下颌定位仪指导下颌稳定性(牙合)垫调磨对髁突运动中心位置的影响

目的：观察[牙合]垫对髁突运动中心位置的影响,并探讨下颌定位技术测定髁突运动中心电子位置（ele-ctronic position analysis,EPA）指导[牙合]垫调磨的方法。方法：从3158例颞下颌关节紊乱病患者中,选择46例（92侧关节）有下颌绞锁运动症状的颞下颌关节紊乱病患者,接受下颌稳定垫治疗;常规调磨后,为患者戴入合垫,再用超声三维下颌定位仪（3D-ultrasonic navigator）进行髁突运动中心电子位置及下颌运动功能分析,观察常规方法调磨后垫治疗对髁突运动中心的影响;对引起双侧髁突运动中心不均衡位移的病例,则根据EPA的测试,对[牙合]垫进行修正性调磨。结果：常规调磨后,67.4%（31/46）的患者双侧髁突运动中心在矢状位的位移距离明显不均衡;63%（29/46）的患者双侧髁突运动中心的位移方向不一致;而根据EPA检测修正性调磨后,91.3%（42/46）的患者双侧髁突运动中心的位移方向达到了一致。常规调磨与修正性调磨对[牙合]垫引起髁突运动中心位移时双侧的均衡性与方向一致性上的差异均具有统计学意义。结论：稳定[牙合]垫治疗颞下颌关节紊乱病过程中,超声三维下颌定位仪中的EPA检测指导下进行修正性调磨可以提高双侧髁突运动中心的位移距离和方向的一致性。     

下颌三维定位技术指导下稳定型殆垫治疗颞颌关节紊乱病的疗效分析

目的：探讨超声三维下颌定位技术指导下修正性调磨的骀垫对TMD的临床疗效。方法：本研究从北京口腔医院颞颌关节门诊2003年3月～2008年12月就诊的患者选用40例（男12例女28例）颞颌关节病并有关节绞锁的患者，超声三维下颌定位仪中的髁突运动中心电子位置分析（electronicpositionanalysis，EPA）检测指导下进行修正性调磨骀垫治疗后，比较治疗前后下颌运动程度如张口度、关节绞锁运动、弹响和下颌运动疼痛的变化情况。结果：本研究发现超声三维下颌定位技术指导下修正性调磨的殆垫治疗后，下颌运动明显改善，张口运动及被动最大张口度治疗前后均有显著性差异；绞锁运动症状明显改善。并有统计学差异。结论：超声三维下颌定位技术指导下修正性调磨的黯垫治疗TMD，能够改善TMD症状，在治疗绞锁运动方面有显著疗效。     

单侧后牙正锁(牙合)患者下颌侧方运动时的髁突轨迹特征

目的:探讨单侧后牙正锁(牙合)患者在下颌侧方运动过程中髁突的运动轨迹特征及其与正常(牙合)者之间的差异.方法:选取单侧后牙正锁(牙合)患者26例为实验组,个别正常(牙合)26例为对照组,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌侧方运动时髁突的运动轨迹.实验数据采用SPSS10.0软件包分析,选用成组t检验、配对t检验或秩和检验比较组间差异有无统计学意义.结果:实验组下颌侧方运动过程中髁突轨迹不流畅变异大,两侧运动轨迹不对称.非锁(牙合)侧髁突的矢状位移、垂直位移以及空间最大位移大于锁(牙合)侧和对照组,水平位移小于后者,差异有统计学意义(P<0.05);非锁(牙合)侧髁突的矢状倾斜度大于锁(牙合)侧和对照组,水平倾斜度小于后者,差异有统计学意义(P<0.05).结论:单侧后牙正锁(牙合)患者下颌侧方运动过程中两侧髁突运动轨迹不对称.     

