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Design methods for medical rapid prototyping (RP) of personalized cranioplasty implants are presented in this paper. These methods are applicable to model cranioplasty implants for all types of the skull defects including beyond‐midline and multiple defects. The methods are based on two types of anatomical data, solid bone models (STereoLithography files – STL) and bone slice contours (Initial Graphics Exchange Specification – IGES and StrataSys Layer files – SSL). The bone solids and contours are constructed based on computed tomography scanning data, and these data are generated in medical image processing and STL slicing packages.

To relieve intracranial pressure and save patient inflicted with severe head injury, neurosurgeons restore cranial defects. These defects can be caused because of trauma or diseases (Osteomyelitis of bone) which are treated by cranioplasty, using the preserved bone of patient. In case of non-availability of bone, a cranial implant is generated using a biocompatible synthetic material, but this process is less accurate and time-consuming. Hence, this paper aims to present the use of rapid prototyping technology that allows the development of a more accurate patient-specific template and saves the surgery time.

A five-year-old girl patient having cranial defect was taken up for cranioplasty. CT (computed tomography) scans of the patient were used to generate 3D design of the implant suitable to conceal the defect on the left frontal portion using CAD/CAM (computer-aided design/ computer-aided manufacturing) software. The design was used for 3D printing to manufacture a base template, which was finally used to fabricate the actual implant using Simplex® P bone cement material to conceal the defect.

Surgery using Simplex® P implant was performed successfully on the patient, giving precise natural curvature to left frontal portion of the patient, decreasing surgery time by about 30 per cent.

The case demonstrates the development of a convenient, time-saving and aesthetically superior digital procedure to treat cranial defect in the absence of preserved bone flap using CT scan as input. 3D modelling and printing were deployed to produce an accurate template which was used to generate an implant using bone cement biocompatible material.

The purpose of this study is to evaluate the intra- and post-operative performance and safety of direct three dimensional printing (3DP) porous polyethylene implants in cranial reconstruction.

Prefabricated porous polyethylene implants were prepared by direct 3DP, and cranioplasty implantation was performed. Postoperative aesthetics, patient satisfaction, firmness of the implant, reactions to the implant and 3D computed tomography (CT) scanning were assessed after 2, 6, 12 and 24 months postoperatively.

No complications after surgery were encountered. Excellent aesthetic results were obtained in all cases, and all the patients were satisfied with the reconstruction outcome. Bone density structure was found to ingrowth into these direct 3DP porous polyethylene implants and the content increased with increasing follow-up times.

This study was a pilot study conducted in a single group and evaluated in a short-term period. The bone formation and ingrowth were indirectly assessed by 3D CT evaluation.

This work reported the use and evaluation of direct 3DP porous polyethylene in middle- to large-sized cranial reconstructions. It evidently showed the bonding of implants to surrounding tissues which would result in the long-term stability and infection resistance of the implant.

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 demonstrate the feasibility of incremental sheet forming (ISF), using the most common variants, single-point incremental forming (SPIF) and two-point incremental forming (TPIF), to produce prototypes of customized cranial implants using a biocompatible polymer (ultrahigh molecular weight polyethylene, UHMWPE), ensuring an appropriate geometric accuracy and cost.

The cranial implant is designed based on computerized tomographies (CT) of the patient, converting them into a 3D model using the software InVesalius. To generate the toolpath for the forming operation computer-aided manufacturing (CAM) software is used. Once the cranial implant is manufactured, a 3D scanning system is used to determine the geometric deviation between the real part and the initial design.

The results corroborate that it is possible to successfully manufacture a customized cranial implant using ISF, being able to improve the geometric accuracy using the TPIF variant with a negative die.

This paper is one of the first research works in which a customized cranial implant is successfully manufactured using a flexible technology, ISF and a biocompatible polymer. The use of polymeric implants in cranioplasty is advantageous because of their lightweight, low heat conductivity and mechanical properties similar to bone. Furthermore, the cost of the implant has been calculated considering not only the raw materials and manufacturing time but also the environmental impact, revealing that it is a cheap process with a low lead-time.

This study aims to assess the design, manufacturing and surgical implantation of three-dimensional (3D) customized implants, including surgical preoperative planning, surgery and postoperative results, for cranioplasty along with zygomatic and orbital floor implants using additive manufacturing (AM) technics for a 23-year-old female who suffered from severe craniomaxillofacial trauma.

The skull biomodel was produced in polyamide while implants were made of Ti-6Al-4V alloy by AM.

The method enabled perfectly fitting implants and anatomical conformance with the craniomaxillofacial defect, providing complete healing for the patient. Surgical planning using a customized 3D polyamide biomodel was effective. This proved to be a powerful tool for medical planning and manufacturing of customized implants, as complete healing and good craniofacial aesthetic results were observed.

