Magnetic resonance imaging assessment of the temporomandibular joint in disk displacement

Intraobserver reliability and validity of a single ultrasonic measurement of the lateral condyle-capsule distance in the temporomandibular joint

PURPOSE

The purpose of the study was to examine the reliability and validity of a single lateral condyle-capsule distance (LCCD) measurement while saving on economic costs and clinical resources.

METHODS

A longitudinal test-retest design was used to assess the reliability and validity of single-examiner measures over 72 TMJ sonographic analyses. Intraclass correlation coefficients (ICC) and a Bland-Altman plot were used to study reliability and validity, comparing the first measurement of the LCCD to the mean of 3 measurements taken one week later by the same examiner.

RESULTS

ICC show intraobserver reliability of 0.981, 95% confidence intervals (CI) of 0.969 to 0.988. The mean difference between the ultrasound measurements is 0.019 mm (95% CI 0.0005-0.0383) with a standard deviation of 0.080 mm, demonstrating robust validity. The 95% Limits of Agreement (LoA) are - 0.138 for the lower limit and 0.177 for the upper. Mean relative error is 0.009 mm.

CONCLUSION

Intraobserver reliability of a trained examiner is very high in the single measurement of the LCCD and validity is significant compared to more complex methods. The risk of bias is low since the mean of three LCCD measurements is calculated as opposed to recording only one single measurement.

Arthroscopic Disk Repositioning After Failed Open Disk Repositioning

PURPOSE

Open disk repositioning has been long achieving excellent functional and stability outcomes. However, still remains some relapses for whom a second open surgery is often challenging. This study aimed to evaluate the effectiveness of arthroscopic disk reposition as an alternative surgery for unsuccessful cases of anterior disk displacement (ADD) after an initial open disk repositioning.

MATERIALS AND METHODS

This retrospective study included all patients who underwent secondary arthroscopy for disk repositioning of the relapsed ADD after an initial open surgery between January 2012 to June 2017. The redo arthroscopic disk repositioning and suturing procedure was the primary predictor input variable in this study. Outcome evaluation was based on both clinical (visual analog scale and maximal interincisal opening) and magnetic resonance imaging data.

RESULTS

Twenty-seven joints fulfilling the inclusion criteria were included. A significant improvement was detected at 24-month postoperatively compared with the baseline visual analog scale. The maximal interincisal opening showed a statistical improvement from 25.07 mm preoperatively to 38.44 mm at 24-month postoperatively. Twenty-six joints maintained a stable disk position with only 1 joint relapsed to ADD without reduction.

CONCLUSION

Arthroscopic disk reposition and suturing technique is a reliable and effective repeat surgery after failed initial open disk repositioning for management of ADD.

Classification of temporomandibular joint internal derangement based on magnetic resonance imaging and clinical findings of 435 patients contributing to a nonsurgical treatment protocol

This prospective clinical study aimed to establish a new classification system for TMJ internal derangement based on MRI in correlation with clinical findings contributing to a nonsurgical treatment protocol. A consecutive sample of 435 internal derangement patients was enrolled in the study. Clinical and MRI studies were used to establish the new classification system. A total of 747 joints were classified according to our staging system and received treatment according to the associated nonsurgical treatment protocol. The primary outcome variables were maximum voluntary mouth opening and visual analogue scale pain scores. The secondary outcome variable was joint sound. Statistical analysis of the differences between pretreatment and posttreatment measurements showed an increase in mouth opening throughout the study period (P < 0.001 at 12 m posttreatment). Statistical analysis of the VAS scores showed a statistically significant decrease in all study groups during all study periods, with P < 0.0001 at 12 months posttreatment. Statistical analysis of joint sounds showed significant improvement during all study periods. The new classification system is a simple, & reasonable including a detailed description of all the pathologic changes of the joint. The nonsurgical treatment protocol was Simple, effective and specific depending on the pathological changes in joint.