暂时性绞锁颞下颌关节的运动特征研究

目的：本研究观察分析了暂时性绞锁颞下颌关节髁状突的运动轨迹特征。方法：对9名可复性盘前移位伴暂时性绞锁患以MT－1602下颌三维运动轨迹描记仪记录髁状突的运动数据,动态观察锁结和非锁结时的髁状突运动扫描轨迹。结果：发现锁结和非锁结时髁状突循两条不同路径滑动。结论：前移位关节盘后带在不同位置对髁状突阻力不一样,神经肌肉的功能状态在前移位关节盘的发展中不可忽视。     

下颌定位仪指导下颌稳定性垫调磨对髁突运动中心位置的影响

目的:观察垫对髁突运动中心位置的影响,并探讨下颌定位技术测定髁突运动中心电子位置(ele-ctronic position analysis,EPA)指导垫调磨的方法。方法:从3158例颞下颌关节紊乱病患者中,选择46例(92侧关节)有下颌绞锁运动症状的颞下颌关节紊乱病患者,接受下颌稳定垫治疗;常规调磨后,为患者戴入合垫,再用超声三维下颌定位仪(3D-ultrasonic navigator)进行髁突运动中心电子位置及下颌运动功能分析,观察常规方法调磨后垫治疗对髁突运动中心的影响;对引起双侧髁突运动中心不均衡位移的病例,则根据EPA的测试,对垫进行修正性调磨。结果:常规调磨后,67.4%(31/46)的患者双侧髁突运动中心在矢状位的位移距离明显不均衡;63%(29/46)的患者双侧髁突运动中心的位移方向不一致;而根据EPA检测修正性调磨后,91.3%(42/46)的患者双侧髁突运动中心的位移方向达到了一致。常规调磨与修正性调磨对垫引起髁突运动中心位移时双侧的均衡性与方向一致性上的差异均具有统计学意义。结论:稳定垫治疗颞下颌关节紊乱病过程中,超声三维下颌定位仪中的EPA检测指导下进行修正性调磨可以提高双侧髁突运动中心的位移距离和方向的一致性。     

下颌偏斜患者下颌侧方运动时髁突的运动轨迹特征

目的 通过记录下颌偏斜患者的髁突运动轨迹，研究此类患者髁突运动的规律。方法 下颌偏斜患者31例（男性9例，女性22例），年龄12～26岁，平均18岁。使用CADIAX　Ⅲ型髁突运动轨迹轴图描计仪，记录并通过配对t检验和秩和检验分析患者下颌侧方运动时髁突的运动轨迹，并将其与患者下颌偏斜量进行多元线性回归分析。结果下颌偏斜患者下颌侧方运动时髁突的运动轨迹不对称，偏斜侧的运动位移大于非偏斜侧，差异有统计学意义（P＜0．01）；偏斜侧髁突的水平倾斜度小于非偏斜侧，差异有统计意义（P＜0．01）。随着偏斜量的增加，偏斜侧与非偏斜侧髁突的位移差距也相应增加，非偏斜侧髁突的位移相应减小，差异有统计学意义（P＜0．05）。结论下颌偏斜患者不仅颅面形态不对称，下颌侧方运动时髁突运动轨迹在长度、角度等方面也不对称，其与偏斜量有一定的相关性。     

颞下颌关节疾病

小鼠听骨关节、镫骨前庭关节和下颌关节发育过程中的形态学观察；双侧下颌牵张成骨对转化生长因子β1在颞下颌关节髁突表达的影响；突发性严重绞锁颞下颌关节的压力测量和分析；稳定性（he）垫治疗颞下颌关节可复性盘前移位的疗效分析；5种不同张口位的颞下颌关节区三维有限元模型的建立；……[编者按]     

安氏Ⅱ1青少年髁突运动轨迹与颞下颌关节形态的研究

目的:探讨安氏Ⅱ1青少年髁突运动轨迹特征及相应的颞下颌关节形态特征.方法:选取青少年安氏Ⅱ1及直面型个别正常(牙合)各15例,应用髁突运动轨迹描记仪(CADIAX compact 2 )记录分析髁突运动轨迹特征,并且应用改良颞下颌关节闭口薛氏位X线片测量分析颞下颌关节形态特征.结果:下颌功能运动时,安氏Ⅱ1错(牙合)髁...     

