Department of Orthodontics, School of Dentistry & Dental Research Institute, Seoul National University, Seoul, Korea.
Angle Orthod. 2011 Jul;81(4):624-31. doi: 10.2319/091210-532.1. Epub 2011 Feb 7.
To investigate the relationship between temporomandibular joint disk displacement (TMJ DD) and facial asymmetry in skeletal Class III patients.
The subjects comprised 97 skeletal Class III adult patients seeking orthodontic treatment. In addition to the routine lateral and posteroanterior (PA) cephalograms, and regardless of the TMJ status, each subject consented to magnetic resonance imaging (MRI) to evaluate their TMJs. According to MRI readings, subjects were classified into four groups: group 1, bilateral normal disk position; group 2, bilateral DD with or without reduction; group 3, DD more advanced on the right side; and group 4, DD more advanced on the left side. PA and lateral cephalometric variables were analyzed to compare the four groups.
When the TMJ DD was more advanced on one side than on the other, the chin point usually deviated to the advanced side. When the TMJ DD status was equal or bilaterally normal, the amount of mandibular deviation was not significant.
If a skeletal Class III patient has an asymmetric face, especially in the mandibular region, careful examination is necessary with regard to the status of the TMJ during orthodontic diagnosis and treatment planning.
探讨颞下颌关节盘移位（TMJ DD）与骨性 III 类患者面部不对称的关系。
本研究纳入 97 例寻求正畸治疗的成人骨性 III 类患者。除了常规的侧位和后前位（PA）头颅侧位片外，无论 TMJ 状况如何，每位患者均同意进行磁共振成像（MRI）检查以评估其 TMJ。根据 MRI 结果，患者被分为四组：第 1 组，双侧正常盘位置；第 2 组，双侧 DD 伴或不伴复位；第 3 组，右侧 DD 更进展；第 4 组，左侧 DD 更进展。分析 PA 和侧位头颅侧位片变量以比较四组。
当一侧 TMJ DD 比另一侧更进展时，颏点通常向进展侧偏斜。当 TMJ DD 状况相等或双侧正常时，下颌偏斜量不显著。
如果骨性 III 类患者的面部不对称，特别是下颌区域，在正畸诊断和治疗计划中，有必要仔细检查 TMJ 的状况。