Ultrasonography: A step forward in temporomandibular joint imaging. A preliminary descriptive study

Ultrasonography (USG) is a cost-effective and noninvasive imaging modality commonly employed for imaging the abdominal region and extremities. Currently, with the availability of higher frequency probes and higher resolution devices, USG imaging of the temporomandibular joint (TMJ) looks promising.

The aim is to evaluate and demonstrate the role of USG as an imaging modality of TMJ by visualizing the static and dynamic relationship of the joint, assessment of joint space and eliciting reproducibility at both open and closed mouth positions.

30 volunteers were selected based on the inclusion criteria in line with the research diagnostic criteria/temporomandibular disorders guidelines. High-resolution USG (≥12 MHz) of the right TMJ (chosen for uniformity) was done in the left decubitus position on (n=30) volunteers. The joint disc movement was directly visualized during opening and closing motions. The vertical joint space was assessed using the firmware and accurate reproducibility was checked. At the closed mouth position, the measured values ranged from 0.2 mm to 0.7 mm with a median of 0.05 cm and a mean of 0.4±0.15 mm. At the position of maximal mouth opening, the measured values ranged from 0.9 mm to 1.5 mm with a median of 1.1 mm and a mean of 1.1±0.17 mm. USG enables visualization of the dynamic relationship between joint structures, with particular importance to the condyle and disc position. The articular disc appears on the USG as a thin layer of hyperechogenicity surrounded by a hypoechoic halo, located between 2 hyperechoic lines viz, the condyle and the articular eminence We recommend ultrasonographic imaging as a noninvasive diagnostic technique with relatively high specificity for patients with temporomandibular disorders.

Internal derangement as a predictor of provoked pain on mouth opening: A magnetic resonance imaging study

Purpose

This study investigated the relationship between pain and internal derangement in temporomandibular disorder (TMD) patients using magnetic resonance imaging (MRI).

Materials and Methods

This study analyzed 356 TMD patients (712 temporomandibular joints [TMJs]). The inclusion criteria were the presence of spontaneous or provoked pain on one or both TMJs and having undergone MRI. The patients with provoked pain were divided into 3 groups: pain on palpation, pain on mouth opening, and pain on mastication. MRI was performed using a 1.5-T scanner. T1- and T2-weighted parasagittal and paracoronal images were obtained. According to the findings on the T1-weighted images, another 3 groups were created based on internal derangement: normal, disc displacement with reduction, and disc displacement without reduction. The MRI findings were independently interpreted by 2 experienced oral and maxillofacial radiologists at 2 different times. Statistical analysis was performed by the chi-square test using SPSS (version 12.0; SPSS Inc., Chicago, IL, USA).

Results

Provoked pain on mouth opening was found to be correlated with internal derangement in TMD patients (P<.05). However, spontaneous pain and provoked pain on palpation or mastication were not associated with internal derangement (P>.05).

Conclusion

These results suggest that internal derangement was a significant predictor of provoked pain on mouth opening.

Efficacy of plain radiographs, CT scan, MRI and ultra sonography in temporomandibular joint disorders

The complexity of structure and functions of the Temporomandibular Joint (TMJ) make the diagnosis of its diseases/disorders difficult. Remarkable progress made in the field of imaging of this joint led us to compare four imaging modalities viz. plain radiographs, CT scan, MRI and ultrasound. We found that MRI was most specific and sensitive for interpretation of soft tissue and inflammatory conditions in the joint, whereas CT examination produced excellent image for osseous morphology and pathology. Plain X-rays are useful for destructive bony changes and sonography is a good in aid in diagnosing disc derangement and is very economical.

Internal derangement of the temporomandibular joint: is there still a place for ultrasound?

OBJECTIVE

The aim of this study was to assess the diagnostic value of articular sounds, standardized clinical examination, and standardized articular ultrasound in the detection of internal derangements of the temporomandibular joint.