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。     

髁突在关节窝中的位置及其在临床诊断治疗中的意义

临床治疗中,特别是髁突外伤骨折、正颌手术、修复咬合重建、正畸治疗以及在颞下颌关节紊乱病的诊断和治疗中,要考虑髁突在关节窝中的位置变化。本文通过文献回顾,结合我们的研究成果,讨论髁突在关节窝中的正常生理位置及其在颞下颌关节紊乱病特别是关节盘移位的诊断和治疗中的意义。目前多项研究认为,健康成年人髁突平均位置为基本中性,但存在较大变异;髁突后移可能是关节盘前移位的危险因素,关节盘前移位也可导致髁突后移;在关节盘移位的牙合垫治疗中,髁突在牙合垫戴入后显著向前、下移位,可有效改善盘突关系;稳定牙合垫使髁突前下移位不明显,改善盘突关系的效果有限。此外,再定位牙合垫使髁突前下移位还可促进髁突骨质的改建。     

3D evaluation of mandibular skeletal changes in juvenile arthritis patients treated with a distraction splint: A retrospective follow-up

Objective:To evaluate three-dimensional (3D) condylar and mandibular growth in patients with juvenile idiopathic arthritis (JIA) with unilateral temporomandibular joint involvement treated with a distraction splint.Materials and Methods:Cone-beam computed tomography (CBCT) scans were taken for 16 patients with JIA with unilateral TMJ involvement before treatment (T₀) and 2 years after treatment (T₁). All patients received orthopedic treatment with a distraction splint. Eleven patients without JIA who were undergoing orthodontic treatment without a functional appliance or Class II mechanics and who had taken CBCT scans before and after treatment, served as controls. Reconstructed 3D models of the mandibles at T₀ and T₁ were superimposed on stable structures. Intra- and intergroup growth differences in condylar and mandibular ramus modifications and growth vector direction of the mandibular ramus were evaluated.Results:In all patients with JIA there were asymmetric condylar volume, distal and vertical condylar displacement, and ramus length differences that were smaller on the affected side. Condylar displacement was more distal and less vertical in the JIA group than in the control group. A larger distal growth of the condylar head and a more medial rotation of the ramus on the affected side were found in the JIA group.Conclusion:The orthopedic functional treatment for patients with JIA allows for condylar adaptation and modeling, thereby hindering, although with a widely variable response, a further worsening of the asymmetry. Unilateral affection has a possible influence on the growth of the nonaffected side.     

Management of malunited mandibular condylar fractures

The non-surgical treatment of mandibular condylar fractures, may occasionally result in articular imbalance and temporomandibular joint dysfunction. This may be attributed to condylar head displacement and resorption, resulting in a shortened vertical ramus and lost posterior vertical facial height. Restoring the vertical ramus height is essential in the treatment of such dysfunction, and may be accomplished by unilateral, or bilateral ramus osteotomies. Four examples of patients treated with mandibular ramus osteotomies to restore vertical ramus height, with subsequent improvement in occlusal balance and function are presented. The use of the sagittal split mandibular osteotomy and the external vertical ramus osteotomy, stabilized with small osseous plates, and monocortical screws, is discussed.     

Evaluation of mandibular condylar movement exercise for patients with internal derangement of the temporomandibular joint on initial presentation

The aim of the present study was to evaluate mandibular condylar movement in a group of Japanese women who presented with closed lock of the temporomandibular joint. A total of 148 women aged between 19 and 75 years were included in the study. We examined mouth-opening, protrusion, and lateral excursive movements, and divided the patients into two groups (74 experimental cases and 74 controls). The experimental group was treated with exercises of the mandibular condyle, and the median (range) maximum mouth-opening increased from 27 (range 11-34) mm to 38 (24-47) mm. In control cases, it increased from 29 (range 20-35) mm to 30 (20-39) mm without exercise. In the experimental group, the median (range) maximum lateral movement on the opposite (unaffected) side increased from 8 (3-12) mm to 9 (5-13) mm. In the control group it remained similar at 7 (3-12) mm and 7 (3-12) mm. In the experimental group, the median (range) lateral movement on the affected side increased from 6 (2-13) mm to 8 (3-13) mm. In controls it remained similar at 6 (2-12) mm and 6 (2-12) mm. In the experimental group, the median (range) maximum protrusion increased from 6 (3-12) mm to 7 (4-12) mm, and in the control group from 6 (2-10) mm to 7 (2-10) mm. There was a significant difference between the experimental (50/74, 68%) and control groups (3/74, 4%) in the degree of increased mouth-opening. Exercise of the first mandibular condylar seems to be useful in the treatment of closed lock on initial treatment.     

