Zhang Qinlanhui, Ye Zheng, Wu Yange, Zhu Yufan, Liu Jiaqi, Yang Wenke, Ye Chengxinyue, Lau Rui Han Sophie, Wang Jun, Xiong Xin
State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, Department of Temporomandibular Joint, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
J Clin Med. 2022 Dec 1;11(23):7160. doi: 10.3390/jcm11237160.
Objective: to explore the association between the distance of disc displacement and disc morphology in patients with temporomandibular disorders (TMDs). Methods: a total of 717 joints in 473 subjects were enrolled in this cross-sectional study. The magnetic resonance imaging (MRI) of each patient was evaluated for temporomandibular joint (TMJ) disc morphology classification and position. The distance of the disc displacement and disc length were measured for smoothing spline prediction. A stratified analysis was performed based on the types of disc positions. The disc width and length-width ratio (L/W) were also measured. Descriptive statistics, one-way analysis of variance, smoothing spline analysis, threshold analysis, and two piecewise linear regression were performed to investigate the association between the displacement distance and length of discs. Results: the differences in displacement distance among morphological categories and among different disc positions were statistically significant. Nonlinear relationships were found between distance and length in all subjects. Two turning points of distance (−1.8 mm and 1.7 mm) were found, dividing the curve into three segments. Disc width and L/W were significantly different among discs in the three segments of the curve. The correlation coefficient (β) for the three segments were as follows: −0.6 [95% confidence interval (CI) = −0.9 to −0.3, p < 0.001], 0.0 (95% CI = −0.1 to 0.0, p = 0.027), and −0.7 (95% CI = −0.8 to −0.7, p < 0.001). Nonlinear relationships were also found between the distance and length in cases with anterior disc displacement (ADD), anterior disc displacement with reduction (ADDWR), and without reduction (ADDWoR). Conclusion: the turning points of the disc displacement distance may be considered as a potential reference value for high-risk disc deformation and ADD. Disc length decreases sharply with anterior disc displacement when the disc displacement distance is over 1.7 mm. Prospective and long-term studies are required to clarify the natural course of the disc at different stages of the regression curve.
探讨颞下颌关节紊乱病（TMDs）患者盘移位距离与盘形态之间的关联。方法：本横断面研究共纳入473名受试者的717个关节。对每位患者的磁共振成像（MRI）进行颞下颌关节（TMJ）盘形态分类及位置评估。测量盘移位距离和盘长度以进行样条平滑预测。根据盘位置类型进行分层分析。还测量了盘宽度及长宽比（L/W）。进行描述性统计、单因素方差分析、样条平滑分析、阈值分析及两段式线性回归，以研究盘移位距离与长度之间的关联。结果：形态类别之间以及不同盘位置之间的移位距离差异具有统计学意义。在所有受试者中发现距离与长度之间存在非线性关系。发现距离的两个转折点（-1.8mm和1.7mm），将曲线分为三段。曲线三段中的盘宽度及L/W存在显著差异。三段的相关系数（β）如下：-0.6[95%置信区间（CI）=-0.9至-0.3，p<0.001]，0.0（95%CI=-0.1至0.0，p=0.027），以及-0.7（95%CI=-0.8至-0.7，p<0.001）。在前盘移位（ADD）、可复性前盘移位（ADDWR）和不可复性前盘移位（ADDWoR）病例中，距离与长度之间也发现了非线性关系。结论：盘移位距离的转折点可被视为盘变形和ADD高风险的潜在参考值。当盘移位距离超过1.7mm时，随着前盘移位，盘长度急剧减小。需要进行前瞻性长期研究以阐明回归曲线不同阶段盘的自然病程。