STUDY DESIGN

Forty patients and 20 asymptomatic volunteers underwent a standardized interview, physical examination, and static and dynamic articular ultrasound. Sensitivity, specificity, and predictive values were calculated using magnetic resonance as the reference test.

RESULTS

A total of 120 temporomandibular joints were examined. Based on our findings, the presence of articular sounds and physical signs are often insufficient to detect disk displacement. Imaging by static and dynamic high-resolution ultrasound demonstrates considerably lower sensitivity when compared with magnetic resonance. Some of the technical difficulties resulted from a limited access because of the presence of surrounding bone structures.

CONCLUSIONS

The present study does not support the recommendation of ultrasound as a conclusive diagnostic tool for internal derangements of the temporomandibular joint.

Biometric parameters of the temporomandibular joint and association with disc displacement and pain: a magnetic resonance imaging study

The aim of this study was to evaluate the relationship between biometric parameters of the components of the temporomandibular joint (TMJ), articular disc displacement, and TMJ pain. Magnetic resonance imaging (MRI) examinations of 185 patients were assessed (39 males and 146 females (370 TMJs), mean age 41.3 years, range 18-79 years). The antero-posterior length of the condyle was measured in its medial and lateral regions, as well as the transverse length of the condyle. Possible associations between linear measurements of the condyle, presence of disc displacement, and joint pain were tested. Although pain was more commonly reported among patients with disc displacements, this association was not statistically significant. We found statistically significant associations showing that the antero-posterior length of the condyle at the lateral pole (D1L), the antero-posterior length of the condyle at the medial pole (D1M), and the transverse length of the condyle (D2) were higher among patients without disc displacements when compared to those with unilateral or bilateral displacements. This study showed that disc displacement was associated with smaller condyles in the antero-posterior and transverse dimensions when compared to condyles in subjects with normal disc position.

Clinical and MRI investigation of temporomandibular joint in major depressed patients

OBJECTIVE

The aim of the present study was to describe the clinical and MRI findings of the temporomandibular joint (TMJ) in patients with major depressive disorders (MDDs) of the non-psychotic type.

METHODS

40 patients (80 TMJs) who were diagnosed as having MDDs were selected for this study. The clinical examination of the TMJs was conducted according to the research diagnostic criteria and temporomandibular disorders (TMDs). The MRIs were obtained bilaterally in each patient with axial, parasagittal and paracoronal sections within a real-time dynamic sequence. Two trained oral radiologists assessed all images. For statistical analyses, Fisher's exact test and χ(2) test were applied (α = 0.05).

RESULTS

Migraine was reported in 52.5% of subjects. Considering disc position, statistically significant differences between opening patterns with and without alteration (p = 0.00) and between present and absent joint noises (p = 0.00) were found. Regarding muscular pain, patients with and without abnormalities in disc function and patients with and without abnormalities in disc position were not statistically significant (p = 0.42 and p = 0.40, respectively). Significant differences between mandibular pathway with and without abnormalities (p = 0.00) and between present and absent joint noises (p = 0.00) were observed.

CONCLUSION

Based on the preliminary results observed by clinical and MRI examination of the TMJ, no direct relationship could be determined between MDDs and TMDs.

How should the articular disk position be analyzed?

PURPOSE

To compare 2 methods used to determine the disk position based on sagittal magnetic resonance images.

PATIENTS AND METHODS

A cross-sectional study of patients with the signs and symptoms of temporomandibular disorders was conducted. The patients' ages and gender distributions were collected. The disk position diagnosis from the clinical examination was considered the primary outcome. Three observers evaluated the presence of anterior displacement on magnetic resonance images according to 2 criteria: method 1 (12-o'clock position) and method 2 (location of the intermediate zone). To assess the intraobserver variability of the 2 methods, the examiners evaluated the same magnetic resonance images at the beginning of the study (time 1) and 40 days later (time 2). The intraobserver agreement was assessed using the observed agreement and the kappa statistic. McNemar's test was used to assess the differences between each method and the clinical examination findings (P < .05). The accuracy, sensitivity, specificity, and positive and negative predictive values were calculated by comparing the diagnosis from each method with that from the clinical examination (considered the reference standard).