Assessment of patients treated for intracapsular fractures of the mandibular condyle by closed techniques.

PURPOSE: The goals to study different lines of intracapsular fractures of the mandibular condyle and to evaluate their influence on the prognosis after closed treatment. PATIENTS AND METHODS: Clinical, radiologic, and axiographic follow-up of 40 patients with 50 intracapsular fractures of the mandibular condyle was carried out after closed treatment. The examinations were performed an average of 22 weeks after treatment. Three types of intracapsular fractures were distinguished: type A, or fractures through the medial condylar pole; type B, or fractures through the lateral condylar pole with loss of vertical height of mandibular ramus, and type M, multiple fragments, comminuted fractures. RESULTS: Moderate to serious dysfunction was observed in 33% of the cases. Radiologic examination of fracture types B and M revealed a reduction in the height of the mandibular ramus of up to 13% compared with the contralateral side. These 2 fracture types also resulted in the most prominent deformations of the condylar head. Axiography revealed irregular excursions and a limitation of condylar movement in comminuted fractures of up to 74% compared with the nonfractured side. CONCLUSION: Lesions to the osseodiscoligamentous complex of the temporomandibular joint caused by intracapsular fractures of the mandibular condyle can be severe. The poor functional and radiologic results encountered in the fracture types B and M showed the limitations of closed functional treatment.     

The functional shift of the mandible in unilateral posterior crossbite and the adaptation of the temporomandibular joints: a pilot study.

Changes in the functional shift of the mandibular midline and the condyles were studied during treatment of unilateral posterior crossbite in six children, aged 7-11 years. An expansion plate with covered occlusal surfaces was used as a reflex-releasing stabilizing splint during an initial diagnostic phase (I) in order to determine the structural (i.e. non-guided) position of the mandible. The same plate was used for expansion and retention (phase II), followed by a post-retention phase (III) without the appliance. Before and after each phase, the functional shift was determined kinesiographically and on transcranial radiographs by concurrent recordings with and without the splint. Transverse mandibular position was also recorded on cephalometric radiographs. Prior to phase I, the mandibular midline deviated more than 2 mm and, in occlusion (ICP), the condyles showed normally centred positions in the sagittal plane. With the splint, the condyle on the crossbite side was displaced 2.4 mm (P < 0.05) forwards compared with the ICP, while the position of the condyle on the non-crossbite side was unaltered. After phase III, the deviation of the midline had been eliminated. Sagittal condylar positions in the ICP still did not deviate from the normal, and the splint position was now obtained by symmetrical forward movement of both condyles (1.3 and 1.4 mm). These findings suggest that the TMJs adapted to displacements of the mandible by condylar growth or surface modelling of the fossa. The rest position remained directly caudal to the ICP during treatment. Thus, the splint position, rather than the rest position should be used to determine the therapeutic position of the mandible.     

Findings of mandibular movement and the position of the mandibular condyles during maximal mouth opening

An investigation with respect to position of the mandibular condyles in relation to maximal vertical mouth opening was undertaken. For this purpose, 51 subjects of different nationalities were examined. None of the 51 persons had a TMJ disorder. The mobility of the mandible in different directions was clinically measured. With the use of two different reference lines (Methods A and B), the amount of the movement of the condyle from closed to maximal mouth opening position was measured in the sagittal plane on lateral tomograms. All of the measurements were recorded, and the means, SD, and range of variation were calculated. Statistical analysis was subsequently performed. The clinical results are comparable to those of other previous clinical studies. As seen in the lateral tomograms, the condyle in 41 out of 51 subjects moved beyond the articular eminence during maximal mouth opening. It was occasionally situated higher than the eminence. In only ten subjects, the condyle reached only the top of the articular eminence during maximal mouth opening. A moderate degree of dependency and correlation was found between maximal vertical movement of the mandible and the amount of movement of the right and left condyles from closed to maximal open position of the mouth, as seen in tomograms. None of our subjects had any sign of luxation despite the position of the condyle beyond the articular eminence with maximal mouth opening. Therefore, the diagnosis of condylar luxation cannot be established by radiologic investigation alone.     

