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The purpose of this paper is to develop a process chain for design and manufacture of endplates of intervertebral disc implants, with specific emphasis on designing footprint profiles and matching endplate geometry.

Existing techniques for acquiring patient‐specific information from CT scan data was and a user‐friendly software solution was developed to facilitate pre‐surgical planning and semi‐automated design. The steps in the process chain were validated experimentally by manufacturing Ti6Al4 V endplates by means of Direct Metal Laser Sintering to match vertebrae of a cadaver and were tested for accuracy of the implant‐to‐bone fitment.

Intervertebral disc endplates were successfully designed and rapid manufactured using a biocompatible material. Accuracy within 0.37 mm was achieved. User‐friendly, semi‐automated design software offers an opportunity for surgeons to become more easily involved in the design process and speeds up the process to more accurately develop a custom‐made implant.

This research is limited to the design and manufacture of the bone‐implant contacting interface. Other design features, such as keels which are commonly used for implant fixation as well as the functionality of the implant joint mechanics were not considered as there may be several feasible design alternatives.

This research may change the way that current intervertebral disc implants are designed and manufactured.

Apart from other areas of application (cranial, maxillofacial, hip, knee, foot) and recent research on customized disc nucleus replacement, very little work has been done to develop patient‐specific implants for the spine. This research was conducted to contribute and provide much needed progress in this area of application.

The purpose of this paper is to identify the key design process factors acting as drivers or barriers to routine health service adoption of additively manufactured (AM) patient-specific devices. The technical efficacy of, and clinical benefits from, using computer-aided design (CAD) and AM in the production of such devices (implants and guides) has been established. Despite this, they are still not commonplace. With AM equipment and CAD tool costs largely outside of the clinician’s or designer’s control, the opportunity exists to explore design process improvement routes to facilitate routine health service implementation.

A literature review, new data from three separate clinical case studies and experience from an institute working on collaborative research and commercial application of CAD/AM in the maxillofacial specialty, were analysed to extract a list and formulate models of design process factors.

A semi-digital design and fabrication process is currently the lowest cost and shortest duration for cranioplasty implant production. The key design process factor to address is the fidelity of the device design specification.

Further research into the relative values of, and best methods to address the key factors is required; to work towards the development of new design tools. A wider range of benchmarked case studies is required to assess costs and timings beyond one implant type.

Design process factors are identified (building on previous work largely restricted to technical and clinical efficacy). Additionally, three implant design and fabrication workflows are directly compared for costs and time. Unusually, a design process failure is detailed. A new model is proposed – describing design process factor relationships and the desired impact of future design tools.

The purpose of this paper is to establish a methodology for the design and development of patient-specific elbow implant with an elastic modulus close to that of the human bone. One of the most preferred implant material is titanium alloy which is about 8 to 9 times higher in strength than that of the human bone and is the closest than other metallic biomedical materials.

The methodology begins with the design of the implant from patient-specific computed tomography information and incorporates the manufacturing of the implant via a novel rapid prototyping assisted microwave sintering process.

The elastic modulus and the flexural strength of the implant were observed to be comparable to that of human elbow bones. The fatigue test depicts that the implant survives the one million cycles under physiological loading conditions. Other mechanical properties such as impact energy absorption, hardness and life cycle tests were also evaluated. The implant surface promotes human cell growth and adhesion and does not cause any adverse or undesired effects i.e. no cytotoxicity.

Stress shielding, and therefore, aseptic loosening of the implant shall be avoided. In the event of any trauma post-implantation, the implant would not hurt the patient.

The present study describes a methodology for the first time to be able to obtain the strength required for the medical implant without sacrificing the fatigue life requirement.

The purpose of this paper is to design and development of a patient-specific implant for zygomatic area of a patient suffering from mucormycosis (fungal infection). The paper describes how integration of computer-aided design (CAD) and 3D printing can be successfully used for developing custom implants for the sites for which readymade optimal solutions are not available.

