Innovative 3D Navigation Module for Precise Unilateral Pedicle Screw Combined with Contralateral Translaminar Facet Screw Placement in Lumbar Spine Surgery.

OBJECTIVE: The incidence of degenerative diseases of the lumbar spine has increased in recent years. Unilateral pedicle screw combined with contralateral translaminar facet screw fixation offers the advantages of less trauma, better stability, and fewer complications. However, the surgical difficulty and suboptimal pinning accuracy of translaminar facet screw placement in clinical practice limit its use. Therefore, in this study, we designed a novel suspended 3D-printed navigation module to facilitate fast and accurate intraoperative screw placement. The aim of this study is to investigate the digital design, precise implementation, and evaluation methods for placing unilateral pedicle screws in the lumbar spine combined with translaminar facet screw placement using a new suspended 3D navigation module. METHODS: This retrospective study included 46 patients with single-level lumbar lesions who underwent spine surgery at the Affiliated Hospital of Putian University between June 2022 and December 2023. The suspended navigation module was designed digitally. Preoperative screw placement was simulated using 3D printed models, followed by an intraoperative accurate screw placement facilitated by the navigation module and a postoperative evaluation of the accuracy of screw placement. The absolute difference in three-dimensional coordinates of the inlet and outlet points of the preoperative design and the postoperative screw-nail channel served as the precision index. RESULTS: In a study involving 46 patients, surgery was successful with 92 pedicle screws and 46 translaminar facet screws placed without any penetration of the cortex. The difference in coordinates before and after screw insertion was minimal, with entry points varying between 1.21 to 1.36 mm and exit points between 1.97 to 2.46 mm. When screw accuracy met certain thresholds, there was no significant difference between preoperative design and postoperative coordinates, indicating precise replication of the surgical plan. CONCLUSION: The new suspended 3D navigation module enables the precise placement of unilateral pedicle screws in the lumbar spine combined with translaminar pedicle screws for precise surgery.

Discovering the barriers to scaling a co-design approach for the provision of custom assistive technology within healthcare services.

Introduction: Using computer-aided design and 3D printing within a co-design process to produce assistive technology (AT) has a positive impact in delivering customised solutions to end-users' needs. However, to date its adoption within healthcare services has been limited. This work aims to gather clinicians' insights to identify and analyse barriers inherent in the AT design, manufacturing, and provision processes and inform a detailed understanding of the current AT eco-system. It forms part of a long-term ambition to efficiently scale up a service for the co-design of custom AT across specialties and healthcare services.Methods: Five interactive workshops were run with 21 healthcare professionals currently involved in AT provision. Participants were recruited from two health boards in the UK. Thematic analysis was used to identify common barriers to scaling up a custom AT approach. Additionally, an eco-system map was created to determine the key stakeholders and their interactions.Results: Nineteen descriptive themes, grouped into four analytical themes, were identified related to the design of AT, access to AT, healthcare staffing and healthcare system pressures. The eco-system map identified sixteen individual stakeholders and ten different groups of significant corporate stakeholders.Discussion: The identified barriers relate to both the provision of off-the-shelf and the co-design of customised AT. Further promoting the scaling up of a co-design custom AT process requires: improving communication between stakeholders, enabling information about AT to be easily accessible, ensuring feedback is gathered and used, and creating tools that enable non-expert designers to modify custom AT designs safely and effectively.

The provision of custom assistive technology (AT) needs to centre around engaging end-users from the outset to set goals, manage expectations and educate individuals on the solutions available.A digital platform needs to be developed that incorporates a user-friendly repository with clear information about off-the-shelf and custom AT solutions available.The platform should facilitate easy communication between healthcare services and the end-users of AT and enable feedback to be easily gathered and shared.The scaling up of co-design processes for the provision of custom AT within healthcare services requires training of non-expert designers in digital design and manufacturing and the creation of more user-friendly computer aided design tools.

Efficient digital design of ganglion cells in the retinal pathway.

