Comparison of Neurosensory Recovery of the Inferior Alveolar Nerve After Open and Closed Reduction for Mandibular Fractures: A Prospective Study.

INTRODUCTION: Traumatic mandibular fractures are the most common fractures of the facial region and are associated with loss of neurosensation in the inferior alveolar nerve (IAN). The present study aimed to compare IAN recovery after traumatic mandibular fractures between the open and closed reduction methods. MATERIALS AND METHODS: The study included 90 patients with traumatic mandibular fractures of the body, angle, and symphysis, divided into two groups of 45 patients: group 1 was treated with closed reduction and fixation with rich arch-bar fixation under local anesthesia, and group 2 was treated with open reduction and rigid internal fixation with 2-mm titanium mini plates and monocortical screws (6 mm), and the plate was fixed to the fractured bony fragments. All patients underwent neurosensory testing using the Zuniga and Essick algorithm at baseline (preoperative), one week after surgery (postoperative), at three months, and at six months of follow-up. RESULTS: No statistically significant differences were observed in IAN recovery between the groups. The most common site of fracture was the body (44% in group 1 and 56% in group 2). The maximum recovery was observed in the younger age group (25-30 years). At baseline, functional nerve recovery was observed in 40 cases (88%) in group 1 and 38 cases (84%) in group 2, and the difference was not statistically significant. Levels A and B tests were affected by surgical management and improved after three months. The total recovery in group 1 ranged from 60% to 80%, and that in group 2 ranged from 56% to 72%. CONCLUSION: Based on the findings of the current study, both methods are recommended for surgical management of traumatic mandibular fractures with IAN recovery in 60-80% of cases six months postoperatively.

Material-level countermeasures for securing microfluidic biochips.

Flow-based microfluidic biochips (FMBs) have been rapidly commercialized and deployed in recent years for biological computing, clinical diagnostics, and point-of-care-tests (POCTs). However, outsourcing FMBs makes them susceptible to material-level attacks by malicious actors for illegitimate monetary gain. The attacks involve deliberate material degradation of an FMB's polydimethylsiloxane (PDMS) components by either doping with reactive solvents or altering the PDMS curing ratio during fabrication. Such attacks are stealthy enough to evade detection and deteriorate the FMB's function. Furthermore, material-level attacks can become prevalent in attacks based on intellectual property (IP) theft, such as counterfeiting, overbuilding, etc., which involve unscrupulous third-party manufacturers. To address this problem, we present a dynamic material-level watermarking scheme for PDMS-based FMBs with microvalves using a perylene-labeled fluorescent dye. The dyed microvalves show a unique excimer intensity peak under 405 nm laser excitation. Moreover, when pneumatically actuated, the peak shows a predetermined downward shift in intensity as a function of mechanical strain. We validated this protection scheme experimentally using fluorescence microscopy, which showed a high correlation (R2 = 0.971) between the normalized excimer intensity change and the maximum principal strain of the actuated microvalves. To detect curing ratio-based attacks, we adapted machine learning (ML) models, which were trained on the force-displacement data obtained from a mechanical punch test method. Our ML models achieved more than 99% accuracy in detecting curing ratio anomalies. These countermeasures can be used to proactively safeguard FMBs against material-level attacks in the era of global pandemics and diagnostics based on POCTs.

Structural Attacks and Defenses for Flow-Based Microfluidic Biochips.

Flow-based microfluidic biochips (FMBs) have seen rapid commercialization and deployment in recent years for point-of-care and clinical diagnostics. However, the outsourcing of FMB design and manufacturing makes them susceptible to susceptible to malicious physical level and intellectual property (IP)-theft attacks. This work demonstrates the first structure-based (SB) attack on representative commercial FMBs. The SB attacks maliciously decrease the heights of the FMB reaction chambers to produce false-negative results. We validate this attack experimentally using fluorescence microscopy, which showed a high correlation ( R2 = 0.987) between chamber height and related fluorescence intensity of the DNA amplified by polymerase chain reaction. To detect SB attacks, we adopt two existing deep learning-based anomaly detection algorithms with  âˆ¼ 96% validation accuracy in recognizing such deliberately introduced microstructural anomalies. To safeguard FMBs against intellectual property (IP)-theft, we propose a novel device-level watermarking scheme for FMBs using intensity-height correlation. The countermeasures can be used to proactively safeguard FMBs against SB and IP-theft attacks in the era of global pandemics and personalized medicine.