São Paulo State University, School of Dentistry, Department of Morphology and Child Clinic - Orthodontics (Araraquara/SP, Brazil).
Dental Press J Orthod. 2024 Oct 4;29(5):e242430. doi: 10.1590/2177-6709.29.5.e242430.oar. eCollection 2024.
This study evaluated the force system generated by the Memory Titanol® spring (MTS) with different preactivation bends using an orthodontic force tester (OFT).
Three preactivations were tested using a 0.017 × 0.022-in stainless steel (SS) wire and a 0.018 × 0.025-in NiTi segment, with an activation of 30º in the posterior segment (β), with 0º (Group 1 [G1]), 45º (Group 2 [G2]), and 60º (Group 3 [G3]) in the anterior segment (α).
The molars showed extrusion values of -1.33 N for G1 and -0.78 N for G2, and an intrusion value of 0.33 N for G3. The force in the premolars was intrusive with a variation of 1.34 N for G1 and 0.77 N for G2; and extrusive with a variation of -0.31 N for G3. Regarding the upright moment (Ty) of the molar, a distal moment was observed with values of 53.45 N.mm for G1 and 19.87 N.mm for G2, while G3 presented a mesial moment of -6.23 N.mm. G1, G2, and G3 all exhibited distal premolar moments (Ty) of 3.58, 2.45, and 0.68 N.mm, respectively.
The tested preactivations exerted an extrusive force in G1 and G2 and an intrusive force in G3 during molar vertical movement. The premolar region in G1 and G2 showed intrusive force and distal moment.
本研究通过正畸力测试仪（OFT）评估不同预激活弯曲的 Memory Titanol® 弹簧（MTS）产生的力系统。
使用 0.017×0.022 英寸不锈钢（SS）丝和 0.018×0.025 英寸 NiTi 段测试了三种预激活，后段（β）的激活为 30°，前段（α）的预激活分别为 0°（G1 组）、45°（G2 组）和 60°（G3 组）。
磨牙的外展值分别为 G1 组的-1.33N 和 G2 组的-0.78N，G3 组的内收值为 0.33N。G1 组前磨牙的力为内收，变化值为 1.34N，G2 组的力为内收，变化值为 0.77N；G3 组的力为外展，变化值为-0.31N。关于磨牙的垂直向上矩（Ty），观察到 G1 组的远中矩为 53.45N·mm，G2 组的矩为 19.87N·mm，而 G3 组表现为近中矩-6.23N·mm。G1、G2 和 G3 组的近中磨牙矩（Ty）分别为 3.58、2.45 和 0.68N·mm。
在磨牙垂直运动中，测试的预激活在 G1 和 G2 中产生了外展力，在 G3 中产生了内收力。G1 和 G2 中的前磨牙区表现出内收力和远中矩。
