Advantages and disadvantages of 3-dimensional printing in surgery: A systematic review

Logistics of Three-dimensional Printing: Primer for Radiologists

The Association of University Radiologists Radiology Research Alliance Task Force on three-dimensional (3D) printing presents a review of the logistic considerations for establishing a clinical service using this new technology, specifically focused on implications for radiology. Specific topics include printer selection for 3D printing, software selection, creating a 3D model for printing, providing a 3D printing service, research directions, and opportunities for radiologists to be involved in 3D printing. A thorough understanding of the technology and its capabilities is necessary as the field of 3D printing continues to grow. Radiologists are in the unique position to guide this emerging technology and its use in the clinical arena.

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

OBJECTIVE

To evaluate the clinical efficacy and effectiveness of using 3D printing to develop medical devices across all medical fields.

DESIGN

Systematic review compliant with Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

DATA SOURCES

PubMed, Web of Science, OVID, IEEE Xplore and Google Scholar.

METHODS

A double-blinded review method was used to select all abstracts up to January 2017 that reported on clinical trials of a three-dimensional (3D)-printed medical device. The studies were ranked according to their level of evidence, divided into medical fields based on the International Classification of Diseases chapter divisions and categorised into whether they were used for preoperative planning, aiding surgery or therapy. The Downs and Black Quality Index critical appraisal tool was used to assess the quality of reporting, external validity, risk of bias, risk of confounding and power of each study.

RESULTS

Of the 3084 abstracts screened, 350 studies met the inclusion criteria. Oral and maxillofacial surgery contained 58.3% of studies, and 23.7% covered the musculoskeletal system. Only 21 studies were randomised controlled trials (RCTs), and all fitted within these two fields. The majority of RCTs were 3D-printed anatomical models for preoperative planning and guides for aiding surgery. The main benefits of these devices were decreased surgical operation times and increased surgical accuracy.

CONCLUSIONS

All medical fields that assessed 3D-printed devices concluded that they were clinically effective. The fields that most rigorously assessed 3D-printed devices were oral and maxillofacial surgery and the musculoskeletal system, both of which concluded that the 3D-printed devices outperformed their conventional comparators. However, the efficacy and effectiveness of 3D-printed devices remain undetermined for the majority of medical fields. 3D-printed devices can play an important role in healthcare, but more rigorous and long-term assessments are needed to determine if 3D-printed devices are clinically relevant before they become part of standard clinical practice.

3D-Printed Models of Cleft Lip and Palate for Surgical Training and Patient Education

Background:

Sculpted physical models and castings of the anatomy of cleft lip and palate are used for parent, patient, and trainee education of cleft lip and palate conditions. In this study, we designed a suite of digital 3-dimensional (3D) models of cleft lip and palate anatomy with additive manufacturing techniques for patient education.

Methods:

CT scans of subjects with isolated cleft palate, unilateral and bilateral cleft lip and palate, and a control were obtained. Soft tissue and bony structures were segmented and reconstructed into digital 3D models. The oral soft tissues overlying the cleft palate were manually molded with silicone putty and scanned using CT to create digital 3D models. These were then combined with the original model to integrate with segmentable soft tissues. Bone and soft tissues were 3D printed in different materials to mimic the rigidity/softness of the relevant anatomy. These models were presented to the parents/patients at our craniofacial clinic. Visual analog scale (VAS) surveys were obtained pertaining to the particular use of the models, to ascertain their value in parental education.

Results:

A total of 30 parents of children with cleft conditions completed VAS evaluations. The models provided the parents with a better understanding of their child’s condition with an overall evaluation score of 9.35 ± 0.5.

Conclusions:

We introduce a suite of 3D-printed models of cleft conditions that has a useful role in patient, parental, and allied health education with highly positive feedback.

Custom-Made Titanium 3-Dimensional Printed Interbody Cages for Treatment of Osteoporotic Fracture-Related Spinal Deformity

BACKGROUND

Advances in minimally invasive interbody fusion have greatly enhanced surgeons' capability to correct adult spinal deformity with reduced morbidity. However, the feasibility of such approaches is limited in patients with previous osteoporotic fractures as the resultant vertebral deformity renders the end plate geometry incongruous with conventional interbody implants. Current 3-dimensional (3D) printing technology offers a novel solution by fabricating custom-made implants tailored to individual anatomy. We present the results of a patient with osteoporotic lumbar fractures treated by such technology.