Satisfactory surgical procedures, regarding surgery time reduction and good craniofacial aesthetic results, were achieved. Furthermore, the 3D titanium customized implants represented a favorable alternative for the repair of craniomaxillofacial defects.

Aims to investigate medical rapid prototyping (medical RP) technology applications and methods based on reverse engineering (RE) and medical imaging data.

Medical image processing and RE are applied to construct three‐dimensional models of anatomical structures, from which custom‐made (personalized) medical applications are developed.

The investigated methods were successfully used for design and manufacturing of biomodels, surgical aid tools, implants, medical devices and surgical training models. More than 40 medical RP applications were implemented in Europe and Asia since 1999.

Medical RP is a multi‐discipline area. It involves in many human resources and requires high skills and know‐how in both engineering and medicine. In addition, medical RP applications are expensive, especially for low‐income countries. These practically limit its benefits and applications in hospitals.

In order to transfer medical RP into hospitals successfully, a good link and close collaboration between medical and engineering sites should be established. Moreover, new medical applications should be developed in the way that does not change the traditional approaches that medical doctors (MD) were trained, but provides solutions to improve the diagnosis and treatment quality.

The presented state‐of‐the‐art medical RP is applied for diagnosis and treatment in the following medical areas: cranio‐maxillofacial and dental surgery, neurosurgery, orthopedics, orthosis and tissue engineering. The paper is useful for MD (radiologists and surgeons), biomedical and RP/CAD/CAM engineers.

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.

During the repair of compound skull fractures or penetrating wounds to the brain, removal of significant portions of the skull may be required. Conventional prefabricated alloplastic implants require the use of complicated procedures during surgery, which can endanger a patient. Since prior rehearsals of the surgery are next to impossible, the surgery is usually complicated and lengthy. This paper aims to outline the importance of rapid prototyping (RP) in medicine, and also it details the use of RP for a cranioplastic surgery that was conducted in the South East Asian region. RP offers an easier way to design customized implants and manufacture them within a very short period. Rapid Prototyping can be used as an effective tool to generate complex 3D medical models from computed tomographic (CT) images. The models can be used for didactic purposes, as it helps the surgeons plan and rehearse the surgery well in advance. The RP prototype was used to successfully complete a cranioplastic surgery and realize the desired results. The operation time was also significantly reduced.

The purpose of this study is to suggest the joint use of computer-aided design (CAD) and additive manufacturing (AM) technology for the fabrication of custom-made moulds, designed for the manufacture of polymethyl methacrylate (PMMA) implants for cranio-maxillofacial reconstruction to reduce their fabrication time. Even though tailor-made skull prostheses with a high technological level and state-of-the-art materials are available in the market, they are not always accessible to the general population in developing countries.

Computed tomography data were handled to create a three-dimensional (3D) model of the injury of the patient, by reconstructing Digital Imaging and Communications in Medicine (DICOM) images into an Standard Tessellation Language (STL) file that was further used to design the corresponding implant using CAD software. Accordingly, a two-piece core and cavity moulds that replicated the implant geometry was also CAD designed. The 3D-CAD data were sent to an AM machine (fused deposition modelling) and the moulds were fabricated using polycarbonate as thermoplastic material. A reacting mixture to produce PMMA was poured directly into the fabricated moulds, and left to polymerise until cure. Finally, a clear bubble-free case of study PMMA implant was obtained.

The fabrication of CAD-designed moulds with AM, replacing the production of the injury model, resulted in the reduction of the lead-time in the manufacturing of PMMA around 45 per cent. Additionally, the implant showed better fit than the one produced by conventional process. The use of AM moulds for the fabrication of PMMA implants has demonstrated the reduction in lead-time, which potentially can reduce the waiting time for patients.

Currently, the demand of cranio-maxillofacial implants at only the Hospital General de México “Dr Eduardo Liceaga” (HGM) is 4,000 implants per year, and the average waiting time for each patient is between 5 and 10 weeks, including third-party services’ delays and the time needed to obtain the economical resources by the patient. Public hospitals in Mexico lack manufacturing facilities, so patients have to make use of laboratories abroad and most of the population have no access to them. The implementation of this suggested procedure in public hospitals may improve the accuracy of the implant, increase the number of patients attended per year (up to 83 per cent) and the reduction in waiting time can also reduce mortality and infection rates.

The authors of this paper suggest the joint use of CAD and AM technologies to significantly reduce the production time of PMMA implants by producing moulds rather than the injury model, maintaining the general terms and known steps of the process already established for PMMA implants.