颞下颌关节盘前移位患者关节骨形态与矢状向关节盘位置的关系

目的　利用磁共振成像（MRI）技术和锥形束CT（CBCT）分析颞下颌关节盘前移位患者矢状向关节盘位置与关节骨形态的关系。方法　对97例患者的178个颞下颌关节（TMJ）进行回顾性分析，根据矢状向MRI上关节盘的位置分成4组，即对照组（关节盘无移位）、轻度组（关节盘轻度前移位）、中度组（关节盘中度前移位）和重度组（关节盘重度前移位）。然后利用Mimics 20软件基于CBCT数据进行TMJ的相关形态学参数测量，包括髁突线性尺寸（宽度、长度和高度）、髁突体积和表面积，关节窝的深度和长度，关节结节倾斜角，关节前、上、后间隙等，并对各组矢状髁突位置进行评估。使用方差分析、非参数检验和卡方检验等比较关节形态及位置参数的组间差异，采用相关性分析探索矢状关节盘位置与关节测量参数之间的相关性。结果　髁突的线性尺寸、关节窝深度、关节倾斜角、关节间隙和矢状髁突位置分布在4组间差异有统计学意义，而关节窝长度在4组间差异没有统计学意义；相关性分析显示：髁突的线性尺寸、髁突的体积及表面积、关节窝的深度、关节结节倾斜角和关节上间隙与关节盘矢状位置之间存在显著负相关，而关节后间隙与矢状关节盘位置之间存在显著正相关。结论　TMJ骨形态与不同矢状关节盘位置之间存在相关性，应警惕临床看到的关节骨形态的退行性改变可能是患者存在关节盘前移位的标志。     

儿童功能性单侧后牙反患者的髁突对称性及矫治后髁突位置变化的研究

目的探讨儿童功能性单侧后牙反患者的髁突对称性及上颌扩弓治疗后髁突位置的变化。方法选择22例通过上颌扩弓成功矫治的功能性单侧后牙反儿童患者,男10例,女12例,年龄6.0-8.5岁,平均7.5岁作为实验组。另选择22例正常患者,男11例,女11例,年龄6.5-9.0岁,平均7.5岁作为对照组。反组矫治前后与对照组患者均拍摄曲面断层片和双侧闭口位矫正薛氏位片,测量髁突形态的不对称指数和髁突在关节窝中的相对位置。用SPSS 12.0软件进行统计分析。结果反组患者两侧髁突形态无明显不对称,与对照组相比,髁突高度(CH)、升支高度(RH)以及两者之和(CH+RH)的不对称指数均无统计学差异。反组矫治前(T1)两侧髁突在关节窝中的位置有明显差异,非反侧关节前间隙减小(P<0.05),上后间隙增大(P<0.05)。非反侧髁突在关节窝中的位置(R)相对反侧更加靠前(P<0.01)。矫治后(T2)双侧髁突位置变得相对对称。结论儿童功能性单侧后牙反患者的髁突形态相对对称,而髁突位置存在不对称性,说明下颌向反侧发生功能性偏斜,而这种偏斜并未导致髁突发生骨性不对称;正畸治疗可使两侧髁突位置更加协调。     

上颌四眼簧扩弓纠正早期功能性下颌偏斜的髁突位置变化研究

目的:通过颞下颌关节断层片测量,探讨上颌四眼簧扩弓纠正单侧后牙反(牙合),改善早期功能性下颌偏斜后髁突位置的变化.方法:混合牙列或早期恒牙列,单侧后牙反(牙合)伴有或不伴有前牙反(牙合),下颌功能性偏斜患者16例,采用上颌Quad-Helix扩弓法,对矫治前后颞下颌关节断层片进行测量分析.结果:单侧后牙反(牙合)矫正后,偏斜侧T1期与T2期髁突位置变化无统计学意义(P＞0.05).对侧髁突向后移动,即治疗后,对侧关节腔前间隙增大,上间隙和后间隙比治疗前减小(p＜0.05).结论:混合牙列或早期恒牙列,上颌四眼簧扩弓器纠正单侧后牙反(牙合),使髁突与关节窝关系发生改变,两侧髁突运动逐渐对称.     

