ABSTRACT
Objective:To investigate the characteristics of gait festination in patients with Parkinson's disease. Methods:From January, 2016 to January, 2018, 20 Parkinson's disease patients with festination (festination group), other 20 Parkinson's disease patients without festination (non-festination group) (all in ON stage) and 20 healthy controls were tested BTS Motion Capture System and analyzed with SmartAnalyzer. Results:The stride time, swing time of left side and maximum ankle dorsiflexion angle of left side decreased in the festination group compared with those in the non-festination group, while the first peak of ankle appeared earlier (P < 0.05). The stance phase increased in the festination group compared with those in the controls (P < 0.05), while the swing phase, stride length, step length and velocity decreased, as well as the maximum ankle plantar flexion (P < 0.05), and the first peak of ankle appeared earlier (P < 0.05). Conclusion:Festination is characterized as less step length, faster step cadence and slower velocity. The first peak of ankle appeared earlier for the center of mass moving foreward. The maximum plantar flexion angle of the ankle reduces for the poor balance function.
ABSTRACT
<p><b>BACKGROUND</b>As the only active component in final treatment phase of Tip-Edge Plus technique, the activation of nickel-titanium orthodontic archwires is one of the factors that affect the torque expression. It is necessary to evaluate the mechanical properties of the nickel-titanium wire used in the final treatment phase in simulated oral environments to forecast the treatment outcomes.</p><p><b>METHODS</b>The mechanical properties of 171 thermal nickel-titanium wires of 0.35 mm (0.014-in) in diameters with different deflection of 40 mm in length were investigated with three-point bending test. The samples were divided into 2 groups: as-received and bended groups. In the bended group, samples were divided into 7 subgroups according to the amounts of deflection and named by the canine angulations (-25°, -19°, -13°, -7°, -1°, +5°, +11°). The deflection of wires was made by inserting the wires into the deep tunnel of Tip-Edge Plus brackets positioned in plaster casts with different canine angulations to mimic the use of nickel-titanium wires in the final treatment phase. Immersed the bended group in artificial saliva (pH 6.8) and preserved at 37.0°C. Eight durations of incubation were tested: 1 to 8 weeks. Three analogous samples of each group and subgroups were tested per week. Stiffness (YS:E) and the load-deflection characteristics of unloading plateau section were obtained.</p><p><b>RESULTS</b>Significant changes in specific mechanical properties were observed in long-term immersed and large deflected wires compared with as-received groups. Both immersion time and deflection affected the mechanical properties of wires in the simulated oral environment, and the two factors had synergistic effect. In groups -25°, -19° and -13°, stiffness (YS:E) increased then decreased and average plateau force and ratio of variance decreased then increased correspondingly at specific time.</p><p><b>CONCLUSIONS</b>In the final treatment phase of Tip-Edge Plus technique, the mechanical properties of nickel-titanium wire are associated with the using time and amounts of deflection and it may affect treatment outcomes. As the main reason for wire deflection, canine crown angulation plays an important role in the wire performance. It may be wise to focus on the canine crown angulations and using time in clinic with Tip-Edge Plus technique and make proper adjustment to help to make sure the treatment outcomes.</p>