The use of 3D printing technology in limb reconstruction. Inspirations and challenges.

The management of septic non-unions with associated bone necrosis is challenging, especially when the resulting bone defect after the debridement is extensile. Different techniques have been described in the literature for the treatment of these demanding cases, with the most prominent being free vascularized Fibular graft and bone transport with distraction osteogenesis principles. Recently, 3D printing technology has been increasingly utilized in many complex orthopaedic pathologies. However, the application of those advancements regarding septic non-unions with residual bone defect has not been previously studied. This study presents a novel 3D printing technique for the management of an infected critical bone deficit of the tibia. Queries, challenges and future perspectives concerning the recruiting of 3D printing technology in limb reconstruction are also being discussed. Clinical Evidence Level: IV.

How 3D printing and social media tackles the PPE shortage during Covid - 19 pandemic.

During the recent Covid-19 pandemic, additive Technology and Social Media were used to tackle the shortage of Personal Protective Equipment. A literature review and a social media listening software were employed to explore the number of the users referring to specific keywords related to 3D printing and PPE. Additionally, the QALY model was recruited to highlight the importance of the PPE usage. More than 7 billion users used the keyword covid or similar in the web while mainly Twitter and Facebook were used as a world platform for PPE designs distribution through individuals and more than 100 different 3D printable PPE designs were developed.

Cost Estimation of Polymeric Adsorbents.

One of the most promising techniques of recent research is adsorption. This technique attracts great attention in environmental technology, especially in the decontamination of water and wastewaters. A "hidden" point of the above is the cost of adsorbents. As can be easily observed in the literature, there is not any mention about the synthesis cost of adsorbents. What are the basic criteria with which an industry can select an adsorbent? What is the synthesis (recipe) cost? What is the energy demand to synthesize an efficient material? All of these are questions which have not been answered, until now. The reason for this is that the estimation of adsorbents' cost is relatively difficult, because too many cost factors are involved (labor cost, raw materials cost, energy cost, tax cost, etc.). In this work, the first estimation cost of adsorbents is presented, taking into consideration all of the major factors which influence the final value. To be more comparable, the adsorbents used are from a list of polymeric materials which are already synthesized and tested in our laboratory. All of them are polymeric materials with chitosan as a substrate, which is efficiently used for the removal of heavy metal ions.

Small-angle X-ray scattering (SAXS) and nitrogen porosimetry (NP): two novel techniques for the evaluation of urinary stone hardness.

PURPOSE: To evaluate urinary stones using small-angle X-ray scattering (SAXS) and nitrogen porosimetry (NP). Traditionally, stones are categorized as hard or soft based on their chemical composition. We hypothesized that stone hardness is associated not only with its chemical composition but also with its internal architecture. SAXS and NP are well-known techniques in material sciences. We tested whether SAXS and NP are applicable for evaluating human urinary stones and whether they provide information at the nanoscale level that could be useful in clinical practice. METHODS: Thirty endoscopically removed urinary stones were studied. Standard techniques for stone analysis were used to determine the stone composition. SAXS was used to evaluate the solid part of the stone by measuring the crystal thickness (T) and the fractal dimension (Dm/Ds), while NP was used to evaluate the porosity of the stone, i.e., the pore radius, pore volume, and specific surface area (SSA). RESULTS: All stones were successfully analyzed with SAXS and NP. Each stone demonstrated unique characteristics regarding T, Dm/Ds, pore radius, pore volume, and SSA. Significant differences in those parameters were seen among the stones with almost identical chemical compositions. The combination of high T, high SSA, low Dm/Ds, low pore volume, and low pore radius is indicative of a hard material and vice versa. CONCLUSIONS: SAXS and NP can be used to evaluate human urinary stones. They provide information on stone hardness based on their nanostructure characteristics, which may be different even among stones with similar compositions.