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Integration of diverse materials into 3D ordered structures is urgently required for advanced manufacture owing to increase in demand for high-performance products. Most additive manufacturing techniques mainly focus on simply combining different equipment, while interfacial binding of distinctive materials remains a fundamental problem. Increasing studies on macroscopic supramolecular assembly (MSA) have revealed efficient interfacial interactions based on multivalency of supramolecular interactions facilitated by a "flexible spacing coating." To demonstrate facile fabrication of 3D heterogeneous ordered structures, the combination of MSA and magnetic field-assisted alignment has been developed as a new methodology for in situ integration of a wide range of materials, including elastomer, resin, plastics, metal, and quartz glass, with modulus ranging from tens of MPa to over 70 GPa. Assembly of single material, coassembly of two to four distinctive materials, and 3D alignment of "bridge-like" and "cross-stacked" heterogeneous structures are demonstrated. This methodology has provided a new solution to mild and efficient assembly of multiple materials at the macroscopic scale, which holds promise for advanced fabrication in fields of tissue engineering, electronic devices, and actuators., Competing Interests: The authors declare no conflict of interest., (© 2020 The Authors. Published by Wiley‐VCH GmbH.)

Microfluidic-based tissue-on-a-chip devices have generated significant research interest for biomedical applications, such as pharmaceutical development, as they can be used for small volume, high throughput studies on the effects of therapeutics on tissue-mimics. Tissue-on-a-chip devices are evolving from basic 2D cell cultures incorporated into microfluidic devices to complex 3D approaches, with modern designs aimed at recapitulating the dynamic and mechanical environment of the native tissue. Thus far, most tissue-on-a-chip research has concentrated on organs involved with drug uptake, metabolism and removal (e.g., lung, skin, liver, and kidney); however, models of the drug metabolite target organs will be essential to provide information on therapeutic efficacy. Here, we develop an osteogenesis-on-a-chip device that comprises a 3D environment and fluid shear stresses, both important features of bone. This inexpensive, easy-to-fabricate system based on a polymerized High Internal Phase Emulsion (polyHIPE) supports proliferation, differentiation and extracellular matrix production of human embryonic stem cell-derived mesenchymal progenitor cells (hES-MPs) over extended time periods (up to 21 days). Cells respond positively to both chemical and mechanical stimulation of osteogenesis, with an intermittent flow profile containing rest periods strongly promoting differentiation and matrix formation in comparison to static and continuous flow. Flow and shear stresses were modeled using computational fluid dynamics. Primary cilia were detectable on cells within the device channels demonstrating that this mechanosensory organelle is present in the complex 3D culture environment. In summary, this device aids the development of 'next-generation' tools for investigating novel therapeutics for bone in comparison with standard laboratory and animal testing., (Copyright © 2020 Bahmaee, Owen, Boyle, Perrault, Garcia-Granada, Reilly and Claeyssens.)

In this work, we show how miniature step gauges featuring unidirectional and bidirectional lengths can be used to assess the performance of 3D optical scanners as well as the accuracy of novel Additive Manufacturing (AM) processes. A miniature step gauge made of black polyphenylene sulfide (PPS) was used for the performance verification of three different optical scanners: a structured light scanner (SLS), a laser line scanner (LLS), and a photogrammetry-based scanner (PSSRT), having comparable resolutions and working volumes. Results have shown a good agreement between the involved scanners, with errors below 5 μm and expanded uncertainties below 10 μm. The step gauge geometry due to the bidirectional lengths, highlights that there is a different interaction between the optical properties of the step gauge under measurement and each optical instrument involved and this aspect has to be considered in the uncertainty budget. The same geometry, due to its great significance in the detection of systematic errors, was used, as a novelty, to evaluate the accuracy of Lithography-based Ceramics Manufacturing (LCM), a proprietary additive manufacturing technology used for the fabrication of medical implants. In particular, two miniature step gauges made of Tricalcium Phosphate (TCP) were produced. Measurements conducted with the SLS scanner were characterized by a negligible error and by an uncertainty of about 5 μm. Deviations of the manufactured step gauges with respect to the Computer Aided Designed (CAD) model were comprised between ±50 μm, with positive deviations in the order of 100 μm on vertical sides. Differences in the order of 50 μm between the two step gauges were registered., Competing Interests: The authors declare no conflict of interest.

