颞下颌关节盘移位自然转归的MRI评价

目的:借助磁共振技术,对未经治疗的颞下颌关节盘前移位患者的盘-髁距离、关节盘长度及髁突高度的变化进行定量测量分析,从而为制订治疗计划提供参考。方法:收集62例(83侧关节)在随访期间未经有创或不可逆治疗的颞下颌关节盘移位患者,在初诊及随访结束时拍摄MRI,分别对盘-髁距离、关节盘长度及髁突高度进行测量,采用SPSS13.0软件包对源数据进行t检验。结果:患者初次就诊时,平均年龄为30.4岁,平均随访时间10.9个月。初诊时,39侧关节为可复性关节盘前移位,其中27侧随访期结束时变为不可复性关节盘前移位。随访结束时,盘-髁平均距离从初诊时的5.28mm增加至6.73mm,而关节盘的平均长度从8.31mm缩短至6.91mm,髁突高度从5.21mm降为4.65mm,以上变化均存在统计学差异(P<0.01)。结论:在颞下颌关节盘前移位的自然转归过程中,关节盘前移距离逐渐增大,关节盘长度逐渐缩短,髁突高度逐渐下降,但需更长期的随访及分层研究。

Changes in disc position,disc length,and condylar height in temporomandibular joint with anterior disc displacement:A longitudinal retrospective magnetic resonance imaging study

PURPOSE: The study is to quantitatively assess the changes in disc position relative to the condyle,disc length,and condylar height with magnetic resonance imaging of the temporomandivular joint disc displacement to provide useful information regarding treatment planning.METHODS: Sixty-two patients with 83 joints were involved and MRI scans of the temporomandibular joint were taken at initial and follow-up visits.The disc position relative to the condyle,disc length,and condylar height of the joints were assessed quantitatively on the MRI imagings.Student’s t test was used to assess the statistical significance of the changes with SPSS13.0 software package.RESULTS: The mean age of the patients at first visit was 30.4 years.The mean follow-up interval was 10.9 months.27 among the 39 joints with disc displacement with reduction at the initial visit changed to disc displacement without reduction after follow-up.The mean disc position relative to the condyle changed from 5.28 to 6.73 mm,whereas the mean disc length changed from 8.31 to 6.91 mm and the mean condylar height from 5.21 to 4.65 mm.Differences were all statistically significant(P<0.01).CONCLUSIONS: During the natural course of disc displacement,the disc would become more anteriorly displaced and shortened and the condylar height would decrease.However,further studies with longer follow-up and larger number of patients are necessary.