Clinical efficacy and effectiveness of 3D printing: a systematic review

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.

Update on recent advances in amyotrophic lateral sclerosis

In the last few years, our understanding of disease molecular mechanisms underpinning ALS has advanced greatly, allowing the first steps in translating into clinical practice novel research findings, including gene therapy approaches. Similarly, the recent advent of assistive technologies has greatly improved the possibility of a more personalized approach to supportive and symptomatic care, in the context of an increasingly complex multidisciplinary line of actions, which remains the cornerstone of ALS management. Against this rapidly growing background, here we provide an comprehensive update on the most recent studies that have contributed towards our understanding of ALS pathogenesis, the latest results from clinical trials as well as the future directions for improving the clinical management of ALS patients.

Utilization of a 3D-Printed Mandibular Jaw for Ridge Reconstruction in Periodontics: A Case Report

Three-dimensional (3D) printing is an emerging manufacturing technology in dentistry with a range of applications. Digital dentistry presented in cone beam CT scan radiographs is a revolution that improved surgical outcomes by optimizing accurate diagnosis and analysis of the surgical sites before surgery. A periodontist can modify the treatment plan, surgical techniques, and incision design based on bone defects seen on cone beam CT scans. Block grafting has been a technique of choice when wound stability is required for guided bone regeneration. There was no significant difference between the different surgical procedures for reconstruction and choice should be given to the simpler and less invasive procedure. A xenograft or allograft block can work as an alternative to the autogenous bone block to reduce the surgery time and patient morbidity. Preparation and shaping of block graft during surgery time to match the defect shape can prolong the operative time, reduce the treatment success, and increase postoperative complications. In this case report, a sterilized 3D-printed mandibular jaw was utilized to visualize the defect size and shape. A bovine xenograft block was then prepared, shaped, and adapted on the 3D-printed jaw 30 minutes before the surgery. The block graft was then transferred and well-fitted on the surgical defect. Handling experience was greater and surgery time and postoperative pain were reduced.

3D printing of heart valves

3D printing technologies have the potential to revolutionize the manufacture of heart valves through the ability to create bespoke, complex constructs. In light of recent technological advances, we review the progress made towards 3D printing of heart valves, focusing on studies that have utilised these technologies beyond manufacturing patient-specific moulds. We first overview the key requirements of a heart valve to assess functionality. We then present the 3D printing technologies used to engineer heart valves. By referencing International Organisation for Standardisation (ISO) Standard 5840 (Cardiovascular implants - Cardiac valve prostheses), we provide insight into the achieved functionality of these valves. Overall, 3D printing promises to have a significant positive impact on the creation of artificial heart valves and potentially unlock full complex functionality.

Effect of laparoscopic handle size on surgical performance: A randomized crossover trial

Laparoscopic instrument handles design and dimensions are crucial to determine the configuration of surgeons' hand grip and, therefore, can have a deleterious effect on overall surgical efficiency and surgeons' comfort. The aim of this study is to investigate the impact of laparoscopic handle size and hand surface area on surgical task performance. A single-blind, randomized crossover trial was carried out with 29 novice medical students. Participants performed three simulated tasks in "black box" simulators using two scissor-type handles of different sizes. Surgical performance was assessed by the number of errors and time required to complete each task. Hand anthropometric data were measured using a 3D scanner. Execution time was significantly higher when cutting and suturing tasks were performed with the smaller handle. In addition, hand surface area was positively correlated with peg transfer task time when performed with the standard handle and was correlated with cutting task time in small and standard handle groups. We also found positive correlations between execution time and the number of errors executed by larger-handed participants. Our findings indicate that laparoscopic handle size and hand area influence surgical performance, highlighting the importance of considering hand anthropometry variances in surgical instrument design.

Emerging Technologies in Hand Orthopedic Surgery: Current Trends and Future Directions

Emerging technologies are changing hand surgery by improving surgical precision, minimizing tissue disruption, and expediting patient recovery. These advancements have the potential to revolutionize surgical procedures, patient outcomes, and rehabilitation processes. However, there are still challenges that need to be addressed before these technologies can be widely adopted. These challenges include the learning curve for surgeons, high costs, and ethical considerations. Future research should focus on addressing the limitations of these technologies, exploring their long-term effects, and evaluating their cost-effectiveness. To successfully implement them, a collaborative approach involving clinicians, researchers, engineers, and policymakers is necessary. This review provides an overview of current and future trends in emerging technologies for hand orthopedic surgery.

Potentiometric detection of apomorphine in human plasma using a 3D printed sensor

Apomorphine is a dopamine agonist that is used for the management of Parkinson's disease and has been proven to effectively decrease the off-time duration, where the symptoms recur, in Parkinson's disease patients. This paper describes the design and fabrication of the first potentiometric sensor for the determination of apomorphine in bulk and human plasma samples. The fabrication protocol involves stereolithographic 3D printing, which is a unique tool for the rapid fabrication of low-cost sensors. The solid-contact apomorphine ion-selective electrode combines a carbon-mesh/thermoplastic composite as the ion-to-electron transducer and a 3D printed ion-selective membrane, doped with the ionophore calix[6]arene. The sensor selectively measures apomorphine in the presence of other biologically present cations - sodium, potassium, magnesium, and calcium - as well as the commonly prescribed Parkinson's pharmaceutical, levodopa (L-Dopa). The sensor demonstrated a linear, Nernstian response, with a slope of 58.8 mV/decade over the range of 5.0 mM-9.8 μM, which covers the biologically (and pharmaceutically) relevant ranges, with a limit of detection of 2.51 μM. Moreover, the apomorphine sensor exhibited good stability (minimal drift of just 188 μV/hour over 10 h) and a shelf-life of almost 4 weeks. Experiments performed in the presence of albumin, the main plasma protein to which apomorphine binds, demonstrate that the sensor responds selectively to free-apomorphine (i.e., not bound or complexed forms). The utility of the sensor was confirmed through the successful determination of apomorphine in spiked human plasma samples.

In-house 3D-printed custom splints for non-operative treatment of distal radial fractures: a randomized controlled trial

We compared patient satisfaction and clinical effectiveness of 3D-printed splints made of photopolymer resin to conventional fibre glass casts in treating distal radial fractures. A total of 39 patients with minimally displaced distal radius fractures were included and randomized. Of them, 20 were immobilized in a fibre glass cast and 19 in a 3D-printed forearm splint. The 3D-printed splints were custom-designed based on forearm surface scanning with a handheld device and printed in-house using digital light processing printing technology. Patient satisfaction and clinical effectiveness were assessed with questionnaires 1 and 6 weeks after the initiation of immobilization. Fracture healing, pain, range of motion, grip strength and the DASH and PRWE scores were assessed up to 1-year follow-up. 3D-printed splints proved to be equally well tolerated by the patients and equally clinically effective as conventional fibre glass casts although there was a higher rate of minor complications. 3D-printed splints present a safe alternative, especially in young, active patients, for non-operative treatment of distal radial fractures.Level of evidence: I.

User perspectives of digital manufacturing for lower-limb prosthetic sockets

BACKGROUND

There is growing interest to use digital technology (DT) for manufacturing lower-limb prosthetic sockets to improve efficiency and clinical outcomes. However, little is known about how lower-limb prosthesis users perceive DTs, such as 3D scanning and 3D printing.