Condyle fossa relationship associated with functional posterior crossbite,before and after rapid maxillary expansion

Objective:To investigate condylar symmetry and condyle fossa relationships in subjects with functional posterior crossbite comparing findings before and after rapid maxillary expansion (RME) treatment through low-dose computed tomography (CT).Materials and Methods:Twenty-six patients (14 girls and 12 boys, mean age 9.6 ± 1.4 years) with functional posterior crossbite (FPXB) diagnosis underwent rapid palatal expansion with a Hyrax appliance. Patients'' temporomandibular joints (TMJ) underwent multislice CT scans before rapid palatal expansion (T0) and after (T1). Joint spaces were compared with those of a control sample of 13 subjects (7 girls and 5 boys, mean age 11 ± 0.6 years).Results:Anterior space (AS), superior space (SS), and posterior space (PS) joint space measurements at T0 between the FPXB side and contralateral side demonstrated no statistically significant differences. After RME treatment (T1), all three joint spaces increased on both the FPXB side and the non-crossbite side. However, differences were statistically significant only for the SS when comparing the two sides at T1. SS increased more than AS and PS in the non-crossbite condyle (0.28 mm) and FPXB condyle (0.37 mm), and PS increased only on the FPXB side (0.34 mm).Conclusions:There were no statistically significant differences in condyle position within the glenoid fossa between the FPXB and non-crossbite side before treatment. Increases in joint spaces were observed after treatment with RME on both sides. These changes were, however, of small amounts.     

Comparative study of the temporomandibular joint space in maximum intercuspation and canine edge-to-edge positions in deep bite and non-deep bite subjects

In order to study the relationship between morphological properties of the TMJ and the mathematically predicted force distribution in the TMJ, the geometric distribution of the joint space on top of the condylar surfaces was evaluated. Seven deep bite subjects and seven non-deep bite subjects were used, and the joint space in the maximum intercuspation and canine edge-to-edge positions was analysed in each group. Standardized images of the TMJ were taken with computed tomography (CT) using a mandible positioner. The comparative ratio of joint space (CRJS) between the maximum intercuspation and the canine edge-to-edge positions was calculated and summarized on the map of the mean morphological outline of the condyle. On the balancing-side condyle, the CRJS of small value was distributed mainly on the anterior edge of the condyle in the non-deep bite group, whereas, in the deep bite group, it was distributed on the centre of the condyle. On the working-side condyle, the small CRJS was distributed around the lateral pole of the condyle in the non-deep bite group, whereas, in the deep bite group, it was found around the posterior part of the condyle. The distribution pattern of CRJS on the upper surface of the condyle in the non-deep bite group was consistent with the results of previous studies on mathematical simulation of TMJ loading. From the results of this study, it was suggested that the distribution of mechanical loading on the TMJ in the eccentric mandibular position would be highly affected by the comparative ratio of joint space. As the comparative ratio of joint space would be highly affected by the condylar position, the analysis of the morphology of the TMJ in relation to mechanical joint loading, in a future investigation, should be carried out on specific mandibular positions in relation to the function of the TMJ to be studied.     

Movement of the lateral and medial poles of the working condyle during mastication in patients with unilateral posterior crossbite.

Patients with unilateral posterior crossbite often show reverse sequential jaw movement patterns on the frontal view during mastication on the crossbite side. Recent studies show that such patients are prone to suffer from temporomandibular joint (TMJ) disc displacement, particularly the lateral portion. The purpose of this study was to examine the movement of the lateral and medial poles of the working condyle during mastication in such patients. Subjects were 12 consecutive patients with unilateral posterior crossbites and without TMJ disc displacements and 12 normal subjects. An optoelectronic jaw-tracking system with 6 degrees of freedom was used to record the motion of the lateral and medial poles of the working condyle during mastication of standardized hard, gummy jelly. The data from the first 10 cycles were analyzed. The lateral and medial poles of the condyle on the crossbite side moved more in the medial direction and less in the lateral direction during mastication in the crossbite patients than the condyle in the normal subjects. The lateral pole of the working condyle moved more in the posterior and inferior directions and less in the anterior direction than the medial pole in all subjects. These results suggest that these condylar movements in patients with unilateral posterior crossbites might be related to the susceptibility to TMJ disc displacement, particularly the lateral portion.     