CASE DESCRIPTION

A 74-year-old woman, with previous osteoporotic fractures at L2 and L3 resulting in concave deformity of the end plates, presented with intractable radiculopathy secondary to lateral recess and foraminal stenosis (L2-3 and L3-4). A minimally invasive lateral lumbar interbody fusion at L2-3 and L3-4 was considered favorable, but due to the associated vertebral collapse, off-the-shelf implants were not compatible with patient anatomy. In silico simulation based on preoperative computed tomography (CT) imaging was thus conducted to design customized cages to cater for the depressed recipient end plates and vertebral loss. The design was converted to implantable titanium cages through 3D additive manufacturing. At surgery, a tight fit between the implants and the targeted disk space was achieved. Postoperative CT scan confirmed excellent implant-end plate matching and restoration of lost disk space. The patient began to ambulate from postoperative day 1 and at 6-month follow-up resolution of radicular symptoms and CT evidence of interbody fusion were recorded.

CONCLUSIONS

3D-printed custom-made interbody cages can help overcome the difficulties in deformity correction secondary to osteoporotic fractures.

A paradigm shift in surgical planning and simulation using 3Dgraphy: Experience of first 50 surgeries done using 3D-printed biomodels

INTRODUCTION

Preoperative planning is an important aspect of any orthopedic surgery. Traditionally, surgeons mentally rehearse the operation and anticipate problems based on data available from "radiography" like MRI and CT. 3D printed bio-models and tools, or "3Dgraphy" can simplify this mental exercise and provide a realistic and user-friendly portrayal of this radiographic data.

METHODS

Five surgeons participated in this multicenter study. 3D printed biomodels were obtained for 50 surgical cases that included periarticular trauma (24), pelvic trauma (11), complex primary (7), and revision arthroplasty (8). CT scan data was used to generate computer models which were then 3D printed in real size. These models were used to understand pathoanatomy and conduct simulated surgery as a part of preoperative planning. The models were sterilized and were used for intraoperative referencing. Following each case, the operating surgeon was asked to fill out a structured questionnaire to report on the perceived benefits of these tools.

RESULTS

All surgeons reported that the biomodels provided additional information to conventional imaging that enhanced their knowledge of the complex pathoanatomy. It was useful in preoperative planning, rehearsing the operation, surgical simulation, intraoperative referencing, surgical navigation, preoperative implant selection, and inventory management. This probably reduced surgical time and improved accuracy of the surgery. All surgeons reported that they would not only use it themselves but also recommend it to other surgeons.

CONCLUSION

3Dgraphy was found to be a valuable tool in orthopedic surgeries that involve complex pathoanatomy like pelvic trauma, revision arthroplasty, and periarticular fracture. As the technology evolves and improves, they are likely to become a standard component of many orthopedic procedures.

Prebending of osteosynthesis plate using 3D printed models to treat symptomatic os acromiale and acromial fracture

BACKGROUND

A symptomatic os acromiale can lead to impingement syndrome and rotator cuff tendinopathy. An acromion fracture is often part of a more complex scapular trauma that needs stabilisation.

METHODS

We developed a new technique using a three-dimensional (3D) model and a distal clavicle reconstruction plate to treat os acromiale and acromion fractures. Our hypothesis was that such an approach would be a useful addition to the existing techniques. First, a 3D model of the acromion was printed, then an osteosynthesis plate was pre-bent to fit the exact shape and curve of the acromion. We tested this technique and present reports on five patients, three with os acromiales and two with acromial fractures. We followed these patients during their rehabilitation and evaluated them using the Constant-Murley and the Disabilities of the Arm, Shoulder and Hand scores.

RESULTS

In every case the fracture or non-union healed. If the surgery was performed before additional damage (such as an impingement syndrome) occurred, we saw that the patient's pain completely disappeared. This new technique also has other advantages because the surgeon can prepare the entire operation in advance, which reduces the duration of surgery. Another advantage of using a 3D model is that it can also be used to inform the patient and the surgical team about the planned operation.

CONCLUSION

This new technique using a preoperative patient-customized plate is a good alternative for use in open reduction and internal fixation, particularly if the patient has no other conditions.

Reconstruction of Liposarcoma Resection Defect With a Made-to-Measure Polyethylene Prosthesis Using Three-Dimensional Digital Technology

BACKGROUND

Liposarcoma is considered one of the most frequently occurring tumors of the soft tissues, representing 17% to 30% of all mesenchymal cell tumors. It is less common in the head and neck representing <10% of tumors in this region. The reconstruction of defects derived from resection of these tumors presents a surgical challenge. New three-dimensional digital technologies allow more exact surgery, cause less morbidity, and achieve adequate aesthetic outcomes.

