安氏Ⅱ类错关节窝、髁突、关节盘位置及关节盘形态变化的研究

The study on both fossa-condylar-meniscus positions and meniscus morphological change in patients with class Ⅱ malocclusion.

目的 :为探讨安氏Ⅱ1、Ⅱ2 错与颞下颌关节紊乱病之间的关系。方法 :利用矫正薛氏位X线片对Ⅱ1错16人 ,Ⅱ2 错 17人的双侧颞下颌关节的髁突居关节窝的位置进行评价 ,并依据髁突居关节窝中的位置 (前移、居中、后移 ) ,从上述两类错中各选 5人做双侧颞下颌关节矢状位核磁共振扫描 ,观察关节盘的位置及形态变化。结果 :每一类型错髁突居关节窝中的位置并不一致 :Ⅱ1错髁突居关节窝中位 ,但轻度前移 ;Ⅱ2 错髁突居关节窝后位。当髁突居前位及中位时 :关节盘位置在正常范围且形态表现为正常的双凹形 ;髁突居关节窝后位时 :部分关节盘位置明显前移 ,且形态也表现出异常的前带增厚。结论 :大多数Ⅱ1错颞下颌关节结构基本正常 ;而Ⅱ2错部分患者表现出颞下颌关节结构异常 。

Objective: To evaluate both fossa-condylar-meniscus positions and meniscus morphological change in patients with class Ⅱ division 1 and 2 malocclusion in order to find out which type of malocclusion was related to structural and functional disorder of TMJ and whether the variation of TMJ structure was similar at the same type of malocclusion. Method: 33 pretreatment orthodontic patients were examined on right and left TMJ with corrected lateral cephalometric radiograghs. Bilateral TMJ relationships of fossa-condyles were observed with subjective evaluation, linear and area measurement. 10 from 33 patients meniscus positions and morphological change were imaged with 0.5-T sagittal magnetic resonance imaging system on right and left TMJ. Results: ①The variation of condylar-fossa positions at the same type of malocclusion were very large, Class Ⅰ 1 patients demonstrated concentricly positioned condyles, but predisposed slightly anteriorly positioned condyles; Class Ⅱ 2 patients demonstrated more posteriorly positioned condyles. ②When condyles were in anterior or concentric positions: meniscus positions and morphology were normal and in concavoconcave shapes; when condyles were in posterior positions: the most of meniscus positions were in normal range or in slightly anterior range and their shapes were also concavoconcave, the rest were in significantly more anteriorly and their shapes were abnormal with thicken anterior band. Conclusions: Most Class Ⅱ 1 malocclusion demonstrated normal structure and function of TMJ, Classs Ⅱ 2 malocclusion was obvious associated with abnormal structure and function of TMJ. [