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Purpose 3D printing techniques have been widely used for manufacturing complex parts for various dental applications. For achieving suitable mechanical strength, post-cure processing is necessary, where the relative time duration and temperature specification also needs to be defined. The purpose of this study/paper is to assess the effects of post curing conditions and mechanical properties of 3D printed clear dental aligners Design/methodology/approach Dental long-term clear resin material has been used for 3D printing of dental aligners using a Formlabs 3D printer for direct usage on patients. Post-curing conditions have been varied, all of which have been subjected to mechanical compression loading of 1,000 N to evaluate the curing effects on the mechanical strength of the aligners. Findings The experimental studies provide significant insight into both temperatures and time durations that could provide sufficient compressive mechanical strength to the 3D printed clear dental aligners. It was observed that uncured aligners deformed plastically with large deformations under the loading conditions, whereas aligners cured between 400°C–800°C for 15–20 min deformed elastically before fragmenting into pieces after safely sustaining higher compressive loads between 495 N and 666 N. The compressive modulus ratio for cured aligners ranged between 4.46 and 5.90 as compared to uncured aligners. For shorter cure time durations and lower temperature conditions, an appropriate elevated compressive strength was also achieved. Originality/value Based on initial assessments by dental surgeons, suitable customised clear aligners can be designed, printed and cured to the desired levels based on patient’s requirements. This could result in time, energy and unit production cost savings, which ultimately would help to alleviate the financial burden placed on both the health service and their patients.

Clear dental aligners are commonly manufactured using thermoplastic materials such as Duran and Durasoft. Using conventional thermoforming methods there are inherent disadvantages including time consumption and poor geometrical accuracies that often occur. The use of digital technologies and 3D printing techniques for producing dental aligners is often preferred where possible. Innovation in 3D printing has resulted in bio-compatible materials becoming more readily available, including Formlabs Dental LT Clear resin, which is a 3D printable and Class IIa bio-compatible material. In this paper, we investigate the difference between thermoplastic materials such as Scheu-Dental Duran and Durasoft and 3D printed Dental LT using Finite Element Analysis (FEA)/Finite Element Modelling (FEM) in a dental aligner case based on an analysis of von Mises stress distribution at molars, incisors and canines for a total of 33161 nodes using Finite Element Analysis (FEA). Maximum von Mises stress distribution at all of the sections under the action of non-linear compressive forces equivalent to human biting force (up to 600 N) were discovered to vary within a range of 0.2–7.7% for Dental LT resin. The Duran and Durasoft cases were comparable, thereby widening the scope for the use of Dental LT in various dentistry applications, including clear aligners.

This proof-of-concept study aimed to assess the ability of a mobile application and cloud analytics software solution to extract facial expression information from participant selfie videos. This is one component of a solution aimed at extracting possible health outcome measures based on expression, voice acoustics and speech sentiment from video diary data provided by patients. Forty healthy volunteers viewed 21 validated images from the International Affective Picture System database through a mobile app which simultaneously captured video footage of their face using the selfie camera. Images were intended to be associated with the following emotional responses: anger, disgust, sadness, contempt, fear, surprise and happiness. Both valence and arousal scores estimated from the video footage associated with each image were adequate predictors of the IAPS image scores (p

Background Parkinson’s disease is the second most common long-term chronic, progressive, neurodegenerative disease, affecting more than 10 million people worldwide. There has been a rising interest in wearable devices for evaluation of movement disorder diseases such as Parkinson’s disease due to the limitations in current clinic assessment methods such as Unified Parkinson’s Disease Rating Scale (UPDRS) and the Hoehn and Yahr (HY) scale. However, there are only a few commercial wearable devices available, which, in addition, have had very limited adoption and implementation. This inconsistency may be due to a lack of users’ perspectives in terms of device design and implementation. This study aims to identify the perspectives of healthcare professionals and patients linked to current assessment methods and to identify preferences, and requirements of wearable devices. Methods This was a qualitative study using semi-structured interviews followed by focus groups. Transcripts from sessions were analysed using an inductive thematic approach. Results It was noted that the well-known assessment process such as Unified Parkinson’s Disease Rating Scale (UPDRS) was not used routinely in clinics since it is time consuming, subjective, inaccurate, infrequent and dependent on patients’ memories. Participants suggested that objective assessment methods are needed to increase the chance of effective treatment. The participants’ perspectives were positive toward using wearable devices, particularly if they were involved in early design stages. Patients emphasized that the devices should be comfortable, but they did not have any concerns regarding device visibility or data privacy transmitted over the internet when it comes to their health. In terms of wearing a monitor, the preferable part of the body for all participants was the wrist. Healthcare professionals stated a need for an economical solution that is easy to interpret. Some design aspects identified by patients included clasps, material choice, and form factor. Conclusion The study concluded that current assessment methods are limited. Patients’ and healthcare professionals’ involvement in wearable devices design process has a pivotal role in terms of ultimate user acceptance. This includes the provision of additional functions to the wearable device, such as fall detection and medication reminders, which could be attractive features for patients.