OBJECTIVE

The aim of this article was to describe the complex reconstruction of a defect caused by the resection of a liposarcoma in the temporal region.

METHODS

Three-dimensional technology allowed patient planning and a reconstruction that was as exact as possible. A made-to-measure polymethyl methacrylate prosthesis was used to correct the defect in the zygomatic arch. The temporal fossa was covered with a standard porous polyethylene prosthesis.

CONCLUSIONS

Satisfactory esthetic and functional results were achieved using three-dimensional digital technology for treatment planning and to fabricate a made-to-measure polyethylene prosthesis and surgical guide.

Three-dimensional printing in contemporary fixed prosthodontics: A technique article

Digital dentistry has gained in popularity among clinicians and laboratory technicians because of its versatile applications. Three-dimensional (3D) printing has been applied in many areas of dentistry as it offers efficiency, affordability, accessibility, reproducibility, speed, and accuracy. This article describes a technique where 3D printing is used to fabricate a die-trimmed cast and to replicate gingival tissue and implant analogs. The digital workflow that replaces the conventional laboratory procedure is outlined.

Systematic review of 3D printing in spinal surgery: the current state of play

Three-dimensional printing (3DP), also known as "Additive Manufacturing", is a rapidly growing industry, particularly in the area of spinal surgery. Given the complex anatomy of the spine and delicate nature of surrounding structures, 3DP has the potential to aid surgical planning and procedural accuracy. We perform a systematic review of current literature on the applications of 3DP in spinal surgery. Six electronic databases were searched for original published studies reporting cases or outcomes for 3DP surgical models, guides or implants for spinal surgery. The findings of these studies were synthesized and summarized. These searches returned a combined 2,411 articles. Of these, 54 were included in this review. 3DP is currently used for surgical planning, intra-operative surgical guides, customised prostheses as well as "Off-the-Shelf" implants. The technology has the potential for enhanced implant properties, as well as decreased surgical time and better patient outcomes. The majority of the data thus far is from low-quality studies with inherent biases linked with the excitement of a new field. As the body of literature continues to expand, larger scale studies to evaluate advantages and disadvantages, and longer-term follow up will enhance our knowledge of the effect 3DP has in spinal surgery. In addition, issues such as financial impact, time to design and print, materials selection and bio-printing will evolve as this rapidly expanding field matures.

Measuring and Establishing the Accuracy and Reproducibility of 3D Printed Medical Models

Despite the rapid growth of three-dimensional (3D) printing applications in medicine, the accuracy and reproducibility of 3D printed medical models have not been thoroughly investigated. Although current technologies enable 3D models to be created with accuracy within the limits of clinical imaging spatial resolutions, this is not always achieved in practice. Inaccuracies are due to errors that occur during the imaging, segmentation, postprocessing, and 3D printing steps. Radiologists' understanding of the factors that influence 3D printed model accuracy and the metrics used to measure this accuracy is key in directing appropriate practices and establishing reference standards and validation procedures. The authors review the various factors in each step of the 3D model printing process that contribute to model inaccuracy, including the intrinsic limitations of each printing technology. In addition, common sources of model inaccuracy are illustrated. Metrics involving comparisons of model dimensions and morphology that have been developed to quantify differences between 3D models also are described and illustrated. These metrics can be used to define the accuracy of a model, as compared with the reference standard, and to measure the variability of models created by different observers or using different workflows. The accuracies reported for specific indications of 3D printing are summarized, and potential guidelines for quality assurance and workflow assessment are discussed. Online supplemental material is available for this article. ©RSNA, 2017.

Fabrication of arbitrary 3D components in cardiac surgery: from macro-, micro- to nanoscale

Fabrication of tissue-/organ-like structures at arbitrary geometries by mimicking the properties of the complex material offers enormous interest to the research and clinical applicability in cardiovascular diseases. Patient-specific, durable, and realistic three-dimensional (3D) cardiac models for anatomic consideration have been developed for education, pro-surgery planning, and intra-surgery guidance. In cardiac tissue engineering (TE), 3D printing technology is the most convenient and efficient microfabrication method to create biomimetic cardiovascular tissue for the potential in vivo implantation. Although booming rapidly, this technology is still in its infancy. Herein, we provide an emphasis on the application of this technology in clinical practices, micro- and nanoscale fabrications by cardiac TE. Initially, we will give an overview on the fabrication methods that can be used to synthesize the arbitrary 3D components with controlled features and will subsequently highlight the current limitations and future perspective of 3D printing used for cardiovascular diseases.