OBJECTIVES

This study aimed to provide an understanding of perceptions and experiences with DT for prosthetic socket manufacturing from the perspective of prosthesis users.

STUDY DESIGN

A qualitative descriptive research study.

METHODS

Nine lower-limb prosthesis users (mean age 56; 5 female; 4 male) participated in one-on-one semistructured telephone interviews. Inductive thematic analysis was performed to identify a codebook and emerging themes from the interview transcripts.

RESULTS

Two major themes were identified: (1) expectations and prioritization of 3D printed socket usability and (2) facilitators and barriers to uptake of DT among patients.

CONCLUSION

DT methods were found to be acceptable and feasible from a patient perspective, although technological advancements are still required, and real-time communication about the process may be vital for ensuring patient engagement. Consideration of these findings may improve patient satisfaction to emerging prosthesis treatment plans and ultimately support widespread adoption of DT as an additional tool for fabricating prosthetic sockets.

Advanced Strategies for the Fabrication of Multi-Material Anatomical Models of Complex Pediatric Oncologic Cases

The printing and manufacturing of anatomical 3D models has gained popularity in complex surgical cases for surgical planning, simulation and training, the evaluation of anatomical relations, medical device testing and patient-professional communication. 3D models provide the haptic feedback that Virtual or Augmented Reality (VR/AR) cannot provide. However, there are many technologies and strategies for the production of 3D models. Therefore, the aim of the present study is to show and compare eight different strategies for the manufacture of surgical planning and training prototypes. The eight strategies for creating complex abdominal oncological anatomical models, based on eight common pediatric oncological cases, were developed using four common technologies (stereolithography (SLA), selectie laser sinterning (SLS), fused filament fabrication (FFF) and material jetting (MJ)) along with indirect and hybrid 3D printing methods. Nine materials were selected for their properties, with the final models assessed for application suitability, production time, viscoelastic mechanical properties (shore hardness and elastic modulus) and cost. The manufacturing and post-processing of each strategy is assessed, with times ranging from 12 h (FFF) to 61 h (hybridization of FFF and SLS), as labor times differ significantly. Cost per model variation is also significant, ranging from EUR 80 (FFF) to EUR 600 (MJ). The main limitation is the mimicry of physiological properties. Viscoelastic properties and the combination of materials, colors and textures are also substantially different according to the strategy and the intended use. It was concluded that MJ is the best overall option, although its use in hospitals is limited due to its cost. Consequently, indirect 3D printing could be a solid and cheaper alternative.

Leveraging Digital Workflows to Transition the Orthotics and Prosthetics Profession Toward a Client-Centric and Values-Based Care Model

The orthotics and prosthetics (O&P) profession has a history of responding to market demands in a reactive rather than proactive manner. This has created significant impacts including shrinkage in scope of practice and constraint in remuneration for professional services due to a fee-for-device third party payer system. Rapid changes in technology and healthcare combined with an outdated device-centric reimbursement system are creating unprecedented challenges that threaten sustainability of the O&P profession. Hence, a reassessment of the value of O&P care, and the O&P workflow process is necessary to inform an update to the value proposition and practice model for sustainability. This article reviews key factors contributing to the current state of O&P, and potential solutions involving an update in practitioner competencies, and the care delivery model (from device-centric to client-centric and values-based). Updates could be achieved by leveraging the use of digital workflows that increase efficiencies and enhance the value of clinical outcomes. Eventually, these updates could enable the O&P profession to elevate the value proposition that aligns with its most important stakeholders: client-patients and third-party reimbursement agencies in a rapidly changing technology and healthcare landscape.

3D Printing and The Evolution Of Partial Hand Prostheses: My Journey from Theory To Practice

The world of prosthetics has been undergoing significant changes, with the evolution of materials, design techniques, and manufacturing methodologies converging to redefine the landscape. Central to this narrative is the imperative for a holistic approach, harmonizing the trinity of materials, design, and methodologies to yield optimal outcomes. This balance is especially pivotal for the overlooked yet significant segment of those with partial hand and finger differences. Historically, this demographic has been underserved, with rehabilitation and prosthetic innovations often falling short. The sheer prevalence of partial hand differences underscores the urgency of tailored solutions. Traditional fabrication methods like wet lamination have posed challenges, particularly in aligning and efficiency. The advent of additive manufacturing has been transformative. The case of designing and printing a partial finger socket for Point Designs, LLC's Point Partial finger highlights this paradigm shift. Where conventional techniques demanded hours, digital design and 3D printing have condensed the process to mere minutes, without compromising on quality. This is not merely a win in terms of time efficiency; the implications for the end users are profound, ensuring a more customized and efficient solution. The journey underscores the potential of blending technology and traditional prosthetic knowledge, pointing towards a future where prosthetics align more seamlessly with users' needs.

The perioperative utility of 3D printed models in complex surgical care: feedback from 106 cases

INTRODUCTION

3D models are an emerging tool for surgical planning, providing an augmented method for the visualisation of a patient's anatomy. As their use increases, more data about the utility of these models is critical to inform budget allocation. This study provides the most comprehensive analysis to date for the use of 3D models in perioperative management.

METHODS

3D models for complex surgical cases in NHS hospitals were delivered alongside a surgeon feedback survey. The survey on the model's utility had been designed alongside the university data analytical team and focused on five areas: surgical planning and diagnosis, economic impact, impact on intraoperative and preoperative time, effect on communication and direct impact on the patient.

RESULTS

There were 106 models used by 63 surgeons for complex surgical cases between May 2020 and March 2021, across multiple surgical specialties. The models were reported to have benefits in all perioperative areas, with 92.5% of responses agreeing that the 3D model was a better method for diagnosis and planning than traditional 2D techniques. Benefits were reported on preoperative planning (92.4%), economic savings due to equipment selection (54.4%), reduction in surgical time (41.5%) and surgeon-to-surgeon communication (92.6%).

CONCLUSION

3D models were shown to have a wide range of benefits in a surgical setting. The reduction in surgical time could have the potential to help alleviate surgical backlogs. With more widespread use and optimisation of costs the use of 3D models could become the standard for unusual and complex surgical cases.

Cost-effective 3D scanning and printing technologies for outer ear reconstruction: current status

Current 3D scanning and printing technologies offer not only state-of-the-art developments in the field of medical imaging and bio-engineering, but also cost and time effective solutions for surgical reconstruction procedures. Besides tissue engineering, where living cells are used, bio-compatible polymers or synthetic resin can be applied. The combination of 3D handheld scanning devices or volumetric imaging, (open-source) image processing packages, and 3D printers form a complete workflow chain that is capable of effective rapid prototyping of outer ear replicas. This paper reviews current possibilities and latest use cases for 3D-scanning, data processing and printing of outer ear replicas with a focus on low-cost solutions for rehabilitation engineering.