Spiking networks, the third generation of neural networks, are presented as low-power consumption machines with higher cognitive ability, one of the main concerns in intelligence machines. In fact, neuromorphic systems are hardware implementations of spiking networks with minimum resource, area, and power consumption while preserve maximum working frequency. Here, the focus is on the digital implementation of Retinal Ganglion Cell (RGC) based on the linear approximation of non-linear terms which is called Linear Retinal Ganglion Cell (LRGC). The low-cost hardware design of biological cells is acceptable when the digital model of the cell has the same phase and time domain behavior as the original model and follows the dynamic behavior of the original model accurately, which is discussed and confirmed with different analyzes in this paper. The low-cost hardware design of biological cells allows the optimal implementation of a neural population on the hardware, provided that the collective behavior of the digital model matches the original model which is approved by the large-scale simulation of RGC and LRGC models. Cognitive processes are performed in the nervous system at a very low cost, which neuromorphic systems are trying to achieve this important. In this regard, the behavior of RGC and LRGC models in the reconstruction of the image through the retina pathway was examined and a high agreement between the performance of the two models was achieved. Finally, the high functional compatibility of RGC, LRGC models proves that the proposed model is a good candidate of the main model in neuromorphic systems with low hardware cost.

Multi-stage 3D-printed guide for precise restoration of severely inclined teeth based on target restorative space guidance: a case report.

In clinical dentistry, addressing unique conditions such as tilted, elongated, and torsion teeth during preparation can be effectively managed through digital tooth morphology design. The production of a multi-stage 3D-printed guide offered a more efficient and accurate solution. This article presented a case of significant inclination, elongation, and torsion in the maxillary and mandibular canines that were successfully treated using crown restoration modification. A crown preparation guide was fabricated based on the final form design of the restoration using the target restorative space analysis technique to ensure precise tooth preparation. A tooth preparation guide was also designed and utilized further to enhance accuracy and efficiency during complex tooth preparation. The combined application of these multi-stage guides demonstrated promising clinical prospects.

Integrating digital design with 3D printing technology achieves customized and precise approaches for flap transplantation to facilitate fingertip defect surgery.

OBJECTIVE: This study investigates the clinical efficacy of integrating digital design with three-dimension (3D) printing technology in the transplantation of flaps for fingertip defects. METHODS: A retrospective analysis was conducted from October 2019 to June 2021 on 90 cases of patients with fingertip defects. These included 45 cases in which digital design, coupled with 3D printing, assisted the operation (3D printing group), and another 45 cases where patients underwent traditional pedicle flap transplantation and skin grafting (traditional operation group). A six-month postoperative follow-up assessed various measurements between the two groups, comparing the skin flap survival rate, aesthetic outcome, cold intolerance, sensory recovery, and overall skin flap performance. RESULTS: ① Statistical analysis utilizing the independent samples t-test revealed a significant reduction in both operation time and flap anastomosis rate for the 3D printing group compared to the traditional operation group (P < 0.05). ② Conversely, the survival rate, aesthetic outcome, and cold intolerance showed no significant disparities between the groups (P > 0.05). ③ Further, the Mann-Whitney U test indicated no significant difference in sensory recovery and overall efficacy assessment between the two cohorts (P > 0.05). CONCLUSION: Integrating digital design with 3D printing technology facilitated the surgical management of fingertip defects, achieving customized and precise approaches in flap transplantation. This precision in personalized skin flap design contributed to reduced operative time and enhanced surgical efficiency in such procedures.

Alberta reconstructive technique (ART): An innovative approach using digital surgical design and simulation in advanced jaw reconstruction with occlusion-based prefabricated vascularized fibular flaps and primary osseointegrated implant installation.

The Alberta reconstructive technique (ART) is an innovative surgical procedure performed on patients undergoing primary jaw resection and reconstruction. The ART procedure was developed in collaboration with the Institute for Reconstructive Sciences in Medicine and the Division of Otolaryngology-Head and Neck Surgery, University of Alberta.