Advanced Pediatric Airway Simulation

Simulation is an emerging and viable means to increase pediatric airway surgical training. A variety of simulators currently exist that may be used or modified for laryngoscopy, bronchoscopy, and endoscopic intervention, although anatomic realism and utility for complex procedures are limited. There is a need for further development of improved endoscopic and anatomic models. Innovative techniques are enabling small-scale manufacturing of generalizable and patient-specific simulators. The high acuity of the pediatric airway patient makes the use of simulation an attractive modality for training, competency maintenance, and patient safety quality-improvement studies.

Proposal of custom made wrist orthoses based on 3D modelling and 3D printing

Accessibility to three-dimensional (3D) technologies, such as 3D scanning systems and additive manufacturing (like 3D printers), allows a variety of 3D applications. For medical applications in particular, these modalities are gaining a lot of attention enabling several opportunities for healthcare applications. The literature brings several cases applying both technologies, but none of them focus on the spreading of how this technology could benefit the health segment. This paper proposes a new methodology, which employs both 3D modelling and 3D printing for building orthoses, which could better fit the demands of different patients. Additionally, there is an opportunity for sharing expertise, as it represents a trendy in terms of the maker-movement. Therefore, as a result of the proposed approach, we present a case study based on a volunteer who needs an immobilization orthosis, which was built for exemplification of the whole process. This proposal also employs freely available 3D models and software, having a strong social impact. As a result, it enables the implementation and effective usability for a variety of built to fit solutions, hitching useful and smarter technologies for the healthcare sector.

Accuracy assessment of surgical planning and three-dimensional-printed patient-specific guides for orthopaedic osteotomies

This study analyses the accuracy of three-dimensional pre-operative planning and patient-specific guides for orthopaedic osteotomies. To this end, patient-specific guides were compared to the classical freehand method in an experimental setup with saw bones in two phases. In the first phase, the effect of guide design and oscillating versus reciprocating saws was analysed. The difference between target and performed cuts was quantified by the average distance deviation and average angular deviations in the sagittal and coronal planes for the different osteotomies. The results indicated that for one model osteotomy, the use of guides resulted in a more accurate cut when compared to the freehand technique. Reciprocating saws and slot guides improved accuracy in all planes, while oscillating saws and open guides lead to larger deviations from the planned cut. In the second phase, the accuracy of transfer of the planning to the surgical field with slot guides and a reciprocating saw was assessed and compared to the classical planning and freehand cutting method. The pre-operative plan was transferred with high accuracy. Three-dimensional-printed patient-specific guides improve the accuracy of osteotomies and bony resections in an experimental setup compared to conventional freehand methods. The improved accuracy is related to (1) a detailed and qualitative pre-operative plan and (2) an accurate transfer of the planning to the operation room with patient-specific guides by an accurate guidance of the surgical tools to perform the desired cuts.

Three-Dimensional Printed Fish Graders: A Tool to Rapidly and Reliably Size Select Zebrafish

Research into adult zebrafish often requires fish to be of a specific size. Currently, fish must be individually measured to achieve this goal. Here, we design and utilize fish graders to quickly sort fish by width. We characterize graders individually for the length of fish they discriminate between and we also analyze graders in pairs to define the range of lengths for a retained population of fish. We note that a 1 mm increase of fish width increases fish length by 6.2-7.2 mm. We provide the schematics to print a series of eight retention widths, and note that graders of any desired retention width can easily be printed by slightly modifying our design files.

3D Printing in Liver Surgery: A Systematic Review

BACKGROUND

Rapid growth of three-dimensional (3D) printing in recent years has led to new applications of this technology across all medical fields. This review article presents a broad range of examples on how 3D printing is facilitating liver surgery, including models for preoperative planning, education, and simulation.

MATERIALS AND METHODS

We have performed an extensive search of the medical databases Ovid/MEDLINE and PubMed/EMBASE and screened articles fitting the scope of review, following previously established exclusion criteria. Articles deemed suitable were analyzed and data on the 3D-printed models-including both technical properties and desirable application-and their impact on clinical proceedings were extracted.

RESULTS

Fourteen articles, presenting unique utilizations of 3D models, were found suitable for data analysis. A great majority of articles (93%) discussed models used for preoperative planning and intraoperative guidance. PolyJet was the most common (43%) and, at the same time, most expensive 3D printing technology used in the development process. Many authors of reviewed articles reported that models were accurate (71%) and allowed them to understand patient's complex anatomy and its spatial relationships.

