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To develop a computer‐assisted prefabricated implant design and manufacturing system to improve the esthetic outcome in chin surgery.

Design methods for medical rapid prototyping (RP) of custom‐fabricated chin augmentation implant are presented in this paper. After a careful preoperative planning based on cephalometric tracing for esthetic assessment, helical computed tomography data were used to create a three‐dimensional model of the deficient mandible. Based on these data, the inner surface of the prosthesis was designed to fit the bone surface exactly. The outer geometry was generated from a dried human mandible to create anatomically correct shape prosthesis. The inner and outer surfaces were then connected, and a solid model resulted. A RP system was used for production of the physical models. The surgical planning was performed using the implants and skull models. The resulting SLA implant is used for the production of a mold, which is used to cast the titanium part. Three patients with a congenital small chin or a small and asymmetric mandible underwent reconstruction with individual prefabricated implant. Mean follow‐up period was 1.5 years.

This approach showed significant results in chin augmentation. Compared with traditional methods, the intra‐operative fit was excellent. The operating time was reduced. Postoperatively, the patients experienced the restoration of a natural chin contour, so the esthetic outcome was pleasing. Over the mean follow‐up period of 1.5 years, there were no complications and no implant had to be removed. Long‐term excellent esthetic outcomes by using this new technique have recently been reported.

The methods described above suffer from certain limitations. The registration of the mandible template to create the augmentation image requires high skills of the designer. In addition, the use of RP model in preoperative preparation is expensive.

This method not only demonstrates the significant progress in the reconstruction of chin defects using CAD/CAM RP and RT, compared with the conventional methods of chin augmentation surgery, but also provides natural geometrical prosthesis contour design and accurate fabrication and precise fitting of the prosthesis. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

This clinical case demonstrated the potential value of CAD/CAM and RP‐based custom fitted and anatomically correct shape prosthesis fabrication and presurgical planning in craniofacial surgery.

This paper describes computer‐aided design (CAD) and rapid prototyping (RP) systems for the fabrication of maxillofacial implant.

Design methods for medical RP of custom‐fabricated are presented in this paper. Helical computed tomography (CT) data were used to create a three‐dimensional model of the patient skull. Based on these data, the individual shape of the implant was designed in CAD environment and fabricate by RP process. One patient with a large mandible defect underwent reconstruction with individual prefabricated implant resulting from initial surgical failure with hand contoured reconstruction plate.

Results shows that the custom made implant fit well the defect. Overall, excellent mandible symmetry and stability were achieved with the custom made implants. The patient was able to eat. There was no saliva drooling after the reconstruction. The operating time was reduced.

The methods described above suffer from the expensive cost of RP technique.

This method allows accurate fabrication of the implant. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

The method improves the reconstructive surgery and reduces the risk of a second intervention, and the psychological stress of the patient will be eliminated.

The purpose of this paper is to fabricate and characterize osteochondral beta‐tricalcium phosphate/collagen scaffold with bio‐inspired design by ceramic stereolithography (CSL) and gel casting.

Histological analysis was applied to explore the morphological characteristics of the transitional structure between the bone and the cartilage. The acquired data were used to design biomimetic biphasic scaffolds, which include the bone phase, cartilage phase, and their transitional structure. The engineered scaffolds were fabricated from β‐TCP‐collagen by CSL and gel casting. The cartilage phase was added to the ceramic phase by gel‐casting and freeze drying.

The resulting ceramic scaffolds were composed of a bone phase with the following properties: 700‐900 μm pore size, 200‐500 μm interconnected pores size, 50‐65 percent porosity, fully interconnected, ∼12 Mpa compressive strength. A suitable binding force between cartilage phase and ceramic phase was achieved by physical locking that was created by the biomimetic transitional structure. Cellular evaluation showed satisfactory results.

This study is the first try to apply CSL to fabricate biological implants with β‐TCP and type‐I collagen. There are still some defects in the composition of the slurry and the fabrication process.

This strategy of osteochondral scaffold fabrication can be implemented to construct an osteochondral complex that is similar to native tissue.