• Conventional diamond lattices are distorted to produce novel anisotropic structures. • These forms allow investigation of the anisotropy of lattices in additive manufacture. • No mechanical anisotropy found in electron beam melted Ti6Al4V lattices. With advances in additive manufacturing methods for metals with defined, complex shapes, the investigation of metallic lattice materials (metals with significant porosity and a regular arrangement of the solid, frequently in the form of thin struts) has become more common. These materials may be highly optimized for particular applications, and can show mechanical behaviors not displayed by other solids; for this reason, they are often used as routes to create mechanical metamaterials. However, thermal history experienced by the material in this novel process affects the microstructure produced, in particular making it highly directional. While understood for dense parts, the behavior in porous materials, where the structure itself can alter the thermal history experienced locally, is more ambiguous. This paper examines the mechanical properties of titanium alloy lattices based on the widely-used diamond structure, fabricated by electron beam melting (EBM). Related forms, distorted to alter the symmetry (from cubic to tetragonal) are tested and compared to more clearly elucidate the anisotropy in their mechanical properties. For the distorted lattices, the elastic modulus along the stretched direction is increased by a factor of over three, and the yield strength is more than doubled. In both lattices the orientation is found to have a much less significant effect than seen for bulk materials, likely to be due to the high proportion of the lattices that are influenced by free surface. [ABSTRACT FROM AUTHOR]

In comparison to through-knee amputees the outcomes for above-the-knee amputees are relatively poor; based on this novel techniques have been developed. Most current percutaneous implant-based solutions for transfemoral amputees make use of high stiffness intramedullary rods for skeletal fixation, which can have risks including infection, femoral fractures, and bone resorption due to stress shielding. This work details the cadaveric testing of a short, cortical bone stiffness-matched subcutaneous implant, produced using additive manufacture, to determine bone implant micromotion and push-out load. The results for the micromotions were all <20 μm and the mean push-out load was 2,099 Newtons. In comparison to a solid control, the stiffness-matched implant exhibited significantly higher micromotion distributions and no significant difference in terms of push-out load. These results suggest that, for the stiffness-matched implant at time zero, osseointegration would be facilitated and that the implant would be securely anchored. For these metrics, this provides justification for the use of a short-stem implant for transfemoral amputees in this subcutaneous application. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2104-2111, 2019., (© 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

The repair of critical-size bone defect remains a challenge for orthopedic surgeons. With the advent of an aging society and their accompanying chronic diseases, it is becoming more difficult to treat bone defects, especially large segmental bone defects that are caused by trauma, tumors, infections, and congenital malformations. New materials and technologies need to be developed to address these conditions. 3D bioprinting is a novel technology that bridges the biomaterial and living cells and is an important method in tissue engineering projects. 3D bioprinting has the advantages of replacing or repairing damaged tissue and organs. The progress in material science and 3D printing devices make 3D bioprinting a technology which can be used to create various scaffolds with a large range of advanced material and cell types. However, in regard to the widespread use of bioprinting, biosafety, immunogenicity and rising costs are rising to be concerned. This article reviews the developments and applications of 3D bioprinting and highlights newly applied techniques and materials and the recent achievements in the orthopedic field. This paper also briefly reviews the difference between the methods of 3D bioprinting. The challenges are also elaborated with the aim to research materials, manufacture scaffolds, promote vascularization and maintain cell viability.