CONCLUSIONS

Although the technology is still in its early stages, presented models are considered useful in preoperative planning and patient and student education. There are multiple factors limiting the use of 3D printing in everyday healthcare, the most important being high costs and the time-consuming process of development. Promising early results need to be verified in larger randomized trials, which will provide more statistically significant results.

The utility of 3D printing for surgical planning and patient-specific implant design for complex spinal pathologies: case report

OBJECTIVE

There has been a recent renewed interest in the use and potential applications of 3D printing in the assistance of surgical planning and the development of personalized prostheses. There have been few reports on the use of 3D printing for implants designed to be used in complex spinal surgery.

METHODS

The authors report 2 cases in which 3D printing was used for surgical planning as a preoperative mold, and for a custom-designed titanium prosthesis: one patient with a C-1/C-2 chordoma who underwent tumor resection and vertebral reconstruction, and another patient with a custom-designed titanium anterior fusion cage for an unusual congenital spinal deformity.

RESULTS

In both presented cases, the custom-designed and custom-built implants were easily slotted into position, which facilitated the surgery and shortened the procedure time, avoiding further complex reconstruction such as harvesting rib or fibular grafts and fashioning these grafts intraoperatively to fit the defect. Radiological follow-up for both cases demonstrated successful fusion at 9 and 12 months, respectively.

CONCLUSIONS

These cases demonstrate the feasibility of the use of 3D modeling and printing to develop personalized prostheses and can ease the difficulty of complex spinal surgery. Possible future directions of research include the combination of 3D-printed implants and biologics, as well as the development of bioceramic composites and custom implants for load-bearing purposes.

Three-Dimensional Printing of Medicinal Products and the Challenge of Personalized Therapy

By 3-dimensional (3D) printing, solid objects of any shape are fabricated through layer-by-layer addition of materials based on a digital model. At present, such a technique is broadly exploited in many industrial fields because of major advantages in terms of reduced times and costs of development and production. In the biomedical and pharmaceutical domains, the interest in 3D printing is growing in step with the needs of personalized medicine. Printed scaffolds and prostheses have partly replaced medical devices produced by more established techniques, and more recently, 3D printing has been proposed for the manufacturing of drug products. Notably, the availability of patient-tailored pharmaceuticals would be of utmost importance for children, elderly subjects, poor and high metabolizers, and individuals undergoing multiple drug treatments. 3D printing encompasses a range of differing techniques, each involving advantages and open issues. Particularly, solidification of powder, extrusion, and stereolithography have been applied to the manufacturing of drug products. The main challenge to their exploitation for personalized pharmacologic therapy is likely to be related to the regulatory issues involved and to implementation of production models that may allow to efficiently turn the therapeutic needs of individual patients into small batches of appropriate drug products meeting preset quality requirements.

Three-dimensional Printed Cardiac Models: Applications in the Field of Medical Education, Cardiovascular Surgery, and Structural Heart Interventions

In recent years, three-dimensional (3D) printed models have been incorporated into cardiology because of their potential usefulness in enhancing understanding of congenital heart disease, surgical planning, and simulation of structural percutaneous interventions. This review provides an introduction to 3D printing technology and identifies the elements needed to construct a 3D model: the types of imaging modalities that can be used, their minimum quality requirements, and the kinds of 3D printers available. The review also assesses the usefulness of 3D printed models in medical education, specialist physician training, and patient communication. We also review the most recent applications of 3D models in surgical planning and simulation of percutaneous structural heart interventions. Finally, the current limitations of 3D printing and its future directions are discussed to explore potential new applications in this exciting medical field.

Cost-effective, personalized, 3D-printed liver model for preoperative planning before laparoscopic liver hemihepatectomy for colorectal cancer metastases

Purpose

Three-dimensional (3D) printing for preoperative planning has been intensively developed in the recent years. However, the implementation of these solutions in hospitals is still difficult due to high costs, extremely expensive industrial-grade printers, and software that is difficult to obtain and learn along with a lack of a defined process. This paper presents a cost-effective technique of preparing 3D-printed liver models that preserves the shape and all of the structures, including the vessels and the tumor, which in the present case is colorectal liver metastasis.