Appraisal of the Accuracy and Reliability of Cone-Beam Computed Tomography and Three-Dimensional Printing for Volumetric Mandibular Condyle Measurements of a Human Condyle

Background This study aims to evaluate the accuracy of volumetric measurements of three-dimensional (3D)-printed human condyles from cone-beam computed tomography (CBCT) in comparison to physical condyles using a water displacement test. Methodology A sample of 22 dry condyles was separated from the mandibular body by disc, mounted on a base made of casting wax, and scanned using the SCANORA (Scanora 3DX, Soredex, Finland) CBCT scanner. Subsequently, the projection data were reconstructed with the machine-dedicated OnDemand 3D (Cybermed Co., Seoul, Korea). The Standard Tessellation Language file was prepared for 3D printing using chitubox slicing software v1.9.1. Frozen water-washable gray resin was used for 3D printing. All condyles were printed using the same parameters and the same resin. The volumetric measurements were then performed using a customized modified pycnometer based on water volume and weight displacement. Volumetric measures were performed for both the physical human condyles and the 3D-printed replicas and the measurements were then compared. Results The volume of dry condyles using the water displacement method showed an average (±SD) of 1.925 ± 0.40 cm3. However, the volume of 3D-printed replicas using the water displacement method showed an average (±SD) of 2.109 ± 0.40 cm3. The differences in measurements were insignificant (p > 0.05), as revealed by an independent t-test. Conclusions Highly precise, accurate, and reliable CBCT for volumetric mandibular condyle was applied for measurements of a human condyle and 3D-printed replica. The modified pycnometer for volumetric measurements presented an excellent volumetric measure based on a simple water displacement device. The tested modified pycnometer can be applied in volumetric measurements in both 3D-printed and mandibular condyle. For best accuracy, the highest scanning resolution possible should be used. As it directly handles irregularly shaped solid objects in a non-destructive manner with a high level of precision and reliability, this 3D scanning approach may be seen as a superior alternative to the current measurement methods.

A History of Innovation: Tracing the Evolution of Imaging Modalities for the Preoperative Planning of Microsurgical Breast Reconstruction

Breast reconstruction is an essential component in the multidisciplinary management of breast cancer patients. Over the years, preoperative planning has played a pivotal role in assisting surgeons in planning operative decisions prior to the day of surgery. The evolution of preoperative planning can be traced back to the introduction of modalities such as ultrasound and colour duplex ultrasonography, enabling surgeons to evaluate the donor site's vasculature and thereby plan operations more accurately. However, the limitations of these techniques paved the way for the implementation of modern three-dimensional imaging technologies. With the advancements in 3D imaging, including computed tomography and magnetic resonance imaging, surgeons gained the ability to obtain detailed anatomical information. Moreover, numerous adjuncts have been developed to aid in the planning process. The integration of 3D-printing technologies has made significant contributions, enabling surgeons to create complex haptic models of the underlying anatomy. Direct infrared thermography provides a non-invasive, visual assessment of abdominal wall vascular physiology. Additionally, augmented reality technologies are poised to reshape surgical planning by providing an immersive and interactive environment for surgeons to visualize and manipulate 3D reconstructions. Still, the future of preoperative planning in breast reconstruction holds immense promise. Most recently, artificial intelligence algorithms, utilising machine learning and deep learning techniques, have the potential to automate and enhance preoperative planning processes. This review provides a comprehensive assessment of the history of innovation in preoperative planning for breast reconstruction, while also outlining key future directions, and the impact of artificial intelligence in this field.

The regulatory challenge of 3D bioprinting

New developments in additive manufacturing and regenerative medicine have the potential to radically disrupt the traditional pipelines of therapy development and medical device manufacture. These technologies present a challenge for regulators because traditional regulatory frameworks are designed for mass manufactured therapies, rather than bespoke solutions. 3D bioprinting technologies present another dimension of complexity through the inclusion of living cells in the fabrication process. Herein we overview the challenge of regulating 3D bioprinting in comparison to existing cell therapy products as well as custom-made 3D printed medical devices. We consider a range of specific challenges pertaining to 3D bioprinting in regenerative medicine, including classification, risk, standardization and quality control, as well as technical issues related to the manufacturing process and the incorporated materials and cells.

Is the Pre-Shaping of an Orbital Implant on a Patient-Specific 3D-Printed Model Advantageous Compared to Conventional Free-Hand Shaping? A Systematic Review and Meta-Analysis

This study aimed to perform a systematic review and meta-analysis to compare pre-shaped implants on a patient-specific 3D-printed (3DP) model to manual free-hand shaping (MFS) for orbital wall reconstruction. The PRISMA protocol was followed in this study, and the review was registered in the PROSPERO database (CRD42021261594). A search was conducted in MEDLINE (PubMed), Embase, Cochrane Library, Clinicaltrials.gov, Google Scholar, and the grey literature. Ten articles were included, and six outcomes were analyzed. In total, 281 patients were in the 3DP group and 283 were in the MFS group. The studies had an overall high risk of bias. 3DP models resulted in a better accuracy of fit, anatomical angle reproduction, and defect area coverage. The correction of orbital volume was also superior with statistical significance. There was a higher percentage of the correction of enophthalmos and diplopia in the 3DP group. Intraoperative bleeding and hospital stay were reduced in the 3DP group. The meta-analysis of operative time showed a reduction in the average operative time by 23.58 min (95% CI: -43.98 to -3.19), which was statistically significant (t(6) = -2.8299, p = 0.0300). The 3DP models appear advantageous for an accurate orbital wall reconstruction, with fewer complications than those for conventional free-hand-shaped implants.

The Value of Three-Dimensional Printing Spine Model in Severe Spine Deformity Correction Surgery

STUDY DESIGN

Retrospective case-control study.

OBJECTIVE

We aimed to evaluate the value of 3-dimensional printing (3DP) spine model in the surgical treatment of severe spinal deformity since the prosperous development of 3DP technology.

METHODS

Severe scoliosis or hyper-kyphosis patients underwent posterior fixation and fusion surgery using the 3DP spine models were reviewed (3DP group). Spinal deformity surgeries operated by free-hand screw implantation during the same period were selected as the control group after propensity score matching (PSM). The correction rate, pedicle screw accuracy, and complications were analyzed. Class A and B screws were defined as accurate according to Gertzbein and Robbins criteria.

RESULTS

35 patients were enrolled in the 3DP group and 35 matched cases were included in the control group. The perioperative baseline data and deformity correction rate were similar between both groups (P > .05). However, the operation time and blood loss were significantly less in the 3DP group (296.14 ± 66.18 min vs. 329.43 ± 67.16 min, 711.43 ± 552.28 mL vs. 1322.29 ± 828.23 mL, P < .05). More three-column osteotomies (Grade 3-6) were performed in the 3DP group (30/35, 85.7% vs. 21/35, 60.0%. P = .016). The screw placement accuracy was significantly higher in the 3DP group (422/582, 72.51% vs. 397/575, 69.04%. P = .024). The screw misplacement related complication rate was significantly higher in the free-hand group (6/35 vs. 1/35, P = .046).

CONCLUSIONS

The study provided solid evidence that 3DP spine models can enhance surgeons' confidence in performing higher grade osteotomies and improve the safety and efficiency in severe spine deformity correction surgery. 3D printing technology has a good prospect in spinal deformity surgery.

