Three-dimensional Printing in Orthopaedic Surgery: Current Applications and Future Developments

Three-dimensional printed titanium pseudo-prosthesis for the treatment of a tumoral bone defect

Additive manufacturing also known as three-dimensional printing (3D printing), provided the ability to produce precise three-dimensional structures, representing a rapidly growing field in Orthopaedics. Its clinical value has been attributed to the ability to create complex three dimensional objects with relative ease and at low cost. However, the available evidence regarding its applications in trauma was heterogeneous. This narrative review aimed to analyze the clinical applications of 3D printing in traumatology. Additionally, the research gaps that emerged in our literature search were underscored. Four application domains were selected based on their prevalence in the screened literature and relative level of clinical implementation within orthopaedic traumatology, including (1) 3D-printed anatomical models, (2) patient-specific surgical guides (PSSGs), (3) 3D-printed implants, and (4) temporary 3D-printed external fixation devices. 3D-printed anatomical models were found to help in reducing operative time, estimated blood loss, and the intraoperative radiation exposure. The use of PSSGs was shown to improve intraoperative accuracy and to provide a basis for consistent, accurate, and reproducible outcomes. However, their implementation was hindered by preparation time, the need for stable anatomical landmarks, and reduced accuracy due to potential soft-tissue injury and swelling. In contrast, 3D-printed implants and external fixation devices constituted promising but less extensively studied applications of 3D printing in trauma. The production of customized implants and external fixators, as suggested by the studies available, was deemed feasible, with comparable mechanical properties and significantly lower cost. Larger multicenter studies are required to support and validate these findings. Overall, based on the available evidence, 3D-printed anatomical models and patient-specific surgical guides demonstrate the highest level of clinical applicability, primarily in preoperative planning and intraoperative guidance.

The application of three-dimensional (3D) printing in medicine has increased rapidly in the last few years. Various new commercial 3D printers and 3D bioprinters are introduced into the current market. 3D printing scientific community has witnessed a rapid growth in the application of 3D printing for various medical needs. There has been a research advancement in 4D printing with a widened scope of 3D bioprinting. The growing demand for 3D printing and its use for commercial and industrial purposes in medical technology have facilitated the need for introduction of new international standards and regulations. The need for organ replacement has generated curiosity and competition among researchers to race for organ 3D printing, which can be identified with increased publications and patents that are filed in recent years. Hence, there is a need to update the readers with the latest information. The second edition of this chapter updates the contents of first section to fourth section with current information and some modified pictorial representations. New section describes the relevance of the new chapters added to this edition and updates the readers with insights on advancement of 3D printing in the last decade. Briefly, this chapter introduces the reader with a brief history of 3D printing in medical technology, components of 3D printing, 3D bioprinting, organ 3D bioprinting, advantages of 3D printing with current challenges and commercially available 3D printers in the current market. New sections introduced in this edition detail about the ASTM and ISO standards that are used for 3D printing in medicine, the regulatory framework with current challenges, ethical and social concerns with the current 3D printing scientific community, and the importance of intellectual property in safeguarding the interests of the innovators.

The advent of personalized bone prosthesis materials and their integration into orthopedic surgery has made a profound impact, primarily as a result of the incorporation of three-dimensional (3D) printing technology. By leveraging digital models and additive manufacturing techniques, 3D printing enables the creation of customized, high-precision bone implants tailored to address complex anatomical variabilities and challenging bone defects. In this review, we highlight the significant progress in utilizing 3D-printed prostheses across a wide range of orthopedic procedures, including pelvis, hip, knee, foot, ankle, spine surgeries, and bone tumor resections. The integration of 3D printing in preoperative planning, surgical navigation, and postoperative rehabilitation not only enhances treatment outcomes but also reduces surgical risks, accelerates recovery, and optimizes cost-effectiveness. Emphasizing the potential for personalized care and improved patient outcomes, this review underscores the pivotal role of 3D-printed bone prosthesis materials in advancing orthopedic practice towards precision, efficiency, and patient-centric solutions. The evolving landscape of 3D printing in orthopedic surgery holds promise for revolutionizing treatment approaches, enhancing surgical outcomes, and ultimately improving the quality of care for orthopedic patients.