The CSL technique is highly accurate, as well as biologically secure, when fabricating ceramic tissue engineering scaffolds and may be a promising method to construct hard tissue with delicate structures. The present strategy enhances the versatility of scaffold fabrication by RP.

This paper aims to describe computer‐aided design and rapid prototyping (RP) systems for the preoperative planning and fabrication of custom‐made implant.

A patient with mandible defect underwent reconstruction using custom‐made implant. 3D models of the patient's skull are generated based on computed tomography image data. After evaluation of the 3D reconstructed image, it was identified that some bone fragment was moved due to the missing segment. During the implant design process, the correct position of the bone fragment was defined and the geometry of the custom‐made implant was generated based on mirror image technique and is fabricated by a RP machine. Surgical approach such as preoperative planning and simulation of surgical procedures was performed using the fabricated skull models and custom‐made implant.

Results show that the stereolithography model provided an accurate tool for preoperative, surgical simulation.

The methods described above suffer from the expensive cost of RP technique.

This method allows accurate fabrication of the implant. The advantages of using this technique are that the physical model of the implant is fitted on the skull model so that the surgeon can plan and rehearse the surgery in advance and a less invasive surgical procedure and less time‐consuming reconstructive and an adequate esthetic can result.

The method improves the reconstructive surgery and reduces the risk of a second intervention, and the psychological stress of the patient will be eliminated.

Vehicle allocation problems (VAPs), which are frequently confronted in many transportation activities, primarily including but not limited to full truckload freight transportation operations, induce a significant economic impact. Despite the increasing academic attention to the field, literature still fails to match the needs of and opportunities in the growing industrial practices. In particular, the literature can grow upon the ideas on sustainability, Industry 4.0 and collaboration, which shape future practices not only in logistics but also in many other industries. This review has the potential to enhance and accelerate the development of relevant literature that matches the challenges confronted in industrial problems. Furthermore, this review can help to explore the existing methods, algorithms and techniques employed to address this problem, reveal directions and generate inspiration for potential improvements.

This study provides a literature review on VAPs, focusing on quantitative models that incorporate any of the following emerging logistics trends: sustainability, Industry 4.0 and logistics collaboration.

In the literature, sustainability interactions have been limited to environmental externalities (mostly reducing operational-level emissions) and economic considerations; however, emissions generated throughout the supply chain, other environmental externalities such as waste and product deterioration, or the level of stakeholder engagement, etc., are to be monitored in order to achieve overall climate-neutral services to the society. Moreover, even though there are many types of collaboration (such as co-opetition and vertical collaboration) and Industry 4.0 opportunities (such as sharing information and comanaging distribution operations) that could improve vehicle allocation operations, these topics have not yet received sufficient attention from researchers.

The scientific contribution of this study is twofold: (1) This study analyses decision models of each reviewed article in terms of decision variable, constraint and assumption sets, objectives, modeling and solving approaches, the contribution of the article and the way that any of sustainability, Industry 4.0 and collaboration aspects are incorporated into the model. (2) The authors provide a discussion on the gaps in the related literature, particularly focusing on practical opportunities and serving climate-neutrality targets, carried out under four main streams: logistics collaboration possibilities, supply chain risks, smart solutions and various other potential practices. As a result, the review provides several gaps in the literature and/or potential research ideas that can improve the literature and may provide positive industrial impacts, particularly on how logistics collaboration may be further engaged, which supply chain risks are to be incorporated into decision models, and how smart solutions can be employed to cope with uncertainty and improve the effectiveness and efficiency of operations.

The last decade has seen major advances in rapid prototyping (RP), with it becoming a multi‐disciplinary technology, crossing various research fields, and connecting continents. Process and material advancements open up new applications and manufacturing (through RP) is serving non‐traditional industries. RP technology is used to support rapid product development (RPD). The purpose of this paper is to describe how the Integrated Product Development research group of the Central University of Technology, Free State, South Africa is applying various CAD/CAM/RP technologies to support a medical team from the Grootte Schuur and Vincent Palotti hospitals in Cape Town, to save limbs – as a last resort at a stage where conventional medical techniques or practices may not apply any longer.