3D bioprinting of gastrointestinal cancer models: A comprehensive review on processing, properties, and therapeutic implications

Gastrointestinal tract (GIT) malignancies are an important public health problem considering the increased incidence in recent years and the high morbidity and mortality associated with it. GIT malignancies constitute 26% of the global cancer incidence burden and 35% of all cancer-related deaths. Gastrointestinal cancers are complex and heterogenous diseases caused by the interplay of genetic and environmental factors. The tumor microenvironment (TME) of gastrointestinal tract carcinomas is dynamic and complex; it cannot be recapitulated in the basic two-dimensional cell culture systems. In contrast, three-dimensional (3D) in vitro models can mimic the TME more closely, enabling an improved understanding of the microenvironmental cues involved in the various stages of cancer initiation, progression, and metastasis. However, the heterogeneity of the TME is incompletely reproduced in these 3D culture models, as they fail to regulate the orientation and interaction of various cell types in a complex architecture. To emulate the TME, 3D bioprinting has emerged as a useful technique to engineer cancer tissue models. Bioprinted cancer tissue models can potentially recapitulate cancer pathology and increase drug resistance in an organ-mimicking 3D environment. In this review, we describe the 3D bioprinting methods, bioinks, characterization of 3D bioprinted constructs, and their application in developing gastrointestinal tumor models that integrate their microenvironment with different cell types and substrates, as well as bioprinting modalities and their application in therapy and drug screening. We review prominent studies on the 3D bioprinted esophageal, hepatobiliary, and colorectal cancer models. In addition, this review provides a comprehensive understanding of the cancer microenvironment in printed tumor models, highlights current challenges with respect to their clinical translation, and summarizes future perspectives.

A systematic review of follow-up results of additively manufactured customized implants for the pelvic area

INTRODUCTION

While 3D printing of bone models for preoperative planning or customized surgical templating has been successfully implemented, the use of patient-specific additively manufactured (AM) implants is a newer application not yet well established. To fully evaluate the advantages and shortcomings of such implants, their follow-up results need to be evaluated.

AREA COVERED

This systematic review provides a survey of the reported follow-ups on AM implants used for oncologic reconstruction, total hip arthroplasty both primary and revision, acetabular fracture, and sacrum defects.

EXPERT OPINION

The review shows that Titanium alloy (Ti4AL6V) is the most common type of material system used due to its excellent biomechanical properties. Electron beam melting (EBM) is the predominant AM process for manufacturing implants. In almost all cases, porosity at the contact surface is implemented through the design of lattice or porous structures to enhance osseointegration. The follow-up evaluations show promising results, with only a small number of patients suffering from aseptic loosening, wear, or malalignment. The longest reported follow-up length was 120 months for acetabular cages and 96 months for acetabular cups. The AM implants have proven to serve as an excellent option to restore premorbid skeletal anatomy of the pelvis.

Exploring the value of three-dimensional printing and virtualization in paediatric healthcare: A multi-case quality improvement study

Background

Three-dimensional printing is being utilized in clinical medicine to support activities including surgical planning, education, and medical device fabrication. To better understand the impacts of this technology, a survey was implemented with radiologists, specialist physicians, and surgeons at a tertiary care hospital in Canada, examining multidimensional value and considerations for uptake.

Objectives

To examine how three-dimensional printing can be integrated into the paediatric context and highlight areas of impact and value to the healthcare system using Kirkpatrick's Model. Secondarily, to explore the perspective of clinicians utilizing three-dimensional models and how they make decisions about whether or not to use the technology in patient care.

Methods

A post-case survey. Descriptive statistics are provided for Likert-style questions, and a thematic analysis was conducted to identify common patterns in open-ended responses.

Results

In total, 37 respondents were surveyed across 19 clinical cases, providing their perspectives on model reaction, learning, behaviour, and results. We found surgeons and specialists to consider the models more beneficial than radiologists. Results further showed that the models were more helpful when used to assess the likelihood of success or failure of clinical management strategies, and for intraoperative orientation. We demonstrate that three-dimensional printed models could improve perioperative metrics, including a reduction in operating room time, but with a reciprocal effect on pre-procedural planning time. Clinicians who shared the models with patients and families thought it increased understanding of the disease and surgical procedure, and had no effect on their consultation time.

Conclusions

Three-dimensional printing and virtualization were used in preoperative planning and for communication among the clinical care team, trainees, patients, and families. Three-dimensional models provide multidimensional value to clinical teams, patients, and the health system. Further investigation is warranted to assess value in other clinical areas, across disciplines, and from a health economics and outcomes perspective.

3D bioprinting and the revolution in experimental cancer model systems-A review of developing new models and experiences with in vitro 3D bioprinted breast cancer tissue-mimetic structures

Growing evidence propagates those alternative technologies (relevant human cell-based-e.g., organ-on-chips or biofabricated models-or artificial intelligence-combined technologies) that could help in vitro test and predict human response and toxicity in medical research more accurately. In vitro disease model developments have great efforts to create and serve the need of reducing and replacing animal experiments and establishing human cell-based in vitro test systems for research use, innovations, and drug tests. We need human cell-based test systems for disease models and experimental cancer research; therefore, in vitro three-dimensional (3D) models have a renaissance, and the rediscovery and development of these technologies are growing ever faster. This recent paper summarises the early history of cell biology/cellular pathology, cell-, tissue culturing, and cancer research models. In addition, we highlight the results of the increasing use of 3D model systems and the 3D bioprinted/biofabricated model developments. Moreover, we present our newly established 3D bioprinted luminal B type breast cancer model system, and the advantages of in vitro 3D models, especially the bioprinted ones. Based on our results and the reviewed developments of in vitro breast cancer models, the heterogeneity and the real in vivo situation of cancer tissues can be represented better by using 3D bioprinted, biofabricated models. However, standardising the 3D bioprinting methods is necessary for future applications in different high-throughput drug tests and patient-derived tumour models. Applying these standardised new models can lead to the point that cancer drug developments will be more successful, efficient, and consequently cost-effective in the near future.

Utility and Costs During the Initial Year of 3D Printing in an Academic Hospital

OBJECTIVE

There is a paucity of utility and cost data regarding the launch of 3D printing in a hospital. The objective of this project is to benchmark utility and costs for radiology-based in-hospital 3D printing of anatomic models in a single, adult academic hospital.

METHODS

All consecutive patients for whom 3D printed anatomic models were requested during the first year of operation were included. All 3D printing activities were documented by the 3D printing faculty and referring specialists. For patients who underwent a procedure informed by 3D printing, clinical utility was determined by the specialist who requested the model. A new metric for utility termed Anatomic Model Utility Points with range 0 (lowest utility) to 500 (highest utility) was derived from the specialist answers to Likert statements. Costs expressed in United States dollars were tallied from all 3D printing human resources and overhead. Total costs, focused costs, and outsourced costs were estimated. The specialist estimated the procedure room time saved from the 3D printed model. The time saved was converted to dollars using hospital procedure room costs.

RESULTS

The 78 patients referred for 3D printed anatomic models included 11 clinical indications. For the 68 patients who had a procedure, the anatomic model utility points had an overall mean (SD) of 312 (57) per patient (range, 200-450 points). The total operation cost was $213,450. The total cost, focused costs, and outsourced costs were $2,737, $2,180, and $2,467 per model, respectively. Estimated procedure time saved had a mean (SD) of 29.9 (12.1) min (range, 0-60 min). The hospital procedure room cost per minute was $97 (theoretical $2,900 per patient saved with model).

DISCUSSION

Utility and cost benchmarks for anatomic models 3D printed in a hospital can inform health care budgets. Realizing pecuniary benefit from the procedure time saved requires future research.

