安氏Ⅲ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 skeletal anddental class Ⅲ malocclusion

目的为探讨骨性和功能性Ⅲ类错与颞下颌关节紊乱病之间的关系。方法利用矫正薛氏位片对Ⅲ类骨性错19人，功能性错20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，但位置分布比较集中，Ⅲ类骨性和功能性错髁突明星居关节窝前位，当髁突居前位或中位时，关节盘位置在正常范围且形态为正常的双凹形，髁突居后位时，关节盘位置在正常范围或轻度前移，形态也都表现正常。结论Ⅲ类骨性和功能性错颞下颌关节结构基本正常，与颞下颌关节紊乱病关系不密切。

Objective To evaluate both fossa - condylar - meniscus positions and meniscus morphological change in patients withskeletal and dental class Ⅲ malocclusion in order to find out whether these two types of malocclusion were related to internal derangements of TMJ and whetherthe variation of TMJ structure was similar at the same type of malocclusion. Methods 39 pretreatment orthodontic patients were examined on right and left TMJ with corrected lateral cephalometric radiographs. Bilateral TMJ relationship of fossa - condyles were observed with subjective evaluation, linear and areameasurement. 10 from 39 patients' meniscus positions and morphological change were imaged with 0. 5 - T sagittal magnetic resonance imaging system on right and left TMJ. Results 1. The variations of condylar - fossa positions at the sametype of malocclusion were not similar. 2. Skelctal and dental class Ⅲ paticnts demonstrated significantly more anteriorly positioned condyles. 3. Most of meniscus positions were in normal range, few of their positions were in slightly anterior rangeand all of the shapes were normal with concavoconcave. Conclusion The structure of TMJ with skeletal and dental classⅢ malocclusion was normal, so these malocclusion did not have any strong groups association to TMD.