A Modified Technique for Simplifying Full-Arch Screw-Retained Implant Rehabilitation With Rapid Digital Conversion: A Case Report.

In this case report, a new modified technique is described for an efficient, simple, and effective digital approach to immediate provisionalization of the implant-supported full-arch prosthesis. Today's patient population is increasingly educated about treatment options and expects efficient, esthetic, and comfortable results. This novel technique delivers on these aims while eliminating the many challenges posed by previously described digital and analog techniques to the immediate provisionalization of the implant-supported full-arch prosthesis. This technique requires minimal chair time and cost to the provider and reduces patient discomfort and complication risk. This technique therefore presents a promising new protocol for this popular procedure.

Quality by Digital Design for Developing Platform RNA Vaccine and Therapeutic Manufacturing Processes.

Quality by digital design (QbDD) utilizes data-driven, mechanistic, or hybrid models to define and optimize a manufacturing design space. It improves upon the QbD approach used extensively in the pharmaceutical industry. The computational models developed in this approach identify and quantify the relationship between the product's critical quality attributes (CQAs) and the critical process parameters (CPPs) of unit operations within the manufacturing process. This chapter discusses the QbDD approach in developing and optimizing unit operations such as in vitro transcription, tangential flow filtration, affinity chromatography, and lipid nanoparticle (LNP) formulation in mRNA vaccine manufacturing. QbDD can be an efficient framework for developing a production process for a disease-agnostic product that requires extensive experimental and model-based process-product interaction characterization during the early process development phase.

Application of 3D printed titanium mesh and digital guide plate in the repair of mandibular defects using double-layer folded fibula combined with simultaneous implantation.

Fibula transplantation plays an irreplaceable role in restoring the function and morphology of the defected mandible. However, the complex load-bearing environment of the mandible makes it urgent to accurately reconstruct the mandible, ensure the position of the condyle after surgery, and restore the patient's occlusal function and contour. The intervention of digital design and three-dimensional (3D) printed titanium mesh provides a more efficient method and idea to solve this problem. Digital design guides the accurate positioning, osteotomy, and simultaneous implant placement during surgery, and 3D printed titanium mesh ensures stable condyle position after surgery, restoring good mandibular function. The double-layer folded fibula maintains the vertical height of the mandible and a good facial contour, and simultaneous implant placement can establish a good occlusal relationship. This study conducted a retrospective analysis of five patients with jaw defects who underwent digital fibula reconstruction over the past 3 years. It was found that the surgical protocol combining digital design, 3D printed intraoperative guides, 3D printed titanium mesh, free fibula flap, immediate implant, and occlusal reconstruction to repair jaw defects had more ideal facial appearance and biological function. It will provide a more reliable surgical protocol for clinical management of large mandibular defects.

Efficient digital design of the nonlinear behavior of Hindmarsh-Rose neuron model in large-scale neural population.

Spiking networks, as the third generation of neural networks, are of great interest today due to their low power consumption in cognitive processes. This important characteristic has caused the hardware implementation techniques of spiking networks in the form of neuromorphic systems attract a lot of attention. For the first time, the focus is on the digital implementation based on CORDIC approximation of the Hindmarsh-Rose (HR) neuron so that the hardware implementation cost is lower than previous studies. If the digital design of a neuron is done efficient, the possibility of implementing a population of neurons is provided for the feasibility of low-consumption implementation of high-level cognitive processes in hardware, which is considered in this paper through edge detector, noise removal and image magnification spiking networks based on the proposed CORDIC_HR model. While using less hardware resources, the proposed HR neuron model follows the behavior of the original neuron model in the time domain with much less error than previous study. Also, the complex nonlinear behavior of the original and the proposed model of HR neuron through the bifurcation diagram, phase space and nullcline space analysis under different system parameters was investigated and the good follow-up of the proposed model was confirmed from the original model. In addition to the fact that the individual behavior of the original and the proposed neurons is the same, the functional and behavioral performance of the randomly connected neuronal population of original and proposed neuron model is equal. In general, the main contribution of the paper is in presenting an efficient hardware model, which consumes less hardware resources, follows the behavior of the original model with high accuracy, and has an acceptable performance in image processing applications such as noise removal and edge detection.