RESULTS

The final sample was composed of 20 subjects with a mean age of 33.0 ± 33.7 years; 3 were men (15%) and 17 were women (85%). A statistically significant difference between the 2 methods was found. Method 1 yielded a greater percentage of anterior displaced disks (52.5%). The agreement between the clinical diagnosis and method 1 was lower (70.0%) than that between the clinical diagnosis and method 2 (87.5%). No statistically significant difference was found between the clinical diagnosis and method 2.

CONCLUSION

The disk position should be judged according to the intermediate zone criterion.

Diagnostic value of ultrasonography in temporomandibular disorders

PURPOSE

The purpose of this study was to determine the diagnostic value of ultrasonographic imaging (USI) in temporomandibular disorders.

PATIENTS AND METHODS

USI and magnetic resonance imaging (MRI) were performed in 182 temporomandibular joints (TMJs) of 91 patients who were referred for treatment. After a detailed clinical examination, patients who were clinically diagnosed with TMJ disc derangement were referred to the radiology department for MRI and USI examinations. USI and MRI diagnoses of disc displacement were compared, using clinical diagnosis as the golden standard. The overall agreement between USI and MRI results was evaluated.

RESULTS

Compared with the clinical diagnosis, MRI showed a sensitivity of 85%, specificity of 62%, and an accuracy of 80% in the detection of internal derangements. The positive predictable value, negative predictive value, and likelihood ratio were 88%, 54%, and 2.29, respectively. Compared with the clinical diagnosis, USI showed a sensitivity of 69%, specificity of 80%, and accuracy of 71% in the detection of internal derangements. The positive predictable value, negative predictive value, and likelihood ratio were 92%, 42%, and 3.45, respectively. Comparing the agreements between the MRI and USI diagnoses of internal derangement, the κ value was found to be 0.36, indicating poor reliability (P < .001).

CONCLUSION

USI, a noninvasive and dynamic imaging method, is a reliable method in evaluating the position of the disc in TMJ disc derangements. Better visualization of joint structures and more reliable results with higher sensitivity and accuracy can be achieved with high-resolution devices (≥12 MHz).

Muscular and condylar response to rapid maxillary expansion. Part 3: magnetic resonance assessment of condyle-disc relationship

INTRODUCTION

The aim of this prospective study was to assess temporomandibular joint (TMJ) condyle-disc positions at the sagittal and coronal planes of magnetic resonance images (MRIs) before and after rapid maxillary expansion (RME).

METHODS

The study included 18 subjects (11 girls, 7 boys) with a mean age of 12.54 years with unilateral or bilateral posterior crossbite that included at least 3 posterior teeth. The clinical and radiographic assessments of the TMJ were done before (T1) and 18 weeks after (T2) RME. A Haas-type expansion appliance was used for an average treatment time of 3.5 weeks.

RESULTS

A visual MRI analysis of pretreatment condyle-disc positions showed that 8 TMJs had medial disc displacement, 3 had anteromedial disc displacement, and 2 had lateral disc displacement. The disc positions remained unchanged at T2 except in 1 subject, who developed unilateral anterior disc displacement. Unilateral joint sounds developed in 3 subjects without changes in the disc positions.

CONCLUSIONS

Posterior crossbite can be considered a minor risk factor for temporomandibular disorder (TMD). RME is neither a risk factor nor a prevention for TMD. Coronal MRIs contribute complementary information for optimal diagnosis of TMD.

Condylar and disk position and signs and symptoms of temporomandibular disorders in stress-free subjects

BACKGROUND

The authors conducted a study in subjects who tested free of psychological stress to determine the position of the condyle and whether that position was related to signs and symptoms of temporomandibular disorders (TMDs).