基于锥形束CT分析骨性Ⅲ类高角伴下颌偏斜患者髁突形态和位置的研究

目的 应用锥形束CT（CBCT）对比分析骨性Ⅲ类高角伴下颌偏斜患者与个别正常牙合患者髁突的形态和位置。方法 选取2017年9月至2019年9月于上海交通大学医学院附属第九人民医院口腔正畸科就诊的患者40例，其中骨性Ⅲ类高角伴下颌偏斜患者20例（偏斜组），个别正常牙合患者20例（对照组）。所有患者于治疗前拍摄CBCT，使用Invivo 5.0软件对CBCT影像进行三维重建及测量，并比较两组患者两侧髁突形态和位置的差异。结果 （1）偏斜组患者两侧髁突形态和位置指标测量值比较发现，在髁突形态方面，偏斜侧髁突最大轴面面积、髁突高度、髁顶高度均比非偏斜侧小，差异均有统计学意义（均P < 0.05）。在髁突位置方面，偏斜侧髁突外间隙、上间隙和后间隙比非偏斜侧小；偏斜侧髁突前间隙、内间隙及髁突外突距比非偏斜侧大，差异均有统计学意义（均P < 0.05）。（2）对照组两侧髁突形态和位置指标测量值比较，差异均无统计学意义（均P > 0.05）。（3）偏斜组两侧髁突形态和位置指标测量值分别与对照组比较发现，在髁突形态方面，偏斜组偏斜侧髁突高度比对照组大，最大轴面面积比对照组小；非偏斜侧髁突高度大于对照组，差异均有统计学意义（均P < 0.05）。在髁突位置方面，偏斜组偏斜侧髁突上间隙小于对照组，髁突内间隙、前间隙、髁突外突距及髁突与正中矢状面距大于对照组，差异均有统计学意义（均P < 0.05）。结论 骨性Ⅲ类高角伴下颌偏斜患者双侧髁突的形态和位置具有明显的不对称性，偏斜侧髁突形态较对侧小，并向后上外方向移位。骨性Ⅲ类高角伴下颌偏斜患者的髁突高度比个别正常牙合患者大。     

A comparative assessment of mandibular condylar position in patients with anterior disc displacement of the temporomandibular joint.

PURPOSE: The purpose of this study was to determine whether the position of the mandibular condyle in patients with anterior disc displacement (ADD) is different from that of a control group with normal joints using a novel method to quantify the irregular shape of the temporomandibular joint (TMJ). MATERIALS AND METHODS: Twenty-six magnetic resonance images of TMJs with ADD were evaluated and compared with 14 normal joints. The position of the condyle was determined by using 2 different methods: 1) measuring the horizontal and vertical normalized distances in millimeters between the geometric centers of the glenoid fossa and the condyle and 2) calculating the anteroposterior joint space ratio. RESULTS: Using the first method, the horizontal distance between the centers of the condyle and the glenoid fossa was 14.0 +/- 11.1 in the ADD group and 5.3 +/- 10.9 in the control group (P <.001). The vertical distance was 64.7 +/- 22.7 in the ADD group and 68.3 +/- 32.9 in the control group (P =.015). The ratio of the horizontal and the vertical condylar displacement in the ADD group was 2.4. Using the second method, the anteroposterior joint space ratios in the ADD group and in the control group were 1.7 +/- 0.5 and 1.2 +/- 0.4, respectively (P =.001). CONCLUSION: This study found that condyles of patients with ADD were situated more posterior and superior in the fossa than those in the control group. Moreover, in the ADD group, the posterior condylar displacement was noted to be 2.4 times greater than the superior condylar displacement.     

上、下颌联合手术对髁突位置及其颞颌关节功能的影响

本文通过对16例上颌Le Fort Ⅰ型截骨,下颌体部截骨后,颞颌关节X光照片的测量,分析了髁状突的位置变化及其对颞颌关节功能的影响。结果发现在上颌前移下颌体部截骨后退后髁状突的位置移动较小,除个别病例外一般不伴有术后髁状突位置的移动及颞颌关节功能的改变.     