The rise of antibiotic resistant bacterial species is driving the requirement for medical devices that minimise infection risks. Antimicrobial functionality may be achieved by modifying the implant design to incorporate a reservoir that locally releases a therapeutic. For this approach to be successful it is critical that mechanical functionality of the implant is maintained. This study explores the opportunity to exploit the design flexibilities possible using additive manufacturing to develop porous lattices that maximise the volume available for drug loading while maintaining load-bearing capacity of a hip implant. Eight unit cell types were initially investigated and a volume fraction of 30% was identified as the lowest level at which all lattices met the design criteria in ISO 13314. Finite element analysis (FEA) identified three lattice types that exhibited significantly lower displacement (10-fold) compared with other designs; Schwartz primitive, Schwartz primitive pinched and cylinder grid. These lattices were additively manufactured in Ti-6Al-4V using selective laser melting. Each design exceeded the minimum strength requirements for orthopaedic hip implants according to ISO 7206-4. The Schwartz primitive (Pinched) lattice geometry, with 10% volume fill and a cubic unit cell period of 10, allowed the greatest void volume of all lattice designs whilst meeting the fatigue requirements for use in an orthopaedic implant (ISO 7206-4). This paper demonstrates an example of how additive manufacture may be exploited to add additional functionality to medical implants., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Lanthanide ions have special light emission, which can occur through descending and ascending energy conversion. Ascending energy conversion is especially interesting for bioapplications because excitation in the infrared region does not excite biomolecules and therefore does not interfere in detection, not to mention that it penetrates deeper in the skin. Here, we synthesized yttrium and aluminum oxide doped with Yb3+and Er3+ions via the non-hydrolytic sol-gel methodology. The doped matrix was incorporated and dispersed over a polyamide membrane obtained by Additive Manufacturing. X-ray diffraction revealed that a mixture of yttrium aluminum monoclinic and garnet phases emerged. Upon excitation at 980 nm in the Yb3+ion, the Er3+ presented more intense emission as a function of the laser power, which favored red emission. The intensities of the bands corresponding to the 4S3/2 → 4I15/2 (563 nm) and 5F9/2 → 4I15/2 (660 nm) transitions involved the absorption of two photons. The oxide incorporated into the polyamide membrane presented the same behavior. After coating with polyetherimide, the latter system was resistant to 5.1 W laser, which paves the way for new applications.

Background: The repair of large bone defects remains challenging for orthopaedic surgeons. Bone grafting remains the method of choice; such grafts fill spaces and enhance bone repair. Therapeutic agents also aid bone healing. The objective of this study is to develop a composite bioactive scaffold composed of polylactide-coglycolide (PLGA) and tricalcium phosphate (TCP) (the basic carrier) incorporating osteogenic, bioactive magnesium metal powder (Mg)., Method: Porous PLGA/TCP scaffolds incorporating Mg were fabricated using a low-temperature rapid-prototyping process. We term the PLGA/TCP/Mg porous scaffold (hereafter, PPS). PLGA/TCP lacking Mg served as the control material when evaluating the efficacy of PPS. A total of 36 New Zealand white rabbits were randomly divided into blank, PLGA/TCP (P/T) and PPS group, with 12 rabbits in each group. We established bone defects 15 mm in length in rabbit radii to evaluate the in vivo osteogenic potential of the bioactive scaffold in terms of the direct controlled release of osteogenic Mg ion during in vivo scaffold degradation. Radiographs of the operated radii were taken immediately after implantation and then at 2, 4, 8 and 12 weeks. Micro-computed tomography of new bone formation and remaining scaffold and histological analysis were performed at 4, 8, 12 weeks after operation., Results: X-ray imaging performed at weeks 4, 8 and 12 post-surgery revealed more newly formed bone within defects implanted with PPS and PLGA/TCP scaffolds than blank group ( p < 0.05 ). And micro-computed tomography performed at weeks 4 and 8 after surgery revealed more newly formed bone within defects implanted with PPS scaffolds than PLGA/TCP scaffolds ( p  < 0.05). Histologically, the PPS group had more newly mineralized bone than controls ( p  < 0.05). The increases in new bone areas (total implant regions) in the PPS and PLGA/TCP groups were 19.42% and 5.67% at week 4 and 48.23% and 28.93% at week 8, respectively. The percentages of remaining scaffold material in total implant regions in the PPS and PLGA/TCP groups were 53.30% and 7.65% at week 8 and 20.52% and 2.70% at week 12, respectively., Conclusion: Our new PPS composite scaffold may be an excellent orthopaedic substitute; it exhibits good biocompatibility and may potentially have clinical utility., Translational Potential of This Article: Magnesium and beta-tricalcium phosphate had osteoinduction. It is significant to print a novel bone composite scaffold with osteoinduction to repair segmental bone defects. This study evaluated efficacy of PPS in the rabbit radius segmental bone defect model. The results showed that the novel scaffold with good biocompatibility may be an excellent graft and potentially have clinical utility.