Evaluation of treatment with unilateral mandibular sagittal split ramus osteotomy and maxillary osteotomy in patients with condylar osteochondroma and mandibular asymmetry: A retrospective case series

The aim of the study was to describe an approach where condylar resection with condylar neck preservation was combined with Le Fort I osteotomy and unilateral mandibular sagittal split ramus osteotomy (SSRO).Patients with a unilateral condylar osteochondroma combined with dentofacial deformity and facial asymmetry who underwent surgery between January 2020 and December 2020 were enrolled. The operation included condylar resection, Le Fort I osteotomy and contralateral mandibular sagittal split ramus osteotomy (SSRO). Simplant Pro 11.04 software was used to reconstruct and measure the preoperative and postoperative craniomaxillofacial CT images. The deviation and rotation of the mandible, change in the occlusal plane, position of the “new condyle” and facial symmetry were compared and evaluated during follow-up. Three patients were included in the present study. The patients were followed up for 9.6 months on average (range, 8–12). Immediate postoperative CT images showed that the mandible deviation and rotation and occlusion plane canting decreased significantly postoperatively; facial symmetry was improved but still compromised. During the follow-up, the mandible gradually rotated to the affected side, the position of the “new condyle” moved further inside toward the fossa, and both the mandible rotation and facial symmetry were more significantly improved.Within the limitations of the study it seems that for some patients a combination of condylectomy with condylar neck preservation and unilateral mandibular SSRO can be effective in achieving facial symmetry.     

Clinical study on the relationship between chewing movements and temporomandibular joint abnormalities

Chewing movements are accomplished by the harmonious function of the stomatognathic system. Therefore, TMJs play important roles in chewing movements. Recently, significant findings on TMJ abnormalities have been obtained from many studies. However, the relationship between chewing movements and TMJ abnormalities remains unclear. The purpose of this study was to examine how TMJ abnormalities were reflected in chewing movements. Incisor point movements during chewing (chewing pattern) were investigated in 150 abnormal and 25 normal subjects using Sirognathograph Analysing System. Abnormal subjects were composed of 45 patients with anterior disk displacement with reduction (reciprocal click), 20 patients with anterior disk displacement without reduction (closed lock), 50 patients with osteoarthrosis and 35 patients with MPD syndrome. Analysis of condylar movements during chewing were also performed in 9 normal and 20 abnormal subjects. The results were as follow; 1. Subjects with TMJ abnormalities tended to show abnormal chewing patterns when chewing at their non-abnormal sides. 2. TMJ abnormality of each different type tended to show its respective characteristic chewing pattern. 1) Subjects with osteoarthrosis and reciprocal click without condylar posterior dislocation tended to show deviation of the turning point to the non-chewing side, with a convex opening path in the frontal plane and a lack of anteroposterior width in the sagittal plane. This finding was associated with the limitation in movement of the abnormal-side condyle. 2) Subjects with reciprocal click with condylar posterior dislocation tended to show a concave opening path and reversed or cross-over patterns in the frontal and horizontal planes, respectively. This finding was associated with the movement of the abnormal-side condyle in the medio-anterior direction during the initial phase of opening. 3) Subjects with closed lock without condylar posterior dislocation tended to show deviation of the turning point to the non-chewing side, with a concave opening path in the frontal plane and a lack of anteroposterior width in the sagittal plane. This finding was associated with the severe limitation in movement of the abnormal-side condyle. 4) Subjects with closed lock with condylar posterior dislocation characteristically tended to show reversed or cross-over patterns in the horizontal plane. This finding was associated with the movement of the abnormal-side condyle in the medio-anterior direction during the initial phase of opening. However, this movement was smaller than that of the reciprocal click. 3. Subjects with MPD syndrome showed chewing patterns similar to those of normal subjects. From the results, close relationships were found between chewing movements and TMJ abnormalities.