Wang Meiqing, Cao Hongtao, Ge Yali, Widmalm Sven E
Department of Oral Anatomy and Physiology and TMD, School of Stomatology, Fourth Military Medical University, Xi'an, China.
J Prosthet Dent. 2009 Aug;102(2):89-93. doi: 10.1016/S0022-3913(09)60116-5.
Studies of temporomandibular joint (TMJ) discs removed from autopsy specimens and in surgery indicate that they are often thicker in patients with temporomandibular disorders (TMDs). Disc thickness may also change when the condyle moves in and out of the joint fossa during opening and closing.
The purpose of this pilot study was to test the hypothesis that the TMJ disc thickness is greater in TMD patients than in healthy subjects and is affected by the degree of jaw opening.
Magnetic resonance images (MRI) were made of the TMJs in young volunteers, 9 asymptomatic subjects and 9 TMD subjects, at closed and at 10-, 20-, and 30-mm open positions. The thickness of the anterior and posterior bands of the discs and the intermediate zones was measured and compared between TMD and control groups, and between closed and opened positions, using the repeated-measures method in general linear model (alpha=.05).
The hypothesis that the disc was thicker in the TMD than in the control group was supported with respect to the anterior band and intermediate zone (P<.046), but not with respect to the posterior band. The hypothesis that the thickness is affected by the degree of jaw opening was only supported for the posterior band, where it increased during opening in both groups (P<.005).
The results indicate that the anterior band and the intermediate zone of the TMJ discs are thicker in TMD patients than in healthy subjects. The posterior band thickness increases with mouth opening in both asymptomatic and TMD subjects.
对从尸检标本和手术中取出的颞下颌关节（TMJ）盘的研究表明，颞下颌关节紊乱病（TMD）患者的关节盘通常更厚。在开口和闭口过程中，当髁突进出关节窝时，关节盘厚度也可能发生变化。
本初步研究的目的是检验以下假设：TMD患者的TMJ盘厚度大于健康受试者，且受张口程度影响。
对9名无症状受试者和9名TMD受试者等年轻志愿者的TMJ进行磁共振成像（MRI），成像位置包括闭口位以及张口10毫米、20毫米和30毫米位。采用一般线性模型中的重复测量法（α = .05），测量并比较TMD组和对照组之间以及闭口位和开口位之间关节盘前后带及中间区的厚度。
TMD组关节盘前带和中间区比对照组厚这一假设得到支持（P < .046），但后带并非如此。厚度受张口程度影响这一假设仅在后带得到支持，两组在开口过程中后带厚度均增加（P < .005）。
结果表明，TMD患者TMJ盘的前带和中间区比健康受试者厚。无症状受试者和TMD受试者的后带厚度均随张口增加。