Introduction The aim of this research was to compare compressive mechanical properties and geometric inaccuracies between conventionally manufactured thermoformed Duran clear dental aligners and 3D printed Dental Long Term (LT) resin-based clear aligners using 3D modeling and printing techniques. Methods Impressions of the patient's dentition were scanned and using 3D modeling software, dental models were designed and 3D printed. These printed models then underwent vacuum thermoforming to thermoform a clear Duran thermoplastic sheet of 0.75-mm thickness into clear dental aligners of the same thickness of 0.75 mm. For the same dental model, aligners were also designed and 3D printed to 0.75-mm thickness creating biocompatible clear dental aligners using Dental LT resin utilizing a Formlabs 3D printing machine for direct usage by the patients. Five observers calculated teeth height for both types of aligners for evaluation of geometric deviations. Both types of aligners were subjected to compression loading of 1000 N to evaluate their load vs displacement behavior. Results 3D printed cured clear dental aligners were found to be geometrically more accurate with an average relative difference in tooth height of 2.55% in comparison with thermoformed aligners (4.41%). Low standard deviations (0.03-0.09 mm) were observed for tooth height measurements taken by all the observers for both types of aligners. 3D printed aligners could resist a maximum load of nearly 662 N for a low displacement of 2.93 mm; whereas, thermoformed aligners could resist a load on only 105 N for 2.93-mm displacement. Thermoformed aligners deformed plastically and irreversibly for large displacements; whereas, 3D printed aligners deformed elastically with reversibility for lower displacements. Conclusions 3D printed and suitably cured Dental LT resin-based clear dental aligners are suggested to be more suitable for patient use as they are geometrically more accurate; this presents an opportunity to make processing time savings while ensuring an aligner is mechanically stronger and elastic in comparison with the conventionally produced thermoplastic-based thermoformed clear dental aligners.

Applications utilising 3D Camera technologies for the measurement of health outcomes in the health and wellness sector continues to expand. The Intel® RealSense™ is one of the leading 3D depth sensing cameras currently available on the market and aligns itself for use in many applications, including robotics, automation, and medical systems. One of the most prominent areas is the production of interactive solutions for rehabilitation which includes gait analysis and facial tracking. Advancements in depth camera technology has resulted in a noticeable increase in the integration of these technologies into portable platforms, suggesting significant future potential for pervasive in-clinic and field based health assessment solutions. This paper reviews the Intel RealSense technology’s technical capabilities and discusses its application to clinical research and includes examples where the Intel RealSense camera range has been used for the measurement of health outcomes. This review supports the use of the technology to develop robust, objective movement and mobility-based endpoints to enable accurate tracking of the effects of treatment interventions in clinical trials.

Background: This paper describes the development of a new airway device that will improve the speed and safety of endotracheal intubation in anaesthesia and critical care. Case of need, design specification and fabrication of the steerable bougie mechanism is discussed. Aims: Identify the need for a novel steerable bougie whilst considering technology readiness levels associated with medical device design. Analyse and produce suitable mechanisms utilising smart materials to increase device functionality aiding successful patient intubation procedures. Methods: This work describes the total design activity that contributes to the successful development of medical devices, from case of need, to smart material actuation mechanisms. Research focuses on identifying a suitable control mechanism to allow a steerable tip to be integrated into a bougie with a control device attached to the laryngoscope. Results: Data collected from a user group survey supported the development of a novel bougie, with better shape retention, variable rigidity within the tip, and an integrated steerable function. Analysis of several mechanisms, artificial muscles, and smart materials identified a cost-effective steerable mechanism that can be incorporated into a bougie. Conclusion: Users have defined a need for an improved bougie. Controlling smart materials and mechanisms, within the predefined dimensions, identified strengths and weaknesses associated with steerable functions. The performance of the selected mechanism for incorporation requires a high level of control to accurately steer a device within the human airway.