The CT scan data of the patient were used for the generation of a 3D model. The healthy side of skull was mirrored and copied on the infected part, which served as a base for designing the implant. The prototype of the implant was printed using fused deposition modelling before finally printing in Ti6Al4V alloy using direct metal laser sintering process.

The custom designed implant fitted well to the patient’s skull during surgery. Proper facial aesthetics were maintained post-surgery.

The work describes the application of CAD-based image processing software and additive manufacturing in the development of a custom implant for the sites for which no readymade optimal solution is available.

The purpose of this paper was to find a successful treatment modality for patients suffering from temporomandibular joint (TMJ) ankylosis who could not be treated through traditional surgeries.

This work integrated the unique capabilities of the imaging technique, the rapid prototyping (RP) technology and the advanced manufacturing technique to develop the customised TMJ implant. The patient specific TMJ implant was fabricated using the computed tomography scanned data and the fused deposition modeling of RP for the TMJ surgery.

This approach showed good results in fabrication of the TMJ implant. Postoperatively, the patient experienced normalcy in the jaw movements.

Advanced technologies helped to fabricate the customised TMJ implant. The advantage of this approach is that the physical RP model assisted in designing the final metallic implant. It also helped in the surgical planning and the rehearsals.

This case report illustrates the benefits of imaging/computer‐aided design/computer‐aided manufacturing/RP to develop the customised implant and serve those patients who could not be treated in the traditional way.

This study aims to identify 3D-printed medical model (3DPMM) supply chain barriers that affect the supply chain of 3DPMM in the Indian context and investigate the interdependencies between the barriers to establish hierarchical relations between them to improve the supply chain.

The methodology used interpretive structural modeling (ISM) and a decision-making trial and evaluation laboratory (DEMATEL) to identify the hierarchical and contextual relations among the barriers to the 3DPMM supply chain.

A total of 15 3DPMM supply chain barriers were identified in this study. The analysis identified limited materials options, slow production speed, manual post-processing, high-skilled data analyst, design and customization expert and simulation accuracy as the significant driving barriers for the medical models supply chain for hospitals. In addition, the authors identified linkage and dependent barriers. The present study findings would help to improve the 3DPMM supply chain.

There were no experts from other nations, so this study might have missed a few 3DPMM supply chain barriers that would have been significant from another nation’s perspective.

ISM would help practitioners minimize 3DPMM supply chain barriers, while DEMATEL allows practitioners to emphasize the causal effects of 3DPMM supply chain barriers.

This study minimizes the 3DPMM supply chain barriers for medical applications through a hybrid ISM and DEMATEL methodology that has not been investigated in the literature.

With technology advances, metallic implants claim to improve the quality and durability of human life. In the recent decade, Ti-6Al-4V biomaterial has been additively manufactured via selective laser melting (SLM) for orthopedic applications. This paper aims to provide state-of-the-art on mechanobiology of these fabricated components.

A literature review has been done to explore the potential of SLM fabricated Ti-6Al-4V porous lattice structures (LS) as bone substitutes. The emphasize was on the effect of process parameters and porosity on mechanical and biological properties. The papers published since 2007 were considered here. The keywords used to search were porous Ti-6Al-4V, additive manufacturing, metal three-dimensional printing, osseointegration, porous LS, SLM, in vitro and in vivo.

The properties of SLM porous biomaterials were compared with different human bones, and bulk SLM fabricated Ti-6Al-4V structures. The comparison was also made between LS with different unit cells to find out whether there is any particular design that can mimic the human bone functionality and enhance osseointegration.

The implant porosity plays a crucial role in mechanical and biological characteristics that relies on the optimum controlled process variables and design attributes. It was also indicated that although the mechanical strength (compressive and fatigue) of porous LS is not mostly close to natural cortical bone, elastic modulus can be adjusted to match that of cortical or cancellous bone. Porous Ti-6Al-4V provide favorable bone formation. However, the effect of design variables on biological behavior cannot be fully conclusive as few studies have been dedicated to this.