Methods

The patient’s computed tomography scans were used for the separation and visualization of virtual 3D anatomical structures. Those elements were transformed into stereolithographic files and subsequently printed on a desktop 3D printer. The multipart structure was assembled and filled with silicone. The patient underwent subsequent laparoscopic right hemihepatectomy. The entire process is described step-by-step, and only free-to-use and mostly open-source software was used.

Results

As a result, a transparent, full-sized liver model with visible vessels and colorectal metastasis was created for under $150, which—taking into account 3D printer prices—is much cheaper than models presented in previous research papers.

Conclusions

The increased accessibility of 3D models for physicians before complex laparoscopic surgical procedures such as hepatic resections could lead to beneficial breakthroughs in these sophisticated surgeries, as many reports show that these models reduce operative time and improve short term outcomes.

Customized a Ti6Al4V Bone Plate for Complex Pelvic Fracture by Selective Laser Melting

In pelvic fracture operations, bone plate shaping is challenging and the operation time is long. To address this issue, a customized bone plate was designed and produced using selective laser melting (SLM) technology. The key steps of this study included designing the customized bone plate, metal 3D printing, vacuum heat treatment, surface post-processing, operation rehearsal, and clinical application and evaluation. The joint surface of the bone plate was placed upwards with respect to the build platform to keep it away from the support and to improve the quality of the joint surface. Heat conduction was enhanced by adding a cone-type support beneath the bone plate to prevent low-quality fabrication due to poor heat conductivity of the Ti-6Al-4V powder. The residual stress was eliminated by exposing the SLM-fabricated titanium-alloy bone plate to a vacuum heat treatment. Results indicated that the bone plate has a hardness of HV1 360–HV1 390, an ultimate tensile strength of 1000–1100 MPa, yield strength of 900–950 MPa, and an elongation of 8%–10%. Pre-operative experiments and operation rehearsal were performed using the customized bone plate and the ABC-made pelvic model. Finally, the customized bone plate was clinically applied. The intraoperative C-arm and postoperative X-ray imaging results indicated that the customized bone plate matched well to the damaged pelvis. The customized bone plate fixed the broken bone and guides pelvis restoration while reducing operation time to about two hours. The customized bone plate eliminated the need for preoperative titanium plate pre-bending, thereby greatly reducing surgical wounds and operation time.

Three-dimensional-printed cardiac prototypes aid surgical decision-making and preoperative planning in selected cases of complex congenital heart diseases: Early experience and proof of concept in a resource-limited environment

Introduction:

Three-dimensional. (3D) printing is an innovative manufacturing process that allows computer-assisted conversion of 3D imaging data into physical “printouts” Healthcare applications are currently in evolution.

Objective:

The objective of this study was to explore the feasibility and impact of using patient-specific 3D-printed cardiac prototypes derived from high-resolution medical imaging data (cardiac magnetic resonance imaging/computed tomography [MRI/CT]) on surgical decision-making and preoperative planning in selected cases of complex congenital heart diseases (CHDs).

Materials and Methods:

Five patients with complex CHD with previously unresolved management decisions were chosen. These included two patients with complex double-outlet right ventricle, two patients with criss-cross atrioventricular connections, and one patient with congenitally corrected transposition of great arteries with pulmonary atresia. Cardiac MRI was done for all patients, cardiac CT for one; specific surgical challenges were identified. Volumetric data were used to generate patient-specific 3D models. All cases were reviewed along with their 3D models, and the impact on surgical decision-making and preoperative planning was assessed.

Results:

Accurate life-sized 3D cardiac prototypes were successfully created for all patients. The models enabled radically improved 3D understanding of anatomy, identification of specific technical challenges, and precise surgical planning. Augmentation of existing clinical and imaging data by 3D prototypes allowed successful execution of complex surgeries for all five patients, in accordance with the preoperative planning.

Conclusions:

3D-printed cardiac prototypes can radically assist decision-making, planning, and safe execution of complex congenital heart surgery by improving understanding of 3D anatomy and allowing anticipation of technical challenges.

Applications of Three-Dimensional Printing in Surgery

Three-dimensional (3D) printing is a rapidly advancing technology in the field of surgery. This article reviews its contemporary applications in 3 aspects of surgery, namely, surgical planning, implants and prostheses, and education and training. Three-dimensional printing technology can contribute to surgical planning by depicting precise personalized anatomy and thus a potential improvement in surgical outcome. For implants and prosthesis, the technology might overcome the limitations of conventional methods such as visual discrepancy from the recipient's body and unmatching anatomy. In addition, 3D printing technology could be integrated into medical school curriculum, supplementing the conventional cadaver-based education and training in anatomy and surgery. Future potential applications of 3D printing in surgery, mainly in the areas of skin, nerve, and vascular graft preparation as well as ear reconstruction, are also discussed. Numerous trials and studies are still ongoing. However, scientists and clinicians are still encountering some limitations of the technology including high cost, long processing time, unsatisfactory mechanical properties, and suboptimal accuracy. These limitations might potentially hamper the applications of this technology in daily clinical practice.