Temporomandibular joint articulations on working side during chewing in adult females with cross‐bite and mandibular asymmetry

Influence of mandibular asymmetry and cross‐bite on temporomandibular joint (TMJ) articulation remained unknown. This study aimed to investigate whether/how the working‐side condylar movement irregularity and articular spaces during chewing differ between patients with mandibular asymmetry/cross‐bite and control subjects. The cross‐bite group and the control group consisted of 10 adult female patients and 10 adult female subjects, respectively. They performed unilateral gum‐chewing. The mandibular movements were recorded using a video‐based opto‐electronic system. The 3D articular surface of the TMJ for each individual was reconstructed using CT/MRI data. For local condylar points, the normalised jerk cost (NJC) towards normal direction to the condylar surface, the angle between tangential velocity vector and condylar long axis and intra‐articular space were measured. Three rotatory angles at centre of the condyle were also measured. During closing and intercuspation, (i) movements of posterior portion of the deviated side condyle showed significantly less smoothness as compared with those for the non‐deviated side and control subjects, (ii) the rotations of the condyle on the deviated side induced greater intra‐articular space at posterior and lateral portions. These findings suggest that chewing on the side of mandibular deviation/cross‐bite may cause irregular movement and enlarged intra‐articular space at posterior portion of the deviated side condyle.     

Associations between the articular eminence inclination and condylar bone changes, condylar movements, and condyle and fossa shapes

Objectives

The purpose of the present study was to determine the inclination and height of the articular eminence with respect to the condylar bone changes, condyle shape, fossa shape and condylar movements in patients with and without temporomandibular joint (TMJ) dysfunction using cone-beam computed tomography (CBCT).

Methods

The associations between the eminence inclination and the condylar bone changes, condylar movements, condylar shape and fossa shape were evaluated in patients with TMJ disorders and control patients without TMJ disorders. The measurements of the articular eminence inclination were established on central sagittal slices of the TMJ. The central coronal slices were used to determine the condyle and fossa shapes. The types of movements of the condyles were determined on open-mouth images, and mandibular hypermobility or hypomobility was noted for each joint.

Results

There were no significant differences in the eminence inclination and height with respect to the condylar bone changes and condylar movements in the TMJ disorder group. However, there was a significant association between the eminence inclination and the fossa shape in the TMJ disorder group and significant associations between the eminence inclination and both the condyle and fossa shapes in the control group. The articular eminence inclination was steeper in the control group than in the TMJ disorder group.

Conclusions

The eminence inclination was steeper in the control patients than in the patients with TMJ disorders, and was not correlated with the condylar bone changes or condylar movements.     

Ⅲ类固定磁力功能矫治器对颞下颌关节影响的MRI研究

【摘要】目的：研究Ⅲ类固定磁力功能矫治器矫治后颞下颌关节的改建情况。方法：选择15例矫治前经X线头影测量分析,诊断为功能性和骨性Ⅲ类错畸形的患者为研究对象,采用Ⅲ类固定磁力功能矫治器进行治疗,在治疗前后使用MRI评估颞下颌关节的变化。结果：治疗后：1.关节前间隙增大,后间隙减小,关节间隙指数减小,髁突在关节窝内的位置发生向后移位;2.盘髁角、前带盘髁角增大,关节盘在生理范围内前移位,关节盘前带位置的变化与后带位置的变化一致;3.髁突头角增大,髁突前屈;4.节窝后斜面角和关节窝角,差异不显著。结论：固定磁力功能矫治器治疗后生长期Ⅲ类错畸形患者的TMJ发生了适应性改变,固定磁力功能矫治器矫治后髁突向后移位,关节盘前移位,双板区厚度减小,髁突头前屈。     