The aim of this study is to assess the additive manufacture of morphometric models of healthy and diseased coronary arteries. Using a dissected porcine coronary artery, a model was developed with the use of computer aided engineering, with splines used to design arteries in health and disease. The model was altered to demonstrate four cases of stenosis displaying varying severity, based on published morphometric data available. Both an Objet Eden 250 printer and a Solidscape 3Z Pro printer were used in this analysis. A wax printed model was set into a flexible thermoplastic and was valuable for experimental testing with helical flow patterns observed in healthy models, dominating the distal LAD (left anterior descending) and left circumflex arteries. Recirculation zones were detected in all models, but were visibly larger in the stenosed cases. Resin models provide useful analytical tools for understanding the spatial relationships of blood vessels, and could be applied to preoperative planning techniques, but were not suitable for physical testing. In conclusion, it is feasible to develop blood vessel models enabling experimental work; further, through additive manufacture of bio-compatible materials, there is the possibility of manufacturing customized replacement arteries., Competing Interests: The authors declare no conflict of interest.

In this study, we present a novel approach towards the straightforward, rapid, and low-cost development of biomimetic composite scaffolds for tissue engineering strategies. The system is based on the additive manufacture of a computer-designed lattice structure or framework, into which carbon fibers are subsequently knitted or incorporated. The 3D-printed lattice structure acts as support and the knitted carbon fibers perform as driving elements for promoting cell colonization of the three-dimensional construct. A human mesenchymal stem cell (h-MSC) conditioned medium (CM) is also used for improving the scaffold's response and promoting cell adhesion, proliferation, and viability. Cell culture results-in which scaffolds become buried in collagen type II-provide relevant information regarding the viability of the composite scaffolds used and the prospective applications of the proposed approach. In fact, the advanced composite scaffold developed, together with the conditioned medium functionalization, constitutes a biomimetic stem cell niche with clear potential, not just for tendon and ligament repair, but also for cartilage and endochondral bone formation and regeneration strategies., Competing Interests: Authors declare that no conflicting interests affected this research. Authors declare that no conflicting interests affected the objective presentation and description of results.

Objective: To assess the trueness and precision of copy denture templates produced using traditional methods and 3D printing., Material and Methods: Six copies of a denture were made using: 1. Conventional technique with silicone putty in an impression tray (CT). 2. Conventional technique with no impression tray (CNT). 3. 3D scanning and printing (3D). Scan trueness and precision was investigated by scanning a denture six times and comparing five scans to the sixth. Then the scans of the six CT, CNT and 3D dentures were compared by aligning, in turn, the copies of each denture to the scanned original. Outcome measures were the mean surface-to-surface distance, standard deviation of that distance and the maximum distance. Student's unpaired t-tests with Bonferroni correction were used to analyse the results., Results: The repeated scans of the original denture showed a scan trueness of 0.013mm (SD 0.002) and precision of 0.013mm (SD 0.002). Trueness: CT templates, 0.168mm (0.047), CNT templates 0.195mm (0.034) and 3D 0.103mm (0.021). Precision: CT templates 0.158mm (0.037), CNT 0.233mm (0.073), 3D 0.090mm (0.017). For each outcome measure the 3D templates demonstrated an improvement which was statistically significant (p⟨0.05)., Conclusions: 3D printed copy denture templates reproduced the original with greater trueness and precision than conventional techniques., (Copyright© 2017 Dennis Barber Ltd.)