Additive Manufacturing for Surgical Planning of Mandibular Fracture

Currently, imaging techniques such as Computed Tomography with three-dimensional reconstruction (3D) and Magnetic Resonances are being routinely used in pre-surgical planning in all fields of medicine. Nowadays, virtual three-dimensional images, commonly displayed on two-dimensional surfaces, such as the computer screen, can be used to produce rapidly prototyped models, with excellent dimensional accuracy and fine reproduction of anatomical structures, providing professionals with the ability to use the biomodel in planning and simulating medical and dental procedures (oral and maxillofacial surgery, making individualized facial implants and prostheses, measurements and previous adaptations of prefabricated fixation plates), thus contributing to considerable reductions in surgical time and consequently the duration of anesthesia, minimizing infection risks and reducing hospital costs. In this report, we describe a case of surgical planning and treatment of bilateral atrophic mandibular fracture, in which, for surgical planning, authors used Rapid Prototyping as an adjunct tool, considering the advantages already outlined.

Surgical applications of three-dimensional printing: a review of the current literature & how to get started

Three dimensional (3D) printing involves a number of additive manufacturing techniques that are used to build structures from the ground up. This technology has been adapted to a wide range of surgical applications at an impressive rate. It has been used to print patient-specific anatomic models, implants, prosthetics, external fixators, splints, surgical instrumentation, and surgical cutting guides. The profound utility of this technology in surgery explains the exponential growth. It is important to learn how 3D printing has been used in surgery and how to potentially apply this technology. PubMed was searched for studies that addressed the clinical application of 3D printing in all surgical fields, yielding 442 results. Data was manually extracted from the 168 included studies. We found an exponential increase in studies addressing surgical applications for 3D printing since 2011, with the largest growth in craniofacial, oromaxillofacial, and cardiothoracic specialties. The pertinent considerations for getting started with 3D printing were identified and are discussed, including, software, printing techniques, printing materials, sterilization of printing materials, and cost and time requirements. Also, the diverse and increasing applications of 3D printing were recorded and are discussed. There is large array of potential applications for 3D printing. Decreasing cost and increasing ease of use are making this technology more available. Incorporating 3D printing into a surgical practice can be a rewarding process that yields impressive results.

Application of a 3D custom printed patient specific spinal implant for C1/2 arthrodesis

The study aims to describe a three-dimensional printed (3DP) posterior fixation implant used for C1/C2 fusion in a 65-year-old female. Spinal fusion remains a common intervention for a range of spinal pathologies including degenerative disc and facet disease when conservative methods are unsuccessful. However, fusion devices are not always entirely efficacious in providing the desired fixation, and surgeons rely on 'off the shelf' implants which may not provide an anatomical fit to address the particular pathology. 3DP refers to a process where three-dimensional objects are created through successive layering of material, so called 'additive manufacturing'. Although this technology enables accurate fabrication of patient-specific orthopaedic and spinal implants, literature on its utilization in this regard is rare. A 65-year-old female, with severe facet arthropathy at the C1/C2 level, osteophyte formation and impingement of the exiting C2 nerve root underwent a C1/C2 posterior fusion and rhizolysis of the C2 nerve roots. A custom posterior fixation implant was designed and on-laid over the C2 spinous process and lamina, with screw holes made to a depth and angulation that was pre-calculated based on the preoperative CT based 3D modelling. The patient had an uneventful recovery and reported a significant reduction in occipital neuralgia and sub-occipital pain and 2-month follow-up. We report the first case of a customized 3DP spinal prosthesis for posterior C1/C2 fusion. The implant added significant value reducing the overall time of the procedure, and safety with a reduced risk of neurovascular compromise.