术前正畸对颞下颌关节关节盘及髁突位置和形态的影响

目的 探讨术前正畸对颞下颌关节关节盘及髁突位置和形态的影响。方法 选择骨性错畸形患者30例,在颞下颌关节磁共振图像上进行测量。通过关节间隙测量,判定髁突位置;通过髁突头长度、宽度和高度测量,判定髁突形态;关节盘位置和形态由直接观察判定,采用SPSS 24.0软件包对所得数据进行统计学分析,比较骨性Ⅰ、Ⅱ和Ⅲ类畸形患者在术前正畸前、后关节盘及髁突位置和形态变化。结果 术前正畸前、后关节间隙和关节间隙指数,髁突头长度、宽度和高度、关节盘前移角及关节盘形态差异均无统计学意义（P>0.05）。结论 术前正畸治疗不会导致骨性错畸形患者关节盘及髁突位置和形态改变。     

单侧后牙锁患者前伸及后退髁突运动轨迹的研究

目的探讨单侧后牙锁者在下颌前伸、后退运动过程中髁突运动轨迹的特征及其与正常者之间的差异。方法选择单侧后牙锁患者24例和个别正常25例,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌前伸、后退运动时髁突的运动轨迹。结果实验组在下颌前伸、后退运动过程中髁突轨迹曲折、不流畅、重合性差,两侧髁突运动不对称、侧方位移增大;其锁侧在矢状方向和空间位移上以及髁突矢状面倾斜度小于非锁侧(P<0.05),锁侧髁突矢状面倾斜度较对照组小(P<0.05),在髁突位移5mm处水平面髁突倾斜度大于对照组(P<0.05)。结论单侧后牙锁者下颌前伸、后退运动时两侧髁突运动不对称,侧方位移增加。     

采用锥形束CT分析安氏Ⅱ类1分类错牙合患者Twin-block矫治前后颞下颌关节的变化

目的 运用锥形束CT（CBCT）分析安氏Ⅱ类1分类错牙合在Twin-block矫治前后颞下颌关节位置及形态结构在三维方向上的变化。方法 选取20例处于生长发育高峰前期或高峰期的安氏Ⅱ类1分类错牙合患者,拍摄其功能矫治前后双侧颞下颌关节的CBCT片,运用InVivoDental软件对CBCT片进行三维重建并测量线距和角度,对测量结果进行统计学分析。结果 与治疗前相比,治疗后矢状向关节前间隙减小,关节上间隙和后间隙增大,冠状向关节上间隙增大（P<0.01）;髁突高度、矢状向髁突角度、横断面髁突前后径增加（P<0.01）。结论 采用Twin-block矫治器治疗安氏Ⅱ类1分类错牙合患者后,髁突在关节窝的位置和髁突部分骨性结构发生了一定程度的改变,髁突有新骨沉积,高度增加,在关节窝内的位置更向下和向前。CBCT的应用使颞下颌关节结构的变化得以量化,能对正畸治疗效果进行客观评价。     

He夹板治疗作用的生物力学评价

目的 分析Ｈｅ夹板对髁突在关节窝位置及受力状况的影响，探讨Ｈｅ夹板的生物力学的治疗机制。方法 采用ＣＴ扫描、Ａｕｔｏ－ＣＡＤ技术、计算机图像分析方法及有限元法对颞下颌关节紊乱病患者民未戴Ｈｅ夹板时颞下颌关节髁突位置及其应力分布特征进行对比。结果 戴Ｈｅ夹板后颞下面关节前间隙变窄，上、后间隙变宽，髁突向前下称位；髁突应务明显降低，主要表现在功能承载区前斜面及外侧；双侧髁突应力对称性有所改善。结论 改     