Three-dimensional (3D) printing or Additive manufacturing has paved the way for developing and manufacturing pharmaceuticals in a personalized manner for patients with high volume and rare diseases. The traditional pharmaceutical manufacturing process involves the utilization of various excipients to facilitate the stages of blending, mixing, pressing, releasing, and packaging. In some cases, these excipients cause serious side effects to the patients. The 3D printing of pharmaceutical manufacturing avoids the need for excessive excipients. The two major components of a 3D printed tablet or dosage form are polymer matrix and drug component alone. Hence the usage of the 3D printed dosage forms for disease treatment will avoid unwanted side effects and provide higher therapeutic efficacy. With respect to the benefits of the 3D printed pharmaceuticals, the present review was constructed by discussing the role of 3D printing in producing formulations of various dosage forms such as fast and slow releasing, buccal delivery, and localized delivery. The dosage forms are polymeric tablets, nanoparticles, scaffolds, and films employed for treating different diseases.

Green 3D bioprinting of plant cells: A new scope for 3D bioprinting

Objective To explore the application value of three-dimensional (3D) printing in skull base tumor resection. Methods Fourteen patients accepted resection of skull base tumors in our hospital from May 2016 to November 2017 were chosen in our study; before surgery, solid models of the tumors, having bones of the skull base, tumor tissues and main blood supply arteries, were established by 3D printing; resection was simulated in these models and the surgical approaches and surgical methods were determined accordingly. The disease history, preoperative and postoperative imaging data were analyzed retrospectively. Results The mean time for making a solid model of the tumors was 18.5 h, and the cost was about 5,000 Yuan. Postoperative CT and MR imaging showed that total excision was achieved in 8 patients, subtotal excision was achieved in 5 patients, and one with tumor of the jugular foramen achieved total excision of the intracranial tumor and subtotal excision of the extracranial tumor. One patient had large hemispheric infarction after operation and decompressive craniectomy was performed; the other 13 patients recovered well without serious complications or death. Conclusion The 3D printing technique can assist the preoperative simulation and formulation of skull base tumor resection, and improve the efficiency and safety of the operation. Key words: Three-dimensional printing; Tumor of base of skull; Tumor resection

Three-dimensional (3D) printing is one of the most well-liked new innovative and promising manufacturing techniques, which has demonstrated tremendous potential for the creation of biostructures in tissue engineering, particularly for bones, orthopaedic tissues, and related organs. 3D printing for the medical industry was considered a lofty pipe dream. Time and money, though, made it a reality. Today's 3D printing technology has a significant possibility to assist pharmaceutical and medical corporations in developing more specialised pharmaceuticals, enabling the quick creation of medical implants, and transforming how doctors and surgeons approach surgical planning. In today's practise of precision medicine and for individualised therapies, patient-specific anatomical models that are 3D printed are becoming increasingly helpful tools. In contrast to the conventional use of 3D printing to create cell-free scaffolds, 3D bioprinting requires various technical methods, such as biomimicry, autonomous self-assembly, and mini-tissue building blocks, to create 3D structures with mechanical and biological properties suitable for the deposition of living cells and the restoration of tissue and organ function. Cells, bioinks, and bioprinters are all necessary components of the bioprinting process, and each one of them has biological, technological, ethical, and cost- and clinically-effectiveness-related issues. As a result, there are several difficulties in integrating 3D bioprinting into widespread clinical practise. Currently, there are multiple applications for 3D bioprinting such as in surgery, cardiovascular system, musculoskeletal and even in drug screening. All of which will be discussed in this review.

Chapter 2 - 3D printing and nanotechnology

The widespread application of additive manufacturing (AM) technologies, commonly known as three-dimensional (3D) printing, in industrial and home-business sectors, and the expected increase in the number of workers and consumers that use these devices, have raised concerns regarding the possible health implications of 3D printing emissions. To inform the risk assessment and management processes, this review evaluates available data concerning exposure assessment in AM workplaces and possible effects of 3D printing emissions on humans identified through in vivo and in vitro models in order to inform risk assessment and management processes. Peer-reviewed literature was identified in Pubmed, Scopus, and ISI Web of Science databases. The literature demonstrated that a significant fraction of the particles released during 3D printing could be in the ultrafine size range. Depending upon the additive material composition, increased levels of metals and volatile organic compounds could be detected during AM operations, compared with background levels. AM phases, specific job tasks performed, and preventive measures adopted may all affect exposure levels. Regarding possible health effects, printer emissions were preliminary reported to affect the respiratory system of involved workers. The limited number of workplace studies, together with the great variety of AM techniques and additive materials employed, limit generalizability of exposure features. Therefore, greater scientific efforts should be focused at understanding sources, magnitudes, and possible health effects of exposures to develop suitable processes for occupational risk assessment and management of AM technologies.