Three-Dimensional Printing and Its Applications in Otorhinolaryngology-Head and Neck Surgery

Objective Three-dimensional (3D)-printing technology is being employed in a variety of medical and surgical specialties to improve patient care and advance resident physician training. As the costs of implementing 3D printing have declined, the use of this technology has expanded, especially within surgical specialties. This article explores the types of 3D printing available, highlights the benefits and drawbacks of each methodology, provides examples of how 3D printing has been applied within the field of otolaryngology-head and neck surgery, discusses future innovations, and explores the financial impact of these advances. Data Sources Articles were identified from PubMed and Ovid MEDLINE. Review Methods PubMed and Ovid Medline were queried for English articles published between 2011 and 2016, including a few articles prior to this time as relevant examples. Search terms included 3-dimensional printing, 3 D printing, otolaryngology, additive manufacturing, craniofacial, reconstruction, temporal bone, airway, sinus, cost, and anatomic models. Conclusions Three-dimensional printing has been used in recent years in otolaryngology for preoperative planning, education, prostheses, grafting, and reconstruction. Emerging technologies include the printing of tissue scaffolds for the auricle and nose, more realistic training models, and personalized implantable medical devices. Implications for Practice After the up-front costs of 3D printing are accounted for, its utilization in surgical models, patient-specific implants, and custom instruments can reduce operating room time and thus decrease costs. Educational and training models provide an opportunity to better visualize anomalies, practice surgical technique, predict problems that might arise, and improve quality by reducing mistakes.

3D-printed patient-specific applications in orthopedics

With advances in both medical imaging and computer programming, two-dimensional axial images can be processed into other reformatted views (sagittal and coronal) and three-dimensional (3D) virtual models that represent a patients’ own anatomy. This processed digital information can be analyzed in detail by orthopedic surgeons to perform patient-specific orthopedic procedures. The use of 3D printing is rising and has become more prevalent in medical applications over the last decade as surgeons and researchers are increasingly utilizing the technology’s flexibility in manufacturing objects. 3D printing is a type of manufacturing process in which materials such as plastic or metal are deposited in layers to create a 3D object from a digital model. This additive manufacturing method has the advantage of fabricating objects with complex freeform geometry, which is impossible using traditional subtractive manufacturing methods. Specifically in surgical applications, the 3D printing techniques can not only generate models that give a better understanding of the complex anatomy and pathology of the patients and aid in education and surgical training, but can also produce patient-specific surgical guides or even custom implants that are tailor-made to the surgical requirements. As the clinical workflow of the 3D printing technology continues to evolve, orthopedic surgeons should embrace the latest knowledge of the technology and incorporate it into their clinical practice for patient-specific orthopedic applications. This paper is written to help orthopedic surgeons stay up-to-date on the emerging 3D technology, starting from the acquisition of clinical imaging to 3D printing for patient-specific applications in orthopedics. It 1) presents the necessary steps to prepare the medical images that are required for 3D printing, 2) reviews the current applications of 3D printing in patient-specific orthopedic procedures, 3) discusses the potential advantages and limitations of 3D-printed custom orthopedic implants, and 4) suggests the directions for future development. The 3D printing technology has been reported to be beneficial in patient-specific orthopedics, such as in the creation of anatomic models for surgical planning, education and surgical training, patient-specific instruments, and 3D-printed custom implants. Besides being anatomically conformed to a patient’s surgical requirement, 3D-printed implants can be fabricated with scaffold lattices that may facilitate osteointegration and reduce implant stiffness. However, limitations including high cost of the implants, the lead time in manufacturing, and lack of intraoperative flexibility need to be addressed. New biomimetic materials have been investigated for use in 3D printing. To increase utilization of 3D printing technology in orthopedics, an all-in-one computer platform should be developed for easy planning and seamless communications among different care providers. Further studies are needed to investigate the real clinical efficacy of 3D printings in orthopedic applications.

Applications of 3D printing in the management of severe spinal conditions

The latest and fastest-growing innovation in the medical field has been the advent of three-dimensional printing technologies, which have recently seen applications in the production of low-cost, patient-specific medical implants. While a wide range of three-dimensional printing systems has been explored in manufacturing anatomical models and devices for the medical setting, their applications are cutting-edge in the field of spinal surgery. This review aims to provide a comprehensive overview and classification of the current applications of three-dimensional printing technologies in spine care. Although three-dimensional printing technology has been widely used for the construction of patient-specific anatomical models of the spine and intraoperative guide templates to provide personalized surgical planning and increase pedicle screw placement accuracy, only few studies have been focused on the manufacturing of spinal implants. Therefore, three-dimensional printed custom-designed intervertebral fusion devices, artificial vertebral bodies and disc substitutes for total disc replacement, along with tissue engineering strategies focused on scaffold constructs for bone and cartilage regeneration, represent a set of promising applications towards the trend of individualized patient care.