生长发育高峰前期与高峰期安氏Ⅲ类错(牙合)颞下颌关节CBCT比较分析

目的 应用锥形束CT(CBCT)分析安氏Ⅲ类错(牙合)不同CVM分期颞下颌关节(TMJ)的生长发育差异.方法 分别对60名恒牙早期均角安氏Ⅲ类患者和60名恒牙早期正常(牙合)在牙尖交错位进行CBCT扫描,按颈椎CVM分期进行分组,使用Invivo5软件对影像重建并进行数据测量.通过SPSS22.0软件采用LSD法分析比较生长发育高峰前期与高峰期的髁突生长发育差异.结果 安氏Ⅲ类错(牙合)组相比正常(牙合)组中髁突绝大多数位于关节凹前位.安氏Ⅲ类错(牙合)组CS3-CS4期与CS1-CS2期生长变化差值显示髁突上间隙、前间隙减小量、后间隙增长量与正常(牙合)组相比有统计学差异(P<0.05);髁突前后径减小量、髁突高度增长量与正常(牙合)组相比有统计学差异(P<0.05);关节窝深度、关节后斜面角减小量、关节窝前后径增长量与正常(牙合)组相比有统计学差异(P<0.05).结论 安氏Ⅲ类错(牙合)生长发育高峰期相对于高峰前期髁突绝大多数位于关节凹前位且在关节凹中的位置更靠前上.髁突垂直向发育过度,更为细长,关节凹浅而宽.     

颞下颌关节盘前移位关节间隙改变的X线研究

目的测量颞下颌关节盘前移位患者与健康成人许勒位片上的关节间隙,分析髁突在关节窝中的位置,探讨髁突后移位在关节盘前移位临床诊断中的价值。方法选择120例（120侧）关节盘前移位患者和30例健康成人,拍摄许勒位片,使用AutoCAD计算机软件,采用2种线距测量方法（张震康法和Kamelchuk法）在许勒位片上测量关节间隙,并计算ln（P/A）值,比较关节盘前移位患者与健康成人（对照组）关节间隙的差异。结果2种测量方法的测量结果均显示：关节盘前移位组的关节上间隙和后间隙均小于对照组,其差异有统计学意义（P<0.05）,而关节前间隙与对照组的差异无统计学意义（P>0.05）;关节盘前移位组ln（P/A）值均小于对照组相应ln（P/A）值,其差异有统计学意义（P<0.05）。结论许勒位片上显示的颞下颌关节髁突后移位在一定程度上提示有关节盘前移位的存在;但正常髁突位置也存在变异,单纯的许勒位片尚不能作为关节盘前移位的确切诊断依据。     

Evaluation of condylar position from temporomandibular joint radiographs

This investigation evaluated the accuracy of three different transcranial TMJ radiographic records of condylar position and joint space dimension. In addition, the study evaluated how reliably observers determined condylar position and joint space dimensions from the radiographs. The results of this investigation support the following conclusions. The classification of condylar position is not the same at different sagittal locations within a TMJ. Skull position and radiographic projection must be identical if joint space measurements from serial radiographs are to be compared. The actual joint space dimensions and the anatomic anterior/posterior position of the condyles in the glenoid fossae cannot be accurately recorded by the radiographic techniques used in this investigation. Condyle/fossa relationships cannot be classified reliably by subjective evaluation of TMJ radiographs.     

A magnetic resonance imaging study on the temporomandibular joint disc–condyle relationship in young asymptomatic adults

The aim of this study was to assess the temporomandibular joint (TMJ) disc–condyle relationship in asymptomatic young adults. Ninety-three volunteers aged 19–23 years without temporomandibular disorder (TMD) symptoms underwent TMJ magnetic resonance imaging (MRI). The condylar centre and apex methods were used to measure and analyse the position of the disc in the oblique sagittal plane, and the reliability of the two methods was compared by calculating the intra-class correlation coefficient (ICC). Furthermore, 18 of the volunteers were randomly selected for three-dimensional (3D) reconstruction of the TMJ structure and the disc–condyle relationship. The 3D TMJ structure was established by semi-automatic segmentation of the condyle and articular disc in ITK-SNAP software; the condylar apex method was then performed. It was found that only 33.3% of the posterior edge of the articular discs were located in the normal 12 o’clock position with respect to the condyle. Moreover, this study suggests that the condylar centre method lacks accuracy when compared to the condylar apex method in regard to the measurement of the TMJ disc–condyle relationship (0 < ICC_cen < ICC_apex < 1). The position of the articular disc (left and right) was more forward in young women when compared to young men. However, there was no significant difference in the TMJ disc–condyle position between the left and right sides in the same individual, although the two joint discs in the same individual were not completely symmetrical.