The aim of this study is to describe an improved experimental substrate for the mechanical testing of patient-specific implants fabricated using direct metal additive manufacturing processes. This method reduces variability and sample size requirements and addresses the importance of geometry at the bone/implant interface.

Short-fiber glass/resin materials for cortical bone and polyurethane foam materials for cancellous bone were evaluated using standard tensile coupons. A method for fabricating bone analogs with patient-specific geometries using rapid tooling is presented. Bone analogs of a canine radius were fabricated and compared to cadaveric specimens in several biomechanical tests as validation.

The analog materials exhibit a tensile modulus that falls within the range of expected values for cortical and cancellous bone. The tensile properties of the cortical bone analog vary with fiber loading. The canine radius models exhibited similar mechanical properties to the cadaveric specimens with a reduced variability.

Additional replications involving different bone geometries, types of bone and/or implants are required for a full validation. Further, the materials used here are only intended to mimic the mechanical properties of bone on a macro scale within a relatively narrow range. These analog models have not been shown to address the complex microscopic or viscoelastic behavior of bone in the present study.

Scientific data on the formulation and fabrication of bone analogs are absent from the literature. The literature also lacks an experimental platform that matches patient-specific implant/bone geometries at the bone implant interface.

The purpose of this paper is to develop a workflow for 3D modeling and additive manufacturing (AM) of patient‐specific medical implants. The comprehensive workflow consists of four steps: medical imaging; 3D modelling; additive manufacturing; and clinical application. Implants are used to reconstruct bone damage or defects caused by trauma or disease. Traditionally, implants have been manually bent and shaped, either preoperatively or intraoperatively, with the help of anatomic solid models. The proposed workflow obviates the manual procedure and may result in more accurate and cost‐effective implants.

A patient‐specific implant was digitally designed to reconstruct a facial bone defect. Several test pieces were additive manufactured from stainless steel and titanium by direct metal laser sintering (DMLS) technology. An additive manufactured titanium EOS Titanium Ti64 ELI reconstruction plate was successfully implanted onto the patient's injured orbital wall.

This method enables exact fitting of implants to surrounding tissues. Creating implants before surgery improves accuracy, may reduce operation time and decrease patient morbidity, hence improving quality of surgery. By using AM methods it is possible to manufacture a volumetric net structure, which also allows cells and tissues to grow through it to and from surrounding tissues. The net is created from surface and its thickness and hole size are adjustable. The implant can be designed so that its mass is low and therefore sensitivity to hot and cold temperatures is reduced.

The paper describes a novel technique to create patient‐specific reconstruction implants for facial bony defects.

Extrinsic trauma to the orbit may cause a blowout or orbital fracture, which often requires surgery for reconstruction of the orbit and repositioning of the eyeball with an implant. Post-operative complications, however, are high with the most frequent cause of complications being a mismatch of the position and shape of the implant and fracture. These mismatches may be reduced by computed tomography (CT) based modeling and three-dimensional (3D) printed guide. Therefore, the aim of this study is to propose and evaluate a patient-specific guide to shape an orbital implant using 3D printing.

Using CT images of a patient, an orbital fracture can be modeled to design an implant guide for positioning and shaping of the surface and boundaries of the implant. The guide was manufactured using UV curable plastic at 0.032 mm resolution by a 3D printer. The accuracy of this method was evaluated by micro-CT scanning of the surgical guides and shaping implants.

The length and depth of the 3D model, press-compressed and decompressed implants were compared. The mean differences in length were 0.67 ± 0.38 mm, 0.63 ± 0.28 mm and 0.10 ± 0.10 mm, and the mean differences in depth were 0.64 ± 0.37 mm, 1.22 ± 0.56 mm and 0.57 ± 0.23 mm, respectively. Statistical evaluation was performed with a Bland-Altman plot.

This study suggests a patient-specific guide to shape an orbital implant using 3D printing and evaluate the guiding accuracy of the implant versus the planned model.