TMJ sounds: are they a common finding or are they indicative of pathosis/dysfunction?

Association between craniofacial asymmetry and unilateral temporomandibular joint sounds in adult patients using 3D-computed tomography

OBJECTIVES

The purpose of this study was to investigate the possible relationship between unilateral temporomandibular joint (TMJ) sounds and craniofacial asymmetry, using 3D-computed tomography (CT) measurements.

SUBJECTS AND METHODS

Forty-one reconstructed 3D-CT models of adult subjects were measured to analyze craniofacial asymmetry. Subjects were divided into two groups depending on the presence (n = 20) or absence (n = 21) of unilateral joint sounds, and the results compared using the Mann-Whitney U-test. To investigate the association between these parameters, the Pearson correlation coefficient was calculated.

RESULTS

Asymmetries in the maxillary and mandibular structures were statistically significant (P < 0.05) for subjects with unilateral TMJ sounds and for controls, except in the case of maxillary rotation and mandibular ramus height (P > 0.05). The highest deviations found were frontal and lateral ramal inclination, goniac angle and canting of occlusal plane.

CONCLUSIONS

Adult patients with unilateral joint sounds may have skeletal jaw asymmetry and a canted occlusal plane.

Correlation of occlusal factors and condyle position asymmetry with signs and symptoms of temporomandibular disorders in young adults

The role of the occlusion in the etiology and prevalence of temporomandibular disorders (TMD) has not been conclusively demonstrated. Occlusal factors and condyle position asymmetry as deduced from computed tomography (CT) axial scans were correlated with signs and symptoms of TMD in 49 young adults (mean age 24 years, range 15-33 years) with complete or almost complete dentition. A statistically significant correlation was noted between these signs and symptoms and occlusal variables describing asymmetry (the amount and lateral deviation of the slide from the retruded contact position (RCP) to the intercuspal position (IP), deviation of protrusion and asymmetry in bilateral cuspid occlusion). It seems that occlusal discrepancy can be a predisposing factor to TMD, especially when it is asymmetrically expressed.

Vibration analysis of the temporomandibular joints with meniscal displacement with and without reduction

The vibrations of 102 joints demonstrating meniscal displacement with either early or late reduction (MDR-early/MDR-late) and 70 joints displaying meniscal displacement without reduction either incomplete or complete (MD-incomplete/MD-complete) were analyzed and compared to 83 arthrographically normal but symptomatic joints (NID) using electrovibratography (EVG). The total power density of the vibration [I(T)], peak power density [I(max)] and power density at each 50Hz range between O to 600 Hz [I(f)] showed the highest in the MDR-late group followed by the MDR-early group, suggesting that the level of vibration is related to the degree of disk displacement and reduction. The wave characteristic parameters such as the correlation coefficients between I(T) and each I(f) showed higher correlation at higher frequency ranges as the degree of disk displacement progressed, from MDR-early to MDR-late to MD-incomplete. The diagnostic sensitivity of EVG when using I(T) as a determining parameter was 96.6% for the MDR-early group, 91.8% for the MDR-late group, 77.8% for the MD-incomplete group and 57.4% for the MD-complete group with the specificity for the NID group at 75%.

Vibrations in the temporomandibular joints in patients examined and treated in a private clinic

Patients indicated for examination, evaluation and treatment of the temporomandibular joint (TMJ) in the Centro de Diagnostico e Tratamento da ATM (CDTATM) were submitted to computerized BioPAK system tests. Special attention was placed on the SonoPAK test (electrovibratography), seeking to evaluate the articular sound problem in differentiated patients for specific TMJ treatment. The percentage of sounds (148 joints, 74 patients) was high (75.67% in the opening movement and 50.00% in the closing movement) which suggests the necessity to give more attention to the TMJ sounds during a clinical exam. And also, if possible, give more attention to the utilization of specific tests to obtain a clear definition of the type of sound the patient presents.

Vibration of the temporomandibular joints with normal radiographic imagings: comparison between asymptomatic volunteers and symptomatic patients

In order to estimate the effect of a background noise during temporomandibular joint (TMJ) vibration analysis, 40 recordings from sensors not attached to subjects and sensors attached to subjects without any jaw movement were evaluated. Both of them showed very small energy density, close to 0, throughout 0 to 600 Hz and flat frequency distributions. To evaluate the vibration energy of asymptomatic TMJs with normal joint anatomy and symptomatic TMJs with normal arthrographic imagings, 20 TMJs from 10 clinically normal and asymptomatic volunteers with bilateral normal TMJ computerized tomography (CT) scanning (N-control) were analyzed at four mandibular positions. Results from intercuspal position and maximal opening were identical to the background noise. Results from closing and opening phase showed higher energy, especially below 150 Hz, than the background noise. Surface vibrations of 83 TMJs from patients with arthrographically normal imagings but having symptoms (NID) showed significantly higher energy than the N-control group above 300 Hz. When the total vibration energy (I(T)) is used to set the threshold for the separation of internal derangement, at I(T) = 2.06, the diagnostic specificity for the NID group is 75%, while the diagnostic sensitivity is 82.4% for internal derangement. At the same time, 98.3% of the N-control group was involved below the threshold.