Clinical application of perforator vessel location guide plate for fibular musculocutaneous flaps / 口腔疾病防治

Objective@#Based on 3D printing technology, explore the precision of a perforator vessel location guide plate for fibular musculocutaneous flaps before the transplantation of fibular osteocutaneous flaps and evaluate its application effects.@*Methods@#This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. From May 2019 to October 2022, 14 patients with jaw defects who needed to undergo fibular perforator flap transplantation at the First Affiliated Hospital of Xinjiang Medical University were selected. For the seven patients in the guide plate group, CTA was combined with Mimics software to reconstruct both lower limbs, and the perforator vessel positioning guide for locating perforator vessels was designed; the two ends of the guide plate were designed as fixed ends, with the upper end fixed to the knee joint and the lower end fixed to the ankle joint, and the guide plate was fabricated by a 3D printer. For the seven patients in the control group, a conventional handheld Doppler probe was used for perforator vessel location. The average operation time, bleeding volume, recovery time, deviation of perforator vessel location, postoperative flap-related complications, postoperative donor site shape satisfaction, and lower extremity functional scale (LEFS) score were recorded. SPSS 25.0 software was used for statistical analysis.@*Results@#The average operation time, bleeding volume, recovery time, deviation of perforator vessel location and postoperative donor site shape satisfaction were significantly better in the guide plate group than in the control group (P<0.05); moreover, the differences in postoperative flap-related complications and LEFS scores were not statistically significant (P>0.05).@*Conclusion@#Based on 3D printing technology, fibular musculocutaneous flap perforator vessels can be more accurately located using a guide plate and the knee and ankle as fixed points, and this method can effectively stabilize the guide position, prevent soft tissue offset, and improve positioning accuracy and thus deserves to be generalized.

A digital orthodontic arch wire design system with interactive adjustment and intelligent optimization.

The design of orthodontic arch wires is a prerequisite for orthodontic treatment that determines the subsequent orthodontic effects. Current methods for designing orthodontic arch wires are often based on traditional manual techniques, which suffer from problems such as low accuracy and efficiency. To address these issues, a digital orthodontic arch wire design system has been developed using Unity 3D and C#. This system allows for the interactive adjustment and intelligent optimization of the shape of digital orthodontic arch wires. The developed system includes modules for curve design, contour construction, and collision detection of orthodontic arch wires, which can be customized interactively to meet the personalized needs of patients. In addition, an energy-constrained method is employed to optimize the shape of certain regions of the arch wire, which helps overcome distortion and interference issues caused by unreasonable interaction. The effectiveness of the developed system has been evaluated through experiments on digital design and optimization of orthodontic arch wires. Results demonstrate that the system can achieve accurate and efficient digital design of orthodontic arch wires, effectively reduce distortion, and is expected to improve the orthodontic effect.

Simultaneous implantation and tooth preparation technology guided by 3D-printed guide.

Using digital technologies in concurrently performing missing tooth implantation and preparation of remaining teeth is a solution to reduce the number of visits and improve efficiency. This paper proposes a digital process for simultaneously implanting and preparing teeth. It integrates implant surgical guide and 3D-printed tooth preparation guide into a single guide and completes guided implant placement and precise tooth preparation. Based on "repair-oriented" virtual implant planning, the implant surgical guide can improve the efficiency and predictability of implant placement, and its linear accuracy is about 1 mm. The tooth preparation guide precisely guides tooth preparation and restoration space visualization, ensuring the quality of the tooth preparation. The two guides have different design accuracy requirements, and thus their combination improves the overall guiding accuracy requirements. The concurrent application of the two guides minimizes the clinical operation time, number of visits, and economic burden of patients.

Smile Design and Treatment Planning-Conventional versus Digital-A Pilot Study.