3D Printing in a hospital: Centralized clinical implementation and applications for comprehensive care

This educational article discusses the use of 3D printing or additive manufacturing in hospitals, not just for rapid prototyping but also for creating end-use products, such as clinical, diagnostic, and educational tools. The flexibility of 3D printing is valuable for creating patient-specific medical devices, custom surgical tools, anatomical models, implants, research tools and on-demand parts, among others. The advantages of and requirements for implementing a clinical 3D printing service in a hospital environment are discussed, including centralized 3D printing management, technology, example use cases, and considerations for implementation. The article provides an overview for other institutions to reference in setting up or organizing their clinical 3D printing services and is applicable to general hospitals or various sub-specialty practices.

Zygomatic implant analogue simulation surgery and stereolithographic 3D models

This short communication will share the author's experience and protocols using stereolithographic (SLA) models to simulate zygomatic implant surgery.

Properties and Implementation of 3-Dimensionally Printed Models in Spine Surgery: A Mixed-Methods Review With Meta-Analysis

OBJECTIVE

Spine surgery addresses a wide range of spinal pathologies. Potential applications of 3-dimensional (3D) printed in spine surgery are broad, encompassing education, planning, and simulation. The objective of this study was to explore how 3D-printed spine models are implemented in spine surgery and their clinical applications.

METHODS

Methods were combined to create a scoping review with meta-analyses. PubMed, EMBASE, the Cochrane Library, and Scopus databases were searched from 2011 to 7 September 2021. Results were screened independently by 2 reviewers. Studies utilizing 3D-printed spine models in spine surgery were included. Articles describing drill guides, implants, or nonoriginal research were excluded. Data were extracted according to reporting guidelines in relation to study information, use of model, 3D printer and printing material, design features of the model, and clinical use/patient-related outcomes. Meta-analyses were performed using random-effects models.

RESULTS

Forty articles were included in the review, 3 of which were included in the meta-analysis. Primary use of the spine models included preoperative planning, education, and simulation. Six printing technologies were utilized. A range of substrates were used to recreate the spine and regional pathology. Models used for preoperative and intraoperative planning showed reductions in key surgical performance indicators. Generally, feedback for the tactility, utility, and education use of models was favorable.

CONCLUSIONS

Replicating realistic spine models for operative planning, education, and training is invaluable in a subspeciality where mistakes can have devastating repercussions. Future study should evaluate the cost-effectiveness and the impact spine models have of spine surgery outcomes.

Research landscape on 3D printing applications in healthcare within Southeast Asian countries: a systematic scoping review protocol

INTRODUCTION

Three-dimensional (3D) printing plays a significant role as a promising technological advancement in modern healthcare settings. 3D printing has been incorporated by many sectors worldwide including in Southeast Asian countries. However, there is a paucity of research, especially in the healthcare pertaining to 3D printing activity in the Southeast Asian region. Thus, a scoping review is conducted to gain insight into 3D printing healthcare research landscape in the Southeast Asian region.

METHODS AND ANALYSIS

The methodology draws on Arksey and O'Malley's seminal framework for the scoping review. The literature search will be conducted by using keywords to find suitable published literature. The existing literature will be searched using selected electronic databases such as PubMed/MEDLINE, CINAHL, Scopus, ProQuest and Web of Science from the years 2011 and 2021. The selected publications will focus on 10 Southeast Asian countries: Malaysia, Indonesia, Singapore, Thailand, Brunei, Philippines, Laos, Vietnam, Cambodia and Myanmar. Two reviewers will be performing title and abstract screening for the criteria of each publication, in which they will be working independently of each other. The included publication will undergo a full-text review and references cited will be examined for relevance using the same inclusion criteria. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram will guide throughout the process. Data will be extracted, analysed and charted within each category from the selected publications for each Southeast Asian country.

ETHICS AND DISSEMINATION

The results of this scoping review will illustrate an overview of the 3D printing healthcare research in the Southeast Asian context, which can be a guide for the advancement of 3D printing that can be accentuated in future research. The results will undergo dissemination which will be submitted for publication in a scientific journal.

Feasibility of Customized Pillboxes to Enhance Medication Adherence: A Randomized Controlled Trial

OBJECTIVE

To test the (1) feasibility of an assistive technology based pillbox intervention on medication adherence; (2) feasibility of trial procedures; and (3) preliminary effectiveness of the pillbox intervention on medication adherence.

DESIGN

A single-blinded randomized controlled clinical trial was conducted during 2-4 weeks.

SETTING

Researchers recruited a convenience sample to participate in this university laboratory-based study.

PARTICIPANTS

English-speaking consumers of 2 or more daily medications (N=15) participated in the study. Individuals with cognitive impairment or who did not manage their own medications were excluded.

INTERVENTIONS

Participants were randomized to 1 of 3 pillbox interventions: (1) standard-of-care pillbox; (2) customized off-the-shelf pillbox; or (3) customized 3-dimensional (3D) printed pillbox.

MAIN OUTCOME MEASURES

Outcome measures were divided among the 3 goals of the study. In addition to feasibility metrics, the Adherence to Refills and Medications Scale was used to measure the primary outcome measure, medication adherence. The Quebec User Evaluation of Satisfaction with Assistive Technology was used to measure pillbox satisfaction.

RESULTS

Researchers successfully administered 6 standard-of-care, 5 custom off-the-shelf, and 4 custom 3D printed pillboxes. Compared with the standard-of-care pillboxes, customized 3D printed pillboxes had large (d=1.04) and customized off-the-shelf pillboxes had medium (d=0.67) effects on medication adherence.

CONCLUSIONS

Prescription of customized pillboxes using a manualized and novel assistive technology approach that leverages 3D printing is feasible.

Comparison of 2 open-sourced 3-dimensional modeling techniques for orthopaedic application

Objectives: Although 3-dimensional (3D) printing is becoming more widely adopted for clinical applications, it is yet to be accepted as part of standard practice. One of the key applications of this technology is orthopaedic surgical planning for urgent trauma cases. Anatomically accurate replicas of patients' fracture models can be produced to guide intervention. These high-quality models facilitate the design and printing of patient-specific implants and surgical devices. Therefore, a fast and accurate workflow will help orthopaedic surgeons to generate high-quality 3D printable models of complex fractures. Currently, there is a lack of access to an uncomplicated and inexpensive workflow. Methods: Using patient DICOM data sets (n = 13), we devised a novel, simple, open-source, and rapid modeling process using Drishti software and compared its efficacy and data storage with the 3D Slicer image computing platform. We imported the computed tomography image directory acquired from patients into the software to isolate the model of bone surface from surrounding soft tissue using the minimum functions. One pelvic fracture case was further integrated into the customized implant design practice to demonstrate the compatibility of the 3D models generated from Drishti. Results: The data sizes of the generated 3D models and the processing files that represent the original DICOM of Drishti are on average 27% and 12% smaller than that of 3D Slicer, respectively (both P < 0.05). The time frame needed to reach the stage of viewing the 3D bone model and the exporting of the data of Drishti is 39% and 38% faster than that of 3D Slicer, respectively (both P < 0.05). We also constructed a virtual model using third-party software to trial the implant design. Conclusions: Drishti is more suitable for urgent trauma cases that require fast and efficient 3D bone reconstruction with less hardware requirement. 3D Slicer performs better at quantitative preoperative planning and multilayer segmentation. Both software platforms are compatible with third-party programs used to produce customized implants that could be useful for surgical training. Level of Evidence: Level V.