A clinical study of temporomandibular joint (TMJ) vibrations in TMJ dysfunction patients

Using electrovibratography (EVG), the vibrations of 309 temporomandibular joints (TMJs) from 213 patients with clinical symptoms of temporomandibular joint dysfunction (TMD) were compared to TMJ arthrography. Of 309 imaged joints, 221 had an internal derangement (ID) and 88 were arthrographically normal (NID). Among the parameters derived from the power spectrum function of joint vibration, the total power density from 0 to 600 Hz (I(T)), the peak power density I(max)), and the power density at each 50 Hz frequency range (I(f)), each of these was significantly greater in ID than in NID patients. The frequency range that included (I(max) and the frequency range containing 50%, 75%, and 90% of I(T) was significantly lower in ID than in NID patients. The diagnostic sensitivity and specificity of a patient's perception of TMJ sounds were 43% and 80%, respectively, while those for a doctor's perception were 54% and 72%. When using I(T) as a parameter, the sensitivity and specificity of the EVG were 75% and 77%, respectively. By using these parameters of TMJ vibration energy analysis, a separation may be made between patients with normal joint anatomy and internal derangement.

An analytic method for evaluating condylar position in the TMJ and its application to orthodontic patients with painful clicking

The purpose of this study was to develop a new method for evaluating the three-dimensional position of the mandibular condyle relative to the glenoid fossa and further to investigate its clinical application to orthodontic patients with temporomandibular disorders (TMD). A three-dimensional configuration of the temporomandibular joint was constructed by 108 triangles for the condyle and 180 triangles for the glenoid fossa. The shortest distance between the condyle and glenoid fossa (CGFD) was calculated in the model along a line perpendicular to the center of gravity of a triangle on the condyle. The CGFD was determined in the anterior, posterior, middle, lateral, and medial areas on the condyle. Preliminary investigation revealed that the present technique is accurate, regardless of condylar rotation and/or inclination to the tomographic table. The technique was applied to the diagnosis of orthodontic patients with painful clicking and TMD. It is shown that the present approach provides a method for evaluating the positional relationship between the mandibular condyle and glenoid fossa in patients with TMD.

Temporomandibular joint sounds: correlation to joint structure in fresh autopsy specimens

In an attempt to better understand the cause of different types of temporomandibular joint (TMJ) sounds, we recorded joint sounds from 27 fresh autopsy specimens, displayed the time frequency distribution of the sound as a three-dimensional graph, and correlated the sound character to morphologic observations at subsequent dissection. Eleven joints elicited sounds, and 16 joints were silent. All joints with sounds had different degrees of intraarticular changes. These ranged from disk displacement with reduction to displacement without reduction and arthrosis of the articular surfaces. Reciprocal clicking occurred both in joints with disk displacement with and without reduction, as well as in joints with arthrotic changes. Crepitation only occurred in joints with arthrosis and perforation. The sample was too small to demonstrate any statistically significant association between the joint sound classified as clicking or crepitation and joint structure types of joint pathosis in this small sample. A high frequency component to the sound appeared to be associated with arthrosis of the articular surfaces. It was concluded that joint sounds indicate joint abnormality but that the absence of joint sound does not exclude intraarticular pathosis.

[Longitudinal changes in the acoustic temporomandibular symptoms due to different procedures of orthognathic surgery]

A longitudinal study of TMJ sounds prior to and after combined orthodontic-orthognathic surgical procedures was carried out. The relative frequency of such sounds two days prior to operation (T0) and three months (T1), eight months (T2), 14.5 months (T3), and 25.5 months (T4) postoperatively remained--treatment-independently--largely unchanged. Chances in frequency between T0 and T4 showed only a nonsignificant tendency to differ in comparison with changes seen after orthodontic treatment (A) only. An analysis of individual changes revealed that after Le Fort I osteotomy (B) and bimaxillary procedures/posterior mandibular repositioning (D), no change in the preoperative sounds is to be expected. In contrast, following mandibular advancement (C) TMJ sounds first disappeared, in particular in the period immediately following operation (T0-T1), but also subsequently reappeared. The difference vis-a-vis group B (Le Fort I osteotomies) was statistically significant (group B vs. group C: p less than or equal to 0.01.