关节盘移位对颞下颌关节内应力分布的影响

目的 通过对不同关节盘移位的数值模拟,探究各种移位情况下颞下颌关节（temporomandibular joint,TMJ）内各结构的应力分布规律。方法 依据CT图像,建立包含下颌骨、全牙列、关节盘和关节软骨的正常TMJ三维有限元模型;参考关节盘前、后、外、内移位的临床特征,建立对应的4个模型。关节盘与关节软骨间考虑接触,用缆索元模拟下颌韧带和关节盘附着,施加正中咬合荷载。结果 前移位将导致关节盘中带产生过高的压应力,达到3.23 MPa;后、内、外移位时关节盘的整体应力水平比前移位和正常TMJ高;各种移位都使关节结节后斜面的应力值大幅度增加,但对髁突关节面的影响却不大。结论 各种移位都将导致关节盘和关节结节后斜面产生过高的应力,且后、内、外移位更为危险,更容易造成关节结构和功能的损伤。     

An assessment of the usefulness of jaw kinesiography in monitoring temporomandibular disorders: Correlation of treatment-related kinesiographic and pain changes in patients receiving temporomandibular joint injections

BackgroundThe authors conducted a study in patients with temporomandibular joint (TMJ) osteoarthritis to assess whether treatment-related changes in pain levels and chewing ability coincide with a change in jaw kinesiographic (KG) parameters.MethodsThe authors selected 34 patients with a diagnosis of TMJ osteoarthritis that met Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) to undergo a cycle of five weekly arthrocentesis procedures with injections of 1 milliliter hyaluronic acid. They performed a permutation test to assess the correlation between changes across time (from baseline to end of treatment) in two clinical outcome parameters—pain level and chewing ability—and changes across time in the KG outcome parameters.ResultsThe authors observed improvement across time in both chewing ability (F = 8.328; P = .005) and pain level (F = 10.903; P = .002). The authors observed no significant changes in any KG variables. With minor exceptions, no significant correlations were shown between changes in the clinical and KG parameters during the treatment period.ConclusionsTreatment-related changes in pain levels and chewing ability in patients with TMJ osteoarthritis do not coincide with changes in KG parameters.Practical ImplicationsIf one assumes pain variables to be the primary outcome measures in assessing treatment of TMJ osteoarthritis, KG recordings of the jaw are not useful for monitoring TMJ osteoarthritis in the clinical setting.     

Mandibular condylectomy with osteoarthrectomy with and without transfer of the temporalis muscle

Twenty-two patients with chronic arthritis and ankylosis of the temporomandibular joint (TMJ) were treated by resection of the condyle with osteoarthrectomy and interposition with a temporalis muscle flap. We compared them with 14 patients who were treated by condylectomy and osteoarthrectomy alone. All patients were evaluated prospectively. Most patients had had a previous operation on the disc. Variables investigated before and after operation were pain during mandibular movements (using a visual analogue score (VAS) of 1–10) and impaired mandibular function such as chewing and biting off (also using a VAS of 1–10). Maximum interincisal opening was measured with a ruler. Both groups of patients showed significant improvements in all the variables evaluated. Using the predefined success criteria, both methods showed good success rates with few complications. The patients treated by interposition of the temporalis muscle tended to do better, but not significantly so. Both methods induced occlusal changes and some needed dental treatment postoperatively.     

Analysis of mandibular motion following unilateral and bilateral alloplastic TMJ reconstruction

The purpose of this study was to analyse the masticatory patterns and range of motion (maximal incisal opening (MIO), protrusion and lateral excursion) in patients who have had unilateral and bilateral temporomandibular joint (TMJ) replacement with an alloplastic prosthesis, and compare them to each other and to normal controls. Mandibular motion was examined in 18 patients, who had undergone alloplastic TMJ reconstruction, 13 with a bilateral prosthesis and 5 with a unilateral prosthesis, and in 13 normal controls. A statistically significant difference (P < 0.01) for MIO and maximum lateral excursion was observed between the bilateral group and the control group. Maximum protrusion was only statistically significantly different (P < 0.05) between the bilateral group and the control group. For the unilateral group, a statistically significant difference (P < 0.01) was seen only with maximum contralateral excursion when compared with controls. No statistically significant difference existed in MIO and protrusion between the unilateral and bilateral groups. Even though maximum ipsilateral lateral excursion was greater for the unilateral group than either left or right maximum lateral excursion by the bilateral group, this difference was not statistically significant. This study provided an in vivo analysis of mandibular motion following alloplastic TMJ reconstruction.     

高渗葡萄糖关节上腔注射治疗颞下颌关节囊松弛（半脱位）和复发性脱位的临床应用

目的：探讨高渗葡萄糖硬化治疗颞下颌关节囊松弛（半脱位）和复发性脱位的效果。方法：采用50%葡萄糖注射剂行关节上腔注射治疗6例颞下颌关节半脱位的患者和7例复发性颞下颌关节脱位的患者,观察疗效;并对其治疗前后Fricton颞下颌关节紊乱指数进行评分,评价患者颞下颌关节功能的变化。结果：13例患者临床疗效满意,随访2月至半年无复发,治疗后患者的颞下颌关节紊乱指数明显改善。结论：采用50%葡萄糖注射剂行关节上腔注射治疗颞下颌关节半脱位和复发性脱位具有良好的效果。     

Immunohistochemical analysis of IL-1 Receptor 1 in the discs of patients with temporomandibular joint dysfunction

Objective Temporomandibular joint dysfunction (TMD) may affect a patient’s quality of life, and one of the etiologies can be anterior disc displacement with reduction (ADDwR) and anterior disc displacement without reduction (ADDWoR). Interleukin 1 Receptor 1 (IL-1R1) is a membrane receptor that plays an important role on initiating immune and inflammatory response by binding the agonists ligands of IL-1 alpha and IL-1 beta. Therefore, the aim of this study was to evaluate, through immunohistochemical analysis, the association of IL-1R1 with TMD.