3D printing in fracture treatment : Current practice and best practice consensus

The use of 3D printing in orthopedic trauma is supported by clinical evidence. Existing computed tomography (CT) data are exploited for better stereotactic identification of morphological features of the fracture and enhanced surgical planning. Due to complex logistic, technical and resource constraints, deployment of 3D printing is not straightforward from the hospital management perspective. As a result not all trauma surgeons are able to confidently integrate 3D printing into the daily practice. We carried out an expert panel survey on six trauma units which utilized 3D printing routinely. The most frequent indications are acetabular and articular fractures and malalignments. Infrastructure and manpower structure varied between units. The installation of industrial grade machines and dedicated software as well as the use of trained personnel can enhance the capacity and reliability of fracture treatment. Setting up interdisciplinary jointly used 3d printing departments with sound financial and management structures may improve sustainability. The sometimes substantial logistic and technical barriers which impede the rapid delivery of 3D printed models are discussed.

Point-of-Care Virtual Surgical Planning and 3D Printing in Oral and Cranio-Maxillofacial Surgery: A Narrative Review

This paper provides an overview on the use of virtual surgical planning (VSP) and point-of-care 3D printing (POC 3DP) in oral and cranio-maxillofacial (CMF) surgery based on a literature review. The authors searched PubMed, Web of Science, and Embase to find papers published between January 2015 and February 2022 in English, which describe human applications of POC 3DP in CMF surgery, resulting in 63 articles being included. The main review findings were as follows: most used clinical applications were anatomical models and cutting guides; production took place in-house or as "in-house-outsourced" workflows; the surgeon alone was involved in POC 3DP in 36 papers; the use of free versus paid planning software was balanced (50.72% vs. 49.27%); average planning time was 4.44 h; overall operating time decreased and outcomes were favorable, though evidence-based studies were limited; and finally, the heterogenous cost reports made a comprehensive financial analysis difficult. Overall, the development of in-house 3D printed devices supports CMF surgery, and encouraging results indicate that the technology has matured considerably.

DAR 16-II Primes Endothelial Cells for Angiogenesis Improving Bone Ingrowth in 3D-Printed BCP Scaffolds and Regeneration of Critically Sized Bone Defects

Bone is a highly vascularized tissue and relies on the angiogenesis and response of cells in the immediate environmental niche at the defect site for regeneration. Hence, the ability to control angiogenesis and cellular responses during osteogenesis has important implications in tissue-engineered strategies. Self-assembling ionic-complementary peptides have received much interest as they mimic the natural extracellular matrix. Three-dimensional (3D)-printed biphasic calcium phosphate (BCP) scaffolds coated with self-assembling DAR 16-II peptide provide a support template with the ability to recruit and enhance the adhesion of cells. In vitro studies demonstrated prompt the adhesion of both human umbilical vein endothelial cells (HUVEC) and human mesenchymal stem cells (hMSC), favoring endothelial cell activation toward an angiogenic phenotype. The SEM-EDS and protein micro bicinchoninic acid (BCA) assays demonstrated the efficacy of the coating. Whole proteomic analysis of DAR 16-II-treated HUVECs demonstrated the upregulation of proteins involved in cell adhesion (HABP2), migration (AMOTL1), cytoskeletal re-arrangement (SHC1, TMOD2), immuno-modulation (AMBP, MIF), and morphogenesis (COL4A1). In vivo studies using DAR-16-II-coated scaffolds provided an architectural template, promoting cell colonization, osteogenesis, and angiogenesis. In conclusion, DAR 16-II acts as a proactive angiogenic factor when adsorbed onto BCP scaffolds and provides a simple and effective functionalization step to facilitate the translation of tailored 3D-printed BCP scaffolds for clinical applications.

3D printed fracture reduction guides planned and printed at the point of care show high accuracy - a porcine feasibility study

Purpose

After surgical treatment of comminuted diaphyseal femoral and tibial fractures, relevant malalignment, especially rotational errors occur in up to 40–50%. This either results in a poor clinical outcome or requires revision surgery. This study aims to evaluate the accuracy of reduction if surgery is supported by 3D guides planned and printed at the point of care.

Methods

Ten porcine legs underwent computed tomography (CT) and 3D models of femur and tibia were built. Reduction guides were virtually constructed and fitted to the proximal and distal metaphysis. The guides were 3D printed using medically approved resin. Femoral and tibial comminuted diaphyseal fractures were simulated and subsequently reduced using the 3D guides. Postoperative 3D bone models were reconstructed to compare the accuracy to the preoperative planning.

Results

Femoral reduction showed a mean deviation ± SD from the plan of 1.0 mm ± 0.9 mm for length, 0.9° ± 0.7° for varus/valgus, 1.2° ± 0.9° for procurvatum/recurvatum and 2.0° ± 1.7° for rotation. Analysis of the tibial reduction revealed a mean deviation ± SD of 2.4 mm ± 1.6 mm for length, 1.0° ± 0.6° for varus/valgus, 1.3° ± 1.4° for procurvatum/recurvatum and 2.9° ± 2.2° for rotation.

Conclusions

This study shows high accuracy of reduction with 3D guides planned and printed at the point of care. Applied to a clinical setting, this technique has the potential to avoid malreduction and consecutive revision surgery in comminuted diaphyseal fractures.

Level of Evidence

Basic Science.

3D Bioprinted Chitosan-Based Hydrogel Scaffolds in Tissue Engineering and Localised Drug Delivery

Bioprinting is an emerging technology with various applications in developing functional tissue constructs for the replacement of harmed or damaged tissues and simultaneously controlled drug delivery systems (DDSs) for the administration of several active substances, such as growth factors, proteins, and drug molecules. It is a novel approach that provides high reproducibility and precise control over the fabricated constructs in an automated way. An ideal bioink should possess proper mechanical, rheological, and biological properties essential to ensure proper function. Chitosan is a promising natural-derived polysaccharide to be used as ink because of its attractive properties, such as biodegradability, biocompatibility, low cost, and non-immunogenicity. This review focuses on 3D bioprinting technology for the preparation of chitosan-based hydrogel scaffolds for the regeneration of tissues delivering either cells or active substances to promote restoration.

Implementation of an In-House 3D Manufacturing Unit in a Public Hospital’s Radiology Department

Objective: Three-dimensional printing has become a leading manufacturing technique in healthcare in recent years. Doubts in published studies regarding the methodological rigor and cost-effectiveness and stricter regulations have stopped the transfer of this technology in many healthcare organizations. The aim of this study was the evaluation and implementation of a 3D printing technology service in a radiology department. Methods: This work describes a methodology to implement a 3D printing service in a radiology department of a Spanish public hospital, considering leadership, training, workflow, clinical integration, quality processes and usability. Results: The results correspond to a 6-year period, during which we performed up to 352 cases, requested by 85 different clinicians. The training, quality control and processes required for the scaled implementation of an in-house 3D printing service are also reported. Conclusions: Despite the maturity of the technology and its impact on the clinic, it is necessary to establish new workflows to correctly implement them into the strategy of the health organization, adjusting it to the needs of clinicians and to their specific resources. Significance: This work allows hospitals to bridge the gap between research and 3D printing, setting up its transfer to clinical practice and using implementation methodology for decision support.