Patient-centric medicine is a derivative term for personalised medicine, whereby the pharmaceutical product provides the best overall benefit by meeting the comprehensive needs of the individual; considering the end-user from the beginning of the formulation design process right through development to an end product is a must. One way in which to obtain personalised medicines, on-site and on-demand is by three-dimensional printing (3DP). The aim of this study was to investigate the influence of the shape, size and colour of different placebo 3D printed tablets (Printlets™) manufactured by fused deposition modelling (FDM) 3DP on end-user acceptability regarding picking and swallowing. Ten different printlet shapes were prepared by 3DP for an open-label, randomised, exploratory pilot study with 50 participants. Participant-reported outcome (PRO) and researcher reported outcome (RRO) were collected after picking and swallowing of selected printlet geometries including sphere, torus, disc, capsule and tilted diamond shapes. The torus printlet received the highest PRO cores for ease of swallowing and ease of picking. Printlets with a similar appearance to conventional formulations (capsule and disc shape) were also found to be easy to swallow and pick which demonstrates that familiarity is a critical acceptability attribute for end-users. RRO scores were in agreement with the PRO scores. The sphere was not perceived to be an appropriate way of administering an oral solid medicine. Smaller printlet sizes were found to be preferable; however it was found that the perception of size was driven by the type of shape. Printlet colour was also found to affect the perception of the end-user. Our study is the first to guide the pharmaceutical industry towards developing patient-centric medicine in different geometries via 3DP. Overall, the highest acceptability scores for torus printlets indicates that FDM 3DP is a promising fabrication technology towards increasing patient acceptability of solid oral medicines., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Selective laser sintering (SLS) 3-dimensional printing is currently used for industrial manufacturing of plastic, metallic and ceramic objects. To date there have been no reports on the use of SLS to fabricate oral drug loaded products; therefore, the aim of this work was to explore the suitability of SLS printing for manufacturing medicines. Two thermoplastic pharmaceutical grade polymers, Kollicoat IR (75% polyvinyl alcohol and 25% polyethylene glycol copolymer) and Eudragit L100-55 (50% methacrylic acid and 50% ethyl acrylate copolymer), with immediate and modified release characteristics respectively, were selected to investigate the versatility of a SLS printer. Each polymer was investigated with three different drug loadings of paracetamol (acetaminophen) (5, 20 and 35%). To aid the sintering process, 3% Candurin ® gold sheen was added to each of the powdered formulations. In total, six solid formulations were successfully printed; the printlets (3D printed tablets) were robust, and no evidence of drug degradation was observed. In biorelevant bicarbonate dissolution media, the Kollicoat formulations showed pH-independent release characteristics, with the release rate dependent on the drug content. In the case of the Eudragit formulations, these showed pH-dependent, modified-release profiles independent of drug loading, with complete release being achieved over 12h. In conclusion, this work has demonstrated that SLS is a versatile and practical 3D printing technology which can be applied to the pharmaceutical field, thus widening the armamentarium of 3D printing technologies available for the manufacture of modern medicines., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Additive manufacturing (AM) technologies enable greater geometrical design freedom compared with subtractive processes. This flexibility has been used to manufacture patient-matched implants. Although the advantages of AM are clear, the optimization at each process stage is often understated. Here we demonstrate that surface finishing of selective laser melted (SLM) implants significantly alters topography, which has implications for cellular and biofilm adhesion. Hot isostatic pressing of as-fabricated Ti-6Al-4V implants was shown to reduce porosity (1.04 to 0.02%) and surface roughness (34 ± 8 to 22 ± 3 μm). Despite these surface changes, preosteoblasts exhibited a similar viability and proliferation after 7 days of culture. Contrastingly, sandblasting and polishing significantly reduced cellular activity and increased cytotoxicity. Bacterial specimens (S taphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa ) adhered more homogeneously to sandblasted implants compared with other treatments. This suggests that sandblasting may place the implant at risk of infection and reduce the strength of interaction with the surrounding soft tissues. The ability to tune the adhesion of cells to additively manufactured Ti-6Al-4V implants using postprocessing methods was demonstrated. Because the degree of tissue integration required of implants is application specific, these methods may be useful to tailor osseointegration. However, surface competition between mammalian and bacterial cells remains a challenge.

The aim of this study was to manufacture 3D printed tablets (printlets) from enteric polymers by single filament fused deposition modeling (FDM) 3D printing (3DP). Hot melt extrusion was used to generate paracetamol-loaded filaments from three different grades of the pharmaceutical excipient hypromellose acetate succinate (HPMCAS), grades LG, MG and HG. One-step 3DP was used to process these filaments into enteric printlets incorporating up to 50% drug loading with two different infill percentages (20 and 100%). X-ray Micro Computed Tomography (Micro-CT) analysis revealed that printlets with 20% infill had cavities in the core compared to 100% infill, and that the density of the 50% drug loading printlets was higher than the equivalent formulations loaded with 5% drug. In biorelevant bicarbonate dissolution media, drug release from the printlets was dependent on the polymer composition, drug loading and the internal structure of the formulations. All HPMCAS-based printlets showed delayed drug release properties, and in the intestinal conditions, drug release was faster from the printlets prepared with polymers with a lower pH-threshold: HPMCAS LG > HPMCAS MG > HPMCAS HG. These results confirm that FDM 3D printing makes it possible not only to manufacture delayed release printlets without the need for an outer enteric coating, but it is also feasible to adapt the release profile in response to the personal characteristics of the patient, realizing the full potential of additive manufacturing in the development of personalised dose medicines., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This article describes a proof of concept study designed to evaluate the potential of an in vivo three-dimensional printing route to support minimally invasive repair of the musculoskeletal system. The study uses a photocurable material to additively manufacture in situ a model implant and demonstrates that this can be achieved effectively within a clinically relevant timescale. The approach has the potential to be applied with a wide range of light-curable materials and with development could be applied to create functionally gradient structures in vivo.