The paper uses action research to justify the proposal of a new method to use CAD/CAM/RP related technologies to substitute lost/damaged bone regions through the use of CT to CAD to.STL manipulation.

A case study where RP related technologies were used to support medical product development for a patient with severe injuries from a road accident is discussed.

The paper considers current available technologies, and discusses new advancements in direct metal freeform fabrication, and its potential to revolutionise the medical industry.

This paper aims to develop 3D-printed customized padding to increase pressure at the zero pressure region. This padding is specifically intended for facial areas with complex contours in pressure therapy treatment of hypertrophic scars.

To carry out this study, a full-face head garment was fabricated by a local occupational therapist, and pressure measurements were conducted to establish the pressure exerted by this head garment and to determine the zero pressure region. Furthermore, an additional manufacturing method was used to construct customized padding, and pressure measurements were performed to measure the pressure exerted after application of this customized padding.

The results reveal that 3D-printed customized padding can increase pressure at the zero pressure region, which occurs on complex contour surfaces with a spatial gap because of non-contact of the head garment and facial surfaces.

This paper suggests that an additive manufacturing method using 3D printing is capable of producing accurate, functional and low-cost medical parts for rehabilitation. Moreover, the 3D-printed padding fabricated by additive manufacturing assists in generating optimal pressure, which is necessary for effective pressure therapy.

Digital design using 3D scanning, computer-aided design and 3D printing is capable of designing and producing properly fitting, customized padding that functions to increase pressure from zero to an acceptable pressure range required for pressure therapy.

To fabricate the self‐hardening calcium phosphate composite scaffolds with controlled internal pore architectures using rapid prototyping (RP) techniques and investigate their in vitro bone tissue engineering responses.

The three‐dimensionally interconnected pores in scaffolds can facilitate sufficient supply of blood, oxygen and nutrients for the ingrowth of bone cells, tissue regeneration, and vascularization. It is essential for bone tissue engineering to provide an accurate control over the scaffolds material, porosity, and internal pore architectures. Negative image of scaffold was designed and epoxy resin molds were fabricated on sterolithography apparatus. Calcium phosphate cement slurry was cast in these molds. After self‐hardening, the molds were removed by pyrolysis and the resulting scaffolds were obtained.

Eight scaffolds with 54.45 percent porosity were tested on an Instron machine. The average compressive strength measured was 5.8±0.8 Mpa. Cytotoxicity and cell proliferation studies were conducted with rabbit osteoblast. Results showed that these scaffolds were non‐toxic and displayed excellent cell growth during the 2 weeks of in vitro culture.

The resulting scaffolds inherited errors and defects from the molds, such as cracks and dimensional changes.

The present method enhances the versatility of scaffold fabrication by RP. It is capable of reproducibly fabricating scaffolds from a variety of biomaterials.

The purpose of this paper is to describe two different approaches for manufacturing pre-formed titanium meshes to assist prosthetically guided bone regeneration of atrophic maxillary arches. Both methods are based on the use of additive manufacturing (AM) technologies and aim to limit at the minimal intervention the bone reconstructive surgery by virtual planning the surgical intervention for dental implants placement.

Two patients with atrophic maxillary arches were scheduled for bone augmentation using pre-formed titanium mesh with particulate autogenous bone graft and alloplastic material. The complete workflow consists of four steps: three-dimensional (3D) acquisition of medical images and virtual planning, 3D modelling and design of the bone augmentation volume, manufacturing of biomodels and pre-formed meshes, clinical procedure and follow up. For what concerns the AM, fused deposition modelling (FDM) and direct metal laser sintering (DMLS) were used.

For both patients, a post-operative control CT examination was scheduled to evaluate the progression of the regenerative process and verify the availability of an adequate amount of bone before the surgical intervention for dental implants placement. In both cases, the regenerated bone was sufficient to fix the implants in the planned position, improving the intervention quality and reducing the intervention time during surgery.

A comparison between two novel methods, involving AM technologies are presented as viable and reproducible methods to assist the correct bone augmentation of atrophic patients, prior to implant placement for the final implant supported prosthetic rehabilitation.