions (distilled water, red wine, black tea, coffee, and Coke®) for definite periods of time (one day, one week, and one month). The color measurements were carried out utilizing a spectrometer supported by a microscope and using special software. Color changes between immersion periods were calculated and statistically compared. The results showed that all types of resins were influenced during immersion periods. The heat-polymerized resin was influenced less than the others but with no significant difference to the 3D-printed hard PMMA resin. In respect to the materials compared, the discoloration effect for the 1 month immersion time was significantly more intense for the soft 3D-printed resin. In respect to the solutions' staining effects, black tea and red wine significantly discolored all materials regardless of immersion periods. The new 3D-printed materials need further improvements for dental use. [ABSTRACT FROM AUTHOR]