Three-dimensional (3D) printing allows for the design and printing of more complex designs than traditional manufacturing processes. For the manufacture of personalised medicines, such an advantage could enable the production of personalised drug products on demand. In this study, two types of extrusion-based 3D printing techniques, semi-solid syringe extrusion 3D printing and fused deposition modelling, were used to fabricate a combi-layer construct (combi-pill). Two model drugs, tranexamic acid (water soluble, rapid release) and indomethacin (poorly water-soluble, extended release), were printed with different geometries and materials compositions. Fourier transform infrared spectroscopy results showed that there were no interactions detected between drug-drug and drug-polymers. The printed combi-pills demonstrated excellent abrasion resisting properties in friability tests. The use of different functional excipients demonstrated significant impact on in vitro drug release of the model drugs incorporated in two 3D printed layers. Tranexamic acid and indomethacin were successfully 3D printed as a combi-pill with immediate-release and sustained-release profiles, respectively, to target quick anti-bleeding and prolonged anti-inflammation functions. For the first time, this paper systematically demonstrates the feasibility of coupling syringe-based extrusion 3D printing and fused deposition modelling as an innovative platform for various drug therapy productions, facilitating a new era of personalised combi-pills development.

4D printing: Pragmatic progression in biofabrication

The use of 3-dimensional (3D) printing in orthopedics is developing rapidly and impacting the areas of preoperative planning, surgical guides, and simulation. As this technology continues to improve, the greatest impact of 3D printing may be in low- and middle-income countries where surgical items are in short supply. This study investigated sterility of 3D-printed ankle fracture fixation plates and cortical screws. The hypothesis was that the process of heated extrusion in fused deposition modeling printing would create sterile prints in a timely fashion that would not require postproduction sterilization. A free computer-assisted design program was used to design the implant models. One control group and 8 study groups were printed. Print construct, orientation, size, and postproduction sterilization differed among the groups. Sterility was assessed using thioglycollate broth cultures at 24 hours, 48 hours, and 7 days. Positive growth was speciated for aerobic and anaerobic bacteria. Print time and failed prints were recorded. Control samples were 100% positive for bacterial growth. All test samples remained sterile at all time points (100%). Speciation of control samples was obtained, and Staphylococcus was the most common species. Print times varied; however, no print time exceeded 6.75 minutes. Eighteen prints (17%) failed in the printing process. These findings demonstrate an intrinsic sterilization process associated with fused deposition modeling 3D printing and indicate the feasibility of 3D-printed surgical implants and equipment for orthopedic applications. With future research, 3D-printed implants may be a treatment modality to assist orthopedic surgeons in low- and middle-income countries. [Orthopedics. 2020; 43(1): 46-51.].

Three-dimensional (3D) printing technology is characterized by "inside-out" stack manufacturing. Compared with conventional technologies, 3D printing has the advantage of personalization and precision. Therefore, the shape and internal structure of the scaffolds made by 3D printing technology are highly biomimetic. Besides, 3D bioprinting can precisely deposit the biomaterials, seeding cells and cytokines at the same time, which is a breakthrough in printing technique and material science. With the development of 3D printing, it will make great contributions to the reconstruction of vertebrae and intervertebral disc in the future.

Three-dimensional(3D) printing, a key technique of rapid prototyping (RP), is developing rapidly all over the world. As 3D printing has a significant advantage of personalized manufacturing, it has exerted a profound effect on medicine. The high demand for personalized manufacturing in the field of orthosis provides an excellent opportunity for widespread use of 3D printing technique. This review briefly introduces the principles and characteristics of different forming methods of 3D printing, the types and characteristics of 3D printing materials widely used at present, and classification and clinical application of orthoses. We also summarize the domestic and international research on and manufacture of orthoses using 3D printing techniques, and discuss current problems and future development of 3D printing techniques in orthosis. Key words: Orthopedic fixation devices; Rehabilitation; Review; 3D Printing; Additive manufacturing