Methods Thirty-nine human disc samples were collected and composed three different groups: ADDwR (n = 19), ADDwoR (n = 12), and control group (n = 8). The samples were immunostained with IL-1R1 antibody and evaluated on both quantity and intensity of staining.

Results There was a statistically significant difference (p < 0.05) between the control and test groups for both quantity and intensity of staining.

Conclusion IL1-R1 was associated with ADDwR and ADDwoR in TMD discs of humans.     

Synovial chondromatosis of the temporomandibular joint with glenoid fossa erosion: Disk preservation for spontaneous anatomical recovery

Synovial chondromatosis (SC) of the temporomandibular joint is a pseudoneoplastic condition characterized by benign cartilaginous metaplasia of synovial tissue mesenchymal residues with intra-articular nodule formation. TMJ involvement is rare. Interposition of loose bodies in the articular space can generate pressure, leading to glenoid fossa erosion with intracranial extension.The aim of this study was to present six SC cases with intracranial extension treated using a surgical procedure.All the patients were treated with open surgery. The superior compartment of the TMJ was opened widely to carefully remove the metaplasic mass. Temporal synovectomy was then performed. Attention was paid to preserving the integrity of the articular disc. The exposed dura mater was also preserved. No material was used to reconstruct the gap in the glenoid fossa.A 1-year follow-up showed no swelling or pain. Patients demonstrated good recovery of mouth opening, with improvement over previous mouth limitations. Morphological studies, performed using MRI and CT, showed complete anatomical recovery of the TMJ and total bone reconstruction of the glenoid fossa.Simple removal of intra-articular nodules, with TMJ arthroplasty and articular disk preservation, represents an efficient treatment option for full anatomical and functional recovery in synovial chondromatosis of the temporomandibular joint with glenoid fossa erosion of less than 1 cm².     

Communicating hydrocephalus induced by mechanically increased amplitude of the intraventricular cerebrospinal fluid pulse pressure: rationale and method

To elucidate some of the brain stem mechanisms involved in tongue motility, extracellular microelectrode recordings were made from single neurons in the region of the hypoglossal nucleus in 10 decerebrate and 23 anesthetized (chloralose) adult cats. The antidromic response characteristics and the synaptically evoked responses of 71 motoneurons that supplied tongue protrusive (P) or retrusive (R) muscles were documented. Protrusive motoneurons could be synaptically excited by temporomandibular joint (TMJ), glossopharyngeal (IX), and/or superior laryngeal (SLN) nerve stimuli, whereas R motoneurons could be activated by lingual and/or IX nerve stimulation. Conditioning effects revealed that the inhibition of the antidromic responses was shorter in duration than the inhibitory effects noted when synaptically evoked responses were conditioned. Conditioning stimuli delivered to the lingual, TMJ, IX, and SLN nerves were most effective in inhibiting the synaptically evoked responses of P and R motoneurons for conditioning-test intervals of as much as 400 ms. Those conditioning stimuli which also could synaptically activate a motoneuron tended to facilitate the cell's synaptically evoked responses at conditioning-test intervals of about 10 ms, whereas conditioning stimuli which did not synaptically activate the cell resulted in only the long-lasting inhibition.     

Transport distraction osteogenesis as a method of reconstruction of the temporomandibular joint following gap arthroplasty for post-traumatic ankylosis in children: a clinical and radiological prospective assessment of outcome

This clinical and radiographic study investigated the use of transport distraction osteogenesis in unilateral temporomandibular joint (TMJ) ankylosis patients. Six patients aged between 4 and 8 years were selected for the study; the mean preoperative maximal inter-incisal opening (MIO) was 3.5 mm without lateral and protrusive mandibular movements. The ankylotic mass along with the posterior border of the ascending ramus was exposed via ‘lazy-S’ incision. A gap arthroplasty was performed, followed by a ‘reverse L’ osteotomy on the posterior border of the ramus. In-house manufactured extraoral distraction devices were used for this prospective study. Follow-up clinical and radiographic evaluation was carried out for 13–27 months after completion of the activation period. After a mean follow-up of 19 months, the mean MIO was 29.1 mm and the lateral and protrusive movements changed from none to slight. Cone beam computed tomography images of all patients showed remodelled neocondyle created by transport distraction osteogenesis with no statistically significant differences observed for average cancellous bone density, trabecular number, and trabecular spacing between the neocondyle of the operated side (test) and the condyle of the non-operated side (control). Neocondyle formation by transport distraction osteogenesis using the in-house distraction device is a promising treatment option for TMJ reconstruction in ankylosis patients.     

Chondroma of the mandibular condyle-relapse of a rare benign chondroid tumour after 5 years' follow-up: case report

Chondroma of the mandibular condyle is rare and its signs and symptoms can mimic those of patients with more common disorders of facial asymmetry or dysfunction of the temporomandibular joint (TMJ). We report a case of chondroma of the mandibular condyle that presented as temporomandibular pain with malocclusion, and which relapsed 5 years after the initial treatment. To our knowledge only 7 cases of chondroma of the mandibular condyle have been reported in the last 70 years. This case is the eighth.