INTRODUCTION: Several methods are currently available for providing a preview of the prosthodontic treatment, including computer simulations, 3D models, wax-ups, and mock-ups. The aim of this study is to compare the aesthetic aspects and assessment of conventional versus digital prefigurative methods. METHODS: The study included 5 patients and 3 observers, for each of whom a wax-up was made in both the conventional and digital techniques. The analog method, which implied a mock-up molding with a silicone matrix of the wax-up, was compared to a digital workflow, which consisted of a mock-up milling from a digital design. The patient's clinical mock-ups were recorded with digital photographs and assessed for nine different criteria by three observers. RESULTS: The analysis has shown a balanced assessment of the aesthetic criteria without any significant difference between the analog and digital prefigurative methods. CONCLUSIONS: Between the two wax-ups (conventional and digital), there were some variations in smile and dental criteria; however, the obtained data were very similar. When it comes to the smile criteria, the general average grades of the mock-ups conducted using the conventional method are slightly higher than the ones using the digital technique.

Automated and data-driven plate computation for presurgical cleft lip and palate treatment.

PURPOSE: Presurgical orthopedic plates are widely used for the treatment of cleft lip and palate, which is the most common craniofacial birth defect. For the traditional plate fabrication, an impression is taken under airway-endangering conditions, which recent digital alternatives overcome via intraoral scanners. However, these alternatives demand proficiency in 3D modeling software in addition to the generally required clinical knowledge of plate design. METHODS: We address these limitations with a data-driven and fully automated digital pipeline, endowed with a graphical user interface. The pipeline adopts a deep learning model to landmark raw intraoral scans of arbitrary mesh topology and orientation, which guides the nonrigid surface registration subsequently employed to segment the scans. The plates that are individually fit to these segmented scans are 3D-printable and offer optional customization. RESULTS: With the distance to the alveolar ridges closely centered around the targeted 0.1 mm, our pipeline computes tightly fitting plates in less than 3 min. The plates were approved in 12 out of 12 cases by two cleft care professionals in a printed-model-based evaluation. Moreover, since the pipeline was implemented in clinical routine in two hospitals, 19 patients have been undergoing treatment utilizing our automated designs. CONCLUSION: The results demonstrate that our automated pipeline meets the high precision requirements of the medical setting employed in cleft lip and palate care while substantially reducing the design time and required clinical expertise, which could facilitate access to this presurgical treatment, especially in low-income countries.

3D printed multi-drug-loaded suppositories for acute severe ulcerative colitis.

Acute severe ulcerative colitis (ASUC) is a growing health burden that often requires treatment with multiple therapeutic agents. As inflammation is localised in the rectum and colon, local drug delivery using suppositories could improve therapeutic outcomes. Three-dimensional (3D) printing is a novel manufacturing tool that permits the combination of multiple drugs in personalised dosage forms, created based on each patient's disease condition. This study, for the first time, demonstrates the feasibility of producing 3D printed suppositories with two anti-inflammatory agents, budesonide and tofacitinib citrate, for the treatment of ASUC. As both drugs are poorly water-soluble, the suppositories' ability to self-emulsify was exploited to improve their performance. The suppositories were fabricated via semi-solid extrusion (SSE) 3D printing and contained tofacitinib citrate and budesonide in varying doses (10 or 5 mg; 4 or 2 mg, respectively). The suppositories displayed similar dissolution and disintegration behaviours irrespective of their drug content, demonstrating the flexibility of the technology. Overall, this study demonstrates the feasibility of using SSE 3D printing to create multi-drug suppositories for the treatment of ASUC, with the possibility of titrating the drug doses based on the disease progression.

Off-World Mental Health: Considerations for the Design of Well-being-Supportive Technologies for Deep Space Exploration.