Guide for starting or optimizing a 3D printing clinical service

Three-dimensional (3D) printing has applications in many fields and has gained substantial traction in medicine as a modality to transform two-dimensional scans into three-dimensional renderings. Patient-specific 3D printed models have direct patient care uses in surgical and procedural specialties, allowing for increased precision and accuracy in developing treatment plans and guiding surgeries. Medical applications include surgical planning, surgical guides, patient and trainee education, and implant fabrication. 3D printing workflow for a laboratory or clinical service that produces anatomic models and guides includes optimizing imaging acquisition and post-processing, segmenting the imaging, and printing the model. Quality assurance considerations include supervising medical imaging expert radiologists' guidance and self-implementing in-house quality control programs. The purpose of this review is to provide a workflow and guide for starting or optimizing laboratories and clinical services that 3D-print anatomic models or guides for clinical use.

The sustainability of emerging technologies for use in pharmaceutical manufacturing

INTRODUCTION

Sustainability within the pharmaceutical industry is becoming a focal point for many companies, to improve the longevity and social perception of the industry. Both additive manufacturing (AM) and microfluidics (MFs) are continuously progressing, so are far from their optimization in terms of sustainability; hence, it is the aim of this review to highlight potential gaps alongside their beneficial features. Discussed throughout this review also will be an in-depth discussion on the environmental, legal, economic, and social particulars relating to these emerging technologies.

AREAS COVERED

Additive manufacturing (AM) and microfluidics (MFs) are discussed in depth within this review, drawing from up-to-date literature relating to sustainability and circular economies. This applies to both technologies being utilized for therapeutic and analytical purposes within the pharmaceutical industry.

EXPERT OPINION

It is the role of emerging technologies to be at the forefront of promoting a sustainable message by delivering plausible environmental standards whilst maintaining efficacy and economic viability. AM processes are highly customizable, allowing for their optimization in terms of sustainability, from reducing printing time to reducing material usage by removing supports. MFs too are supporting sustainability via reduced material wastage and providing a sustainable means for point of care analysis.

Mechanical response assessment of antibacterial PA12/TiO2 3D printed parts: parameters optimization through artificial neural networks modeling

This study investigates the mechanical response of antibacterial PA12/TiO2 nanocomposite 3D printed specimens by varying the TiO2 loading in the filament, raster deposition angle, and nozzle temperature. The prediction of the antibacterial and mechanical performance of such nanocomposites is a challenging field, especially nowadays with the covid-19 pandemic dilemma. The experimental work in this study utilizes a fully factorial design approach to analyze the effect of three parameters on the mechanical response of 3D printed components. Therefore, all combinations of these three parameters were tested, resulting in twenty-seven independent experiments, in which each combination was repeated three times (a total of eighty-one experiments). The antibacterial performance of the fabricated PA12/TiO2 nanocomposite materials was confirmed, and regression and arithmetic artificial neural network (ANN) models were developed and validated for mechanical response prediction. The analysis of the results showed that an increase in the TiO2% loading decreased the mechanical responses but increased the antibacterial performance of the nanocomposites. In addition, higher nozzle temperatures and zero deposition angles optimize the mechanical performance of all TiO2% nanocomposites. Independent experiments evaluated the proposed models with mean absolute percentage errors (MAPE) similar to the ANN models. These findings and the interaction charts show a strong interaction between the studied parameters. Therefore, the authors propose the improvement of predictions by utilizing artificial neural network models and genetic algorithms as future work and the spreading of the experimental area with extra variable parameters and levels.

3D Printing and Virtual Surgical Planning in Oral and Maxillofacial Surgery

Compared to traditional manufacturing methods, additive manufacturing and 3D printing stand out in their ability to rapidly fabricate complex structures and precise geometries. The growing need for products with different designs, purposes and materials led to the development of 3D printing, serving as a driving force for the 4th industrial revolution and digitization of manufacturing. 3D printing has had a global impact on healthcare, with patient-customized implants now replacing generic implantable medical devices. This revolution has had a particularly significant impact on oral and maxillofacial surgery, where surgeons rely on precision medicine in everyday practice. Trauma, orthognathic surgery and total joint replacement therapy represent several examples of treatments improved by 3D technologies. The widespread and rapid implementation of 3D technologies in clinical settings has led to the development of point-of-care treatment facilities with in-house infrastructure, enabling surgical teams to participate in the 3D design and manufacturing of devices. 3D technologies have had a tremendous impact on clinical outcomes and on the way clinicians approach treatment planning. The current review offers our perspective on the implementation of 3D-based technologies in the field of oral and maxillofacial surgery, while indicating major clinical applications. Moreover, the current report outlines the 3D printing point-of-care concept in the field of oral and maxillofacial surgery.

3D-Printed Patient-Specific Casts for the Distal Radius in Children: Outcome and Pre-Market Survey

Background: Orthopaedic and Trauma surgery is expected to undergo profound transformation as a result of the adoption of 3D technology. Among the various applications, patient specific manufacturing of splints and casts would appear to be, particularly in children, an interesting implementation. This study aims to assess the safety of patient specific 3D casts obtained with a newly developed 3D-scanning devise in a small case series. We therefore conducted a clinical outcome and pre-marketing study in 10 consecutive patients with distal radius fractures treated at an Academic Level I Pediatric Trauma Center. After the application of the 3D cast, patients underwent three consecutive evaluations in the following 21 days. The main outcome measurements were: pain, skin lesions and general comfort, and acceptance of the cast. The three domains were measured with the Visual Analogue Scale (VAS), the NPUAP/EPUAP classification and the Positive affect-Negative affect Scale for Children (PANAS-C), the Self-Assessment Manikin (SAM) clinical psychology tests and a Likert-type five item questionnaire, respectively. A final mechanical analysis of the cast was carried out to confirm product integrity. Results: The results obtained were consistently positive in the investigated domains of general comfort, efficacy of contention and mechanical integrity of the 3D-printed cast as well as in the practicability of the supply chain. Conclusions: This study provides Level IV evidence that patient specific 3D printed casts obtained with a specifically designed software were safe in the management of “buckle” fractures of the distal radius in children. These results encourage to extend the technology to the treatment of more demanding fractures.

Current Advances in 3D Bioprinting for Cancer Modeling and Personalized Medicine

Tumor cells evolve in a complex and heterogeneous environment composed of different cell types and an extracellular matrix. Current 2D culture methods are very limited in their ability to mimic the cancer cell environment. In recent years, various 3D models of cancer cells have been developed, notably in the form of spheroids/organoids, using scaffold or cancer-on-chip devices. However, these models have the disadvantage of not being able to precisely control the organization of multiple cell types in complex architecture and are sometimes not very reproducible in their production, and this is especially true for spheroids. Three-dimensional bioprinting can produce complex, multi-cellular, and reproducible constructs in which the matrix composition and rigidity can be adapted locally or globally to the tumor model studied. For these reasons, 3D bioprinting seems to be the technique of choice to mimic the tumor microenvironment in vivo as closely as possible. In this review, we discuss different 3D-bioprinting technologies, including bioinks and crosslinkers that can be used for in vitro cancer models and the techniques used to study cells grown in hydrogels; finally, we provide some applications of bioprinted cancer models.