This article presents an overview on typical properties, technologies, and applications of liquid metal based flexible printed electronics. The core manufacturing material-room-temperature liquid metal, currently mainly represented by gallium and its alloys with the properties of excellent resistivity, enormous bendability, low adhesion, and large surface tension, was focused on in particular. In addition, a series of recently developed printing technologies spanning from personal electronic circuit printing (direct painting or writing, mechanical system printing, mask layer based printing, high-resolution nanoimprinting, etc.) to 3D room temperature liquid metal printing is comprehensively reviewed. Applications of these planar or three-dimensional printing technologies and the related liquid metal alloy inks in making flexible electronics, such as electronical components, health care sensors, and other functional devices were discussed. The significantly different adhesions of liquid metal inks on various substrates under different oxidation degrees, weakness of circuits, difficulty of fabricating high-accuracy devices, and low rate of good product-all of which are challenges faced by current liquid metal flexible printed electronics-are discussed. Prospects for liquid metal flexible printed electronics to develop ending user electronics and more extensive applications in the future are given.

Intestinal transplantation remains a life-saving option for patients with severe intestinal failure. With the advent of advanced tissue engineering techniques, great strides have been made toward manufacturing replacement tissues and organs, including the intestine, which aim to avoid transplant-related complications. The current paradigm is to seed a biocompatible support material (scaffold) with a desired cell population to generate viable replacement tissue. Although this technique has now been extended by the three-dimensional (3D) printing of geometrically complex scaffolds, the overall approach is hindered by relatively slow turnover and negative effects of residual scaffold material, which affects final clinical outcome. Methods recently developed for scaffold-free 3D bioprinting may overcome such obstacles and should allow for rapid manufacture and deployment of "bioprinted organs." Much work remains before 3D bioprinted tissues can enter clinical use. In this brief review we examine the present state and future perspectives of this nascent technology before full clinical implementation., (Copyright © 2016 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Articular repair is a relevant and challenging area for the emerging fields of tissue engineering and biofabrication. The need of significant gradients of properties, for the promotion of osteochondral repair, has led to the development of several families of composite biomaterials and scaffolds, using different effective approaches, although a perfect solution has not yet been found. In this study we present the design, modeling, rapid manufacturing and in vitro testing of a composite scaffold aimed at osteochondral repair. The presented composite scaffold stands out for having a functional gradient of density and stiffness in the bony phase, obtained in titanium by means of computer-aided design combined with additive manufacture using selective laser sintering. The chondral phase is obtained by sugar leaching, using a PDMS matrix and sugar as porogen, and is joined to the bony phase during the polymerization of PDMS, therefore avoiding the use of supporting adhesives or additional intermediate layers. The mechanical performance of the construct is biomimetic and the stiffness values of the bony and chondral phases can be tuned to the desired applications, by means of controlled modifications of different parameters. A human mesenchymal stem cell (h-MSC) conditioned medium (CM) is used for improving scaffold response. Cell culture results provide relevant information regarding the viability of the composite scaffolds used., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Plantar foot surface temperature has been identified as a clinically relevant physiological variable. Embedding sensors in foot orthoses (FOs) may allow long term monitoring of these temperatures, with compliance via the detection of periods of activity being a potential clinical utilization. This study aimed to test novel designs for FOs with embedded sensing that were produced via additive manufacturing and determine if foot temperature measurements could be used to detect periods of increased activity. FOs with embedded temperature sensors were developed and tested in 10 healthy participants over four day wear periods. Activity monitoring was used to estimate energy expenditure during testing. A threshold-based algorithm was developed to identify time periods of high activity from foot temperature data. Group differences in estimated energy expenditure between time periods below and above the threshold were significant in both the training and validation sets (p<0.001). Significant differences were also seen at individual participant level (p<0.001 in all cases). These results demonstrate the feasibility of using FOs with embedded sensing to monitor plantar surface foot temperatures during normal daily activities and for extended periods and show that periods of increased activity can be identified using foot temperature data., (Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.)