During future long-duration space exploration missions, humans will be exposed to combinations of extreme physical, psychological, and interpersonal demands. These demands create risks for the safety, performance, health, and well-being of both individuals and crew. The communication latency in deep space means that explorers will increasingly have to operate independently and take responsibility for their own self-care and self-management. At present, several research programs are focused on developing and testing digital technologies and countermeasures that support the effective functioning of deep space crews. Although promising, these initiatives have been stimulated mostly by technological opportunity rather than cogent theory. In this perspective, we argue that digital technologies developed for spaceflight should be informed by well-being-supportive design principles and be cognizant of broader conversations around the development and use of digital health applications, especially pertaining to issues of autonomy, privacy, and trust. These issues are important for designing potentially mission-critical health technologies and may be determining factors in the safe and successful completion of future off-world endeavors.

Accuracy and digital screw path design of TiRobot-assisted pedicle screw placement for lumbar spondylolisthesis.

PURPOSE: To investigate lumbar spondylolisthesis screw placement assisted by TiRobot in terms of digital screw path design, accurate implementation, and accuracy evaluation method. METHODS: In this study, we enrolled 40 patients with lumbar spondylolisthesis between December 2020 and August 2021 who underwent spine surgery at the Affiliated Hospital of PuTian University. Pre-operative computed tomography position and screw path designation, intra-operative pedicle screw placement according to pre-operative planning, and post-operative evaluation of the accuracy of screw placement were performed. 3D coordinates of the entry and exit points before and after the operation were collected. The qualified points at different levels of accuracy were counted. The screw placement accuracy was based on the absolute difference using the Chi-squared test. RESULTS: In total, 194 screws were successfully implanted with no screws penetrating the cortex. The absolute difference of entry points X, Y, and Z coordinates before and after the operation was 0.425 ± 0.294 mm, 0.417 ± 0.310 mm, and 0.466 ± 0.327 mm, respectively. The corresponding values in terms of exit points were 0.702 ± 0.470 mm, 0.963 ± 0.595mm, and 0.983 ± 0.566 mm, respectively. No obvious differences in coordinates before and after the operation were observed with an entry point degree of accuracy of ≥ 1.2 mm and exit point degree of accuracy of ≥ 2.1 mm. Therefore, the real surgery was consistent with the design. CONCLUSIONS: TiRobot-assisted lumbar spondylolisthesis surgery achieved optimal path designation and precise surgery.

Simultaneous implantation and tooth preparation technology guided by 3D-printed guide / 华西口腔医学杂志

Using digital technologies in concurrently performing missing tooth implantation and preparation of remaining teeth is a solution to reduce the number of visits and improve efficiency. This paper proposes a digital process for simultaneously implanting and preparing teeth. It integrates implant surgical guide and 3D-printed tooth preparation guide into a single guide and completes guided implant placement and precise tooth preparation. Based on "repair-oriented" virtual implant planning, the implant surgical guide can improve the efficiency and predictability of implant placement, and its linear accuracy is about 1 mm. The tooth preparation guide precisely guides tooth preparation and restoration space visualization, ensuring the quality of the tooth preparation. The two guides have different design accuracy requirements, and thus their combination improves the overall guiding accuracy requirements. The concurrent application of the two guides minimizes the clinical operation time, number of visits, and economic burden of patients.

Techno-economic analysis of dynamic, end-to-end optimal pharmaceutical campaign manufacturing using PharmaPy.

Increased interest in the pharmaceutical industry to transition from batch to continuouos manufacturing motivates the use of digital frameworks that allow systematic comparison of candidate process configurations. This paper evaluates the technical and economic feasibility of different end-to-end optimal process configurations, viz. batch, hybrid and continuous, for small-scale manufacturing of an active pharmaceutical ingredient. Production campaigns were analyzed for those configurations containing continuous equipment, where significant start-up effects are expected given the relatively short campaign times considered. Hybrid operating mode was found to be the most attractive process configuration at intermediate and large annual production targets, which stems from combining continuous reactors and semi-batch vaporization equipment. Continuous operation was found to be more costly, due to long stabilization times of continuous crystallization, and thermodynamic limitations of flash vaporization. Our work reveals the benefits of systematic digital evaluation of process configurations that operate under feasible conditions and compliant product quality attributes.