Establishing 3D Printing at the Point of Care: Basic Principles and Tools for Success

As the medical applications of three-dimensional (3D) printing increase, so does the number of health care organizations in which adoption or expansion of 3D printing facilities is under consideration. With recent advancements in 3D printing technology, medical practitioners have embraced this powerful tool to help them to deliver high-quality patient care, with a focus on sustainability. The use of 3D printing in the hospital or clinic at the point of care (POC) has profound potential, but its adoption is not without unanticipated challenges and considerations. The authors provide the basic principles and considerations for building the infrastructure to support 3D printing inside the hospital. This process includes building a business case; determining the requirements for facilities, space, and staff; designing a digital workflow; and considering how electronic health records may have a role in the future. The authors also discuss the supported applications and benefits of medical 3D printing and briefly highlight quality and regulatory considerations. The information presented is meant to be a practical guide to assist radiology departments in exploring the possibilities of POC 3D printing and expanding it from a niche application to a fixture of clinical care. An invited commentary by Ballard is available online. ^©RSNA, 2022.

Facilitating the Adoption and Evolution of Digital Technologies Through Re-conceptualization

Background

The NHS has been making steps toward greater efficiency and cutting costs to maintain quality of care despite constraints, but without innovation the NHS will not be able to meet its increasing financial demands. The purpose of this article is to analyse a single potentially transformative technology's path of adoption in the NHS [3D printing (3DP)].

Methods

Analysis of 3DP and its current value propositions. Re-conceptualization of the technology to gain insights into these value propositions and identify the capabilities it may provide. Analysis of previous business models to identify where this value is not fully captured and development of a new business model, followed by exploration of benefits and potential limitations of this new model.

Results

3D printing applications can be broadly categorized into anatomical modeling, implants, and tools. Conceptualizing 3D imaging using the layered architecture model suggests the potential of 3DP to evolve the current imaging and modeling infrastructure of the NHS, and as such should be adopted to facilitate this potential.

Conclusion

3D printing is an innovation with large potential for generativity, and it is important that it is integrated at a level that could both stimulate and communicate its benefits. Re-conceptualization identified a backbone within the NHS that could facilitate it as a point of entry, and the most successful installations have been through this channel. However, progress on the frontier is currently limited by both physical and organizational boundaries, the resolution of which is paramount for the current and future success of this technology.

Additive Manufacturing of a Miniature Functional Trocar for Eye Surgery

Stereolithography is emerging as a promising additive manufacturing technology for a range of applications in the medical domain. However, for miniature, medical devices such as those used in ophthalmic surgery, a number of production challenges arise due to the small size of the components. In this work, we investigate the challenges of creating sub-millimeter features for a miniature, functional trocar using Stereolithography. The trocar cannula system is used in eye surgery to facilitate a passage for other instruments. A standard trocar consists of a hollow cannula and a flexible check valve. The research was performed in two stages: in the first stage we investigated the effect of different materials and print settings on the current design of the cannula and the valve separately, and in the second stage we used these findings to optimize the design and production process. After the first investigation, it became apparent that even though the dimensions of the trocar are within the feature size range of Stereolithography, all hollow features tended to fuse shut during printing. This effect appeared regardless of the materials or print settings, and can be attributed to refraction of the laser source. In order to circumvent this, we identified two potential strategies: (1) increasing the negative space surrounding features; and (2) decreasing the surface area per layer. By applying these strategies, we tested a new design for the cannula and valve and managed to 3D print a functional trocar, which was tested in an artificial eye. The design of the 3D printed trocar allows for further personalization depending on the specific requirements of both patient and surgeon. The proposed strategies can be applied to different applications to create miniature features using Stereolithography.

The cutting edge of customized surgery: 3D-printed models for patient-specific interventions in otology and auricular management-a systematic review

PURPOSE

3D-printing (three-dimensional printing) is an emerging technology with promising applications for patient-specific interventions. Nonetheless, knowledge on the clinical applicability of 3D-printing in otology and research on its use remains scattered. Understanding these new treatment options is a prerequisite for clinical implementation, which could improve patient outcomes. This review aims to explore current applications of 3D-printed patient-specific otologic interventions, including state of the evidence, strengths, limitations, and future possibilities.

METHODS

Following the PRISMA statement, relevant studies were identified through Pubmed, EMBASE, the Cochrane Library, and Web of Science. Data on the manufacturing process and interventions were extracted by two reviewers. Study quality was assessed using Joanna Briggs Institute's critical appraisal tools.

RESULTS

Screening yielded 590 studies; 63 were found eligible and included for analysis. 3D-printed models were used as guides, templates, implants, and devices. Outer ear interventions comprised 73% of the studies. Overall, optimistic sentiments on 3D-printed models were reported, including increased surgical precision/confidence, faster manufacturing/operation time, and reduced costs/complications. Nevertheless, study quality was low as most studies failed to use relevant objective outcomes, compare new interventions with conventional treatment, and sufficiently describe manufacturing.

CONCLUSION

Several clinical interventions using patient-specific 3D-printing in otology are considered promising. However, it remains unclear whether these interventions actually improve patient outcomes due to lack of comparison with conventional methods and low levels of evidence. Further, the reproducibility of the 3D-printed interventions is compromised by insufficient reporting. Future efforts should focus on objective, comparative outcomes evaluated in large-scale studies.

Design, inverted vat photopolymerization 3D printing, and initial characterization of a miniature force sensor for localized in vivo tissue measurements

Background

Tissue healthiness could be assessed by evaluating its viscoelastic properties through localized contact reaction force measurements to obtain quantitative time history information. To evaluate these properties for hard to reach and confined areas of the human body, miniature force sensors with size constraints and appropriate load capabilities are needed. This research article reports on the design, fabrication, integration, characterization, and in vivo experimentation of a uniaxial miniature force sensor on a human forearm.

Methods

The strain gauge based sensor components were designed to meet dimensional constraints (diameter ≤3.5mm), safety factor (≥3) and performance specifications (maximum applied load, resolution, sensitivity, and accuracy). The sensing element was fabricated using traditional machining. Inverted vat photopolymerization technology was used to prototype complex components on a Form3 printer; micro-component orientation for fabrication challenges were overcome through experimentation. The sensor performance was characterized using dead weights and a LabVIEW based custom developed data acquisition system. The operational performance was evaluated by in vivo measurements on a human forearm; the relaxation data were used to calculate the Voigt model viscoelastic coefficient.

Results

The three dimensional (3D) printed components exhibited good dimensional accuracy (maximum deviation of 183μm). The assembled sensor exhibited linear behavior (regression coefficient of R²=0.999) and met desired performance specifications of 3.4 safety factor, 1.2N load capacity, 18mN resolution, and 3.13% accuracy. The in vivo experimentally obtained relaxation data were analyzed using the Voigt model yielding a viscoelastic coefficient τ=12.38sec and a curve-fit regression coefficient of R²=0.992.

Conclusions

This research presented the successful design, use of 3D printing for component fabrication, integration, characterization, and analysis of initial in vivo collected measurements with excellent performance for a miniature force sensor for the assessment of tissue viscoelastic properties. Through this research certain limitations were identified, however the initial sensor performance was promising and encouraging to continue the work to improve the sensor. This micro-force sensor could be used to obtain tissue quantitative data to assess tissue healthiness for medical care over extended time periods.