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Condylar displacement can lead to temporomandibular joint (TMJ) symptoms and relapse after orthognathic surgery. To minimize condylar displacement, numerous condylar positioning techniques have been applied in clinical practice. To verify the effectiveness of condylar positioning techniques in preventing postoperative TMJ symptoms and relapse, we reviewed the literature related to all types of intraoperative condylar positioning techniques in the past 20 years. According to a literature review, positioning techniques aim to seat the condyles at a preoperative position during surgery and are divided into noncomputer-aided and computer-aided condyle positioning methods. At present, computer-aided design/computer-aided manufacturing condylar positioning devices (CAD/CAM CPDs) are the most superior positioning methods and are composed of teeth-supported and bone-supported guidance. The sequence of the remaining technology positioning effect from high to low is as follows: CAD/CAM titanium plate positioning > manual positioning > computer-aided navigation system > image positioning system. Different techniques reach considerable accuracy within 1-2 mm and 1°-2° in locating the preoperative condylar position and preventing TMJ symptoms or disorders and surgical relapse to provide a clinical reference for different levels of surgeons and cases. However, this study lacks randomized controlled trials with large samples and long-term follow-up. Future studies should upgrade the current methods, improve the clinical utility, and develop new positioning techniques.

Liquid metal motors are unconventional transformable machines whose motion control is important for microfluidics, drug delivery, and small‐scale robots. Without an external field, aluminum‐fueled liquid metal motors can achieve autonomous propulsion, but the random direction limits their applications. Here, the study reports a fundamental discovery of directionally reversing such liquid metal motors through a rotating magnetic field tuning approach. Systematic experiments reveal that the motor overcomes irregular Brownian motion and the volume limitation of liquid metals in magnetic control. Depending on its volume, the motor exhibits three different responses: moving opposite to the rotating magnet for smaller volumes, spinning in place at medium sizes, and moving with the magnet for larger ones. This phenomenon is attributed to the interaction of electromagnetic remote inductions, electrochemical reactions, and fluid dynamics. Rapidly changing magnetic fields induce currents and Ampere's force in the motor, restricting the locations of chemical reactions. Surface tension gradient and bubble recoil dominate the motion of small motors opposite to the magnet. As practical illustrations, this magnetically controlled motor displays advantages in rapid fluid mixing. Overall, the present finding significantly improves the controllability of liquid metal motors and would generate profound impacts on developing future small soft robots. [ABSTRACT FROM AUTHOR]

Objective To explore the clinical effect of simultaneous distraction osteogenesis of the maxilla and affected mandible combined with second-stage orthognathic surgery for the treatment of adult hemifacial microsomia to provide a reference for clinical practice.Methods Twelve adult patients with hemifacial microsomia who underwent simultaneous distraction osteogenesis and second-stage orthognathic surgery from 2006 to 2013 were enrolled. Distraction osteogenesis of the maxilla and malformed lateral mandible and second-stage orthognathic surgery were performed according to each patient’s specific conditions. The height ratio of the mandibular ramus of the affected side to the contralateral side, the shift distance of the chin point and the inclination angle of the screw plane were measured before and after the operation, and the therapeutic effect was evaluated with clinical photographs.Results No patients had obvious complications after the operation, the postoperative aesthetic effect was good, and the relationship between the facial shape and occlusion was significantly improved. The cephalometric measurement showed that the height ratio of the mandibular ramus of the affected side to the contralateral side was increased by 23.83% (t=11.658, P

Post-construction settlement in embankments is a crucial quality indicator and a significant factor influencing the long-term stability of roadbeds. Especially for the mixed-fill materials, by considering the uncertainty of composition and mechanical properties, it is important to predict and take construction measures to control post-construction settlement. In this paper, taking the construction of high-fill embankments with red bed soft rock mixture as the background, the deformation characteristics of mixed-fill materials were revealed first. Then, a dynamic–static coupling method for roadbed filling was proposed, and corresponding control parameters were provided. Finally, by employing ABAQUS 2016 for long-term settlement numerical simulations and conducting load-bearing preloading tests, the deformation patterns of the high embankment with red bed soft rock mixture fill roadbed were revealed. [ABSTRACT FROM AUTHOR]