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Post-traumatic zygomatic osteotomy, fracture reduction, and orbital floor reconstruction pose many challenges for achieving a predictable, accurate, safe, and aesthetically pleasing result. This paper aims to describe the successful application of computer-aided design (CAD) and additive manufacturing (AM) to every stage of the process – from planning to surgery.

A multi-disciplinary team was used – comprising surgeons, prosthetists, technicians, and designers. The patient’s computed tomography scan data were segmented for bone and exported to a CAD software package. Medical models were fabricated using AM; for diagnosis, patient communication, and device verification. The surgical approach was modelled in the virtual environment and a custom surgical cutting guide, custom bone-repositioning guide, custom zygomatic implant, and custom orbital floor implant were each designed, prototyped, iterated, and validated using polymer AM prior to final fabrication using metal AM.

Post-operative clinical outcomes were as planned. The patient’s facial symmetry was improved, and their inability to fully close their eyelid was corrected. The length of the operation was reduced relative to the surgical team’s previous experiences. Post-operative scan analysis indicated a maximum deviation from the planned location for the largest piece of mobilised bone of 3.65 mm. As a result, the orbital floor implant which was fixed to this bone demonstrated a maximum deviation of 4.44 mm from the plan.

This represents the first application of CAD and AM to every stage of the process for this procedure – from diagnosis, to planning, and to surgery.

Computer-aided design and additive manufacture (CAD/AM) technologies are sufficiently refined and meet the necessary regulatory requirements for routine incorporation into the medical field, with long-standing application in surgeries of the maxillofacial and craniofacial regions. They have resulted in better medical care for patients and faster, more accurate procedures. Despite ever-growing evidence about the advantages of computer-aided planning, CAD and AM in surgery, detailed reporting on critical design decisions that enable methodological replication and the development and establishment of guidelines to ensure safety are limited. This paper aims to present a novel application of CAD and AM to a single-stage resection and reconstruction of fibrous dysplasia in the zygoma and orbit.

It is reported in sufficient fidelity to permit methods replication and design guideline developments in future cases, wherever they occur in the world. The collaborative approach included engineers, designers, surgeons and prosthetists to design patient-specific cutting guides and a custom implant. An iterative design process was used, until the desired shape and function were achieved, for both of the devices. The surgery followed the CAD plan precisely and without problems. Immediate post-operative subjective clinical judgements were of an excellent result.

At 19 months post-op, a CT scan was undertaken to verify the clinical and technical outcomes. Dimensional analysis showed maximum deviation of 4.73 mm from the plan to the result, while CAD-Inspection showed that the deviations ranged between −0.1 and −0.8 mm and that the majority of deviations were located around −0.3 mm.

Improvements are suggested and conclusions drawn regarding the design decisions considered critical to a successful outcome for this type of procedure in the future.

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 compare four different additive manufacturing (AM) processes to assess their suitability in the context of upper extremity splinting.

This paper describes the design characteristics and subsequent fabrication of six different wrist splints using four different AM processes: laser sintering (LS), fused deposition modelling (FDM), stereolithography (SLA) and polyjet material jetting via Objet Connex. The suitability of each process was then compared against competing designs and processes from traditional splinting. The splints were created using a digital design workflow that combined recognised clinical best practice with design for AM principles.

Research concluded that, based on currently available technology, FDM was considered the least suitable AM process for upper extremity splinting. LS, SLA and material jetting show promise for future applications, but further research and development into AM processes, materials and splint design optimisation is required if the full potential is to be realised.

Unlike previous work that has applied AM processes to replicate traditional splint designs, the splints described are based on a digital design for AM workflow, incorporating novel features and physical properties not previously possible in clinical splinting. The benefits of AM for customised splint fabrication have been summarised. A range of AM processes have also been evaluated for splinting, exposing the limitations of existing technology, demonstrating novel and advantageous design features and opportunities for future research.

