Aidar Luís Antônio de Arruda, Dominguez Gladys Cristina, Abrahão Márcio, Yamashita Hélio K, Vigorito Julio W
Department of Orthodontics, Santa Cecaília, University, Santos, Brazil.
Am J Orthod Dentofacial Orthop. 2009 Sep;136(3):412-24. doi: 10.1016/j.ajodo.2007.12.027.
The objective of this prospective study was to evaluate changes in the position and morphology of the disc in the temporomandibular joint (TMJ) with magnetic resonance imaging (MRI).
The subjects were 32 consecutive adolescent patients with Class II Division 1 malocclusion treated with the Herbst appliance. The MRIs were obtained immediately before treatment (T1), 8 to 10 weeks after appliance placement (T2), and 12 months later (T3).
Qualitative evaluation of the MRIs showed that, in 42 (65.62%) of the 64 TMJs, the disc was positioned within normal limits at T1. Because of the advancements caused by the Herbst appliance, a tendency for disc retrusion was observed at T2, but at T3 the disc had returned to normal limits. In 22 TMJs (34.37%), the disc was displaced at T1, and no changes were observed at T3. In most subjects, comparison of the morphology of the disc at T1, T2, and, T3 showed no significant change.
Herbst therapy does not cause adverse effects on the morphology and position of the articular disc in the short term.
本前瞻性研究的目的是利用磁共振成像（MRI）评估颞下颌关节（TMJ）中盘的位置和形态变化。
研究对象为32例连续接受Herbst矫治器治疗的安氏II类1分类错颌青少年患者。在治疗前（T1）、矫治器放置8至10周后（T2）以及12个月后（T3）获取MRI图像。
MRI的定性评估显示，在64个TMJ中的42个（65.62%）中，盘在T1时位置正常。由于Herbst矫治器导致的前导，在T2时观察到盘后移的趋势，但在T3时盘已恢复到正常位置。在22个TMJ（34.37%）中,盘在T1时移位，在T3时未观察到变化。在大多数受试者中，T1、T2和T3时盘的形态比较无显著变化。
Herbst治疗在短期内不会对关节盘的形态和位置产生不利影响。