THE NINETIENTH ANNIVERSARY of Sean O'Casey's birth and the recent acquisition by the New York Public Library of the papers of his literary estate afford an opportunity to view, once more, the remarkable achievements of a dramatist of universal distinction. A passionate believer in the cause of man's dignity and freedom, whose plays touched off riots and sparked off controversies, whose works wrung the beauty and passion and heartaches from the experiences of everyday life and ‘whose lips were royally touched’—to quote J. C. Trewin's recent colourful phrase—O'Casey was, with Shaw, one of the few incomparably great playwrights of the present century. Not without his detractors: one critic's jibe that O'Casey is ‘an extremely overrated writer with two or three competent Naturalist plays to his credit, followed by a lot of ideological bloat and embarrassing bombast’ is the kind of factitious reaction one expects from critically immature minds. Shaw's plays, at first, were slighted, but they survived, and today are flourishing; predictably, O'Casey's will enjoy a similar fate. O'Casey is a world dramatist in the widest sense, because he viewed the theatre in the same epic way as Shakespeare and the rest of the Elizabethans.

If a seller fails to deliver the correct quantity, the buyer may reject the goods in accordance with the Sale of Goods Act 1979, section 30(1). The nature of this right to reject is unclear, and whether breach by short delivery will suffice to terminate the contract is also unclear. The purpose of this paper is to clarify this area of law.

The focus is on the combined case‐law and academic commentary on the topic of short delivery, and the broader issue of termination.

The paper suggests that breach by short delivery does terminate the contract. It suggests that the right to cure cannot provide an entirely satisfactory response for victims of short delivery. The paper also proposes a reform of the Sale of Goods Act 1979 to take this into account.

This research mainly focused on the current legal position. Further research on the historical development of the rules on short delivery, which were crystallised in the Sale of Goods Act 1893, will provide valuable insights into this area of law.

The proposal for reform could have a practical benefit in terms of protecting buyers from the danger of short delivery, by providing them with a more secure remedy than what appears to be currently available.

To the extent of the author's knowledge, this is the first dedicated analysis of short delivery in the literature.

The South African wool industry is integral to the country's agricultural sector, particularly sheep farming and wool production. Small-scale farmers play a vital role in this industry and contribute to employment and food security in rural communities. However, these farmers face numerous challenges, including a lack of funding, poor farming practices and difficulty selling their wool at fair prices. This study aims to address these challenges, the University of Free State launched a wool value chain project for small-scale farmers.

In this project, one of the studies conducted assessed the effectiveness of different detergents suitable for traditional wool scouring methods for small-scale farmers who lack access to sophisticated machinery. The investigation was conducted by scouring 160 wool samples using three different detergents and filtered water as a control. The wool samples were then evaluated for their cleanliness, brightness and fibre properties through a combination of scanning electron microscopy, spectrophotometry and statistical analysis at different scouring times (3, 10, 15 and 20 min, respectively).

The results showed that the combination of scouring time and the type of scouring solution used could significantly impact wool quality. It was found that using a combination of standard detergent or Woolwash as a scouring solution with a scouring time of 10–15 min resulted in the best outcome in terms of fibre property, wool colour and scouring loss.

This study demonstrated that traditional wool scouring methods could be an option for small-scale farmers and anyone who want to learn how to scour wool without expensive machinery to make wool products.

Recognizing the need to build global-minded citizens, higher education institutions are increasingly trying to find ways to leverage their international programs to develop students’ intercultural competence. The MA in global leadership at Royal Roads University, Canada, created an international partnership in Ecuador that serves to go beyond the traditional student study abroad or service learning focus and instead focuses on developing competencies of global mindedness and strategic relationships. In this chapter, we present an analysis of how an international student group engaged in building dynamic partnerships within a Global South country to create change for sustainable development initiatives of mutual concern. Through a case example, we describe how these partnerships evolved and adapted in ways that enhanced the learning needs of the students while simultaneously supporting the development of new educational opportunities for Ecuadorians. To illustrate, this chapter delineates the activities that members of the program undertook to connect and develop a mutuality of relationship across diverse stakeholders in Ecuador. The authors analyze this network-building process from the perspective of cultural context, building trust and influence, and responding to social development needs of host communities.