METHODS

Forty subjects underwent psychological evaluation to ensure freedom from psychological stress. The authors evaluated tenderness of the masticatory muscles and temporomandibular joints (TMJs) by means of bimanual digital palpation, and they determined the positions of the condyle and disk by using magnetic resonance imaging.

RESULTS

A total of 23.75 percent of the condyles were displaced away from the centric position either anteriorly (3.75 percent) or posteriorly (20.00 percent). chi(2) analysis showed a relationship between the position of the condyle and displacement of the disk, as well as a relationship between the position of the condyle and tenderness of the TMJs.

CONCLUSION

Although these relationships proved significant, it cannot be assumed that displacement of the condyle away from the centric position is predictive of TMD.

CLINICAL IMPLICATIONS

Only two subjects were judged to have had TMJ internal derangement. Thus, the absence of psychological stress seems to have played a role in this finding.

Evaluation of temporomandibular joint in stress-free patients

OBJECTIVES

The aetiology of temporomandibular disorders (TMD) is presently considered to be multifactorial, and stress has been regarded as an important factor in their onset. Many studies have evaluated the importance of stress in TMD; however, only patients with TMD and stress have been assessed. This study aimed at evaluating signs and symptoms of TMD in stress-free patients.

METHODS

The temporomandibular joints (TMJs) of 40 stress-free patients were evaluated during clinical examination and in MRI.

RESULTS

The individuals lived in an area without electric power supply or telephone services. They worked in agriculture and fishery. 77.5% of the patients presented normal mandibular function; 70% presented normal mandibular trajectory; 61.25% did not present sounds in TMJ and 93.75% did not present joint pain during palpation. Image screening showed that 70% of TMJ presented normal disc position. Only one patient (1.25%) presented TMD.

CONCLUSIONS

The absence of stress is a strong factor for the non-development of TMD.

Magnetic resonance imaging in the evaluation of temporomandibular joint disc displacement--a review of 144 cases

One hundred and forty four patients underwent magnetic resonance imaging (MRI) for evaluation of suspected internal derangement (ID) of the temporomandibular joint (TMJ). All scans were performed on a state-of-the-art scanner by highly experienced technologists and evaluated by a single Head and Neck/Maxillofacial radiologist. Seventy-nine percent of patients were female and 21% male. Age distribution of the cases was bi-modal with first peak at 20-30 years of age and second peak at 50-60 years of age. Of the 82.5% of cases with disc displacement, 59.5% demonstrated reduction with opening and 40.5% did not reduce. Anterior disc displacement is common (44%) and sideways displacement rare (4%). Antero-lateral displacement was the second commonest type of displacement (29%) probably related to the weakness of the lateral disc attachment.

Herbst appliance therapy and temporomandibular joint disc position: A prospective longitudinal magnetic resonance imaging study

INTRODUCTION

The objective of this prospective study was to verify changes in the position of the temporomandibular joint (TMJ) disc by means of magnetic resonance images (MRIs) in adolescent patients treated with the Herbst appliance.

METHODS

Twenty consecutive Class II Division 1 patients treated with Herbst appliances were selected for the study. MRIs were analyzed at 3 stages: immediately before Herbst treatment (T1), 8 to 10 weeks after appliance placement (T2), and at the end of the 12-month Herbst treatment, immediately after appliance removal (T3).

RESULTS

Class I or overcorrected Class I dental-arch relationships were observed after Herbst therapy. The qualitative evaluation showed that each patient had the disc within normal limits at T1. At T2, a slight tendency toward disc retrusion because of mandibular advancement was observed, but, at T3, the disc returned to normal, similar to T1 values. By using a quantitative evaluation, parasagittal MRIs (central, medial, and lateral slices) of the TMJs showed that there was no change of disc position from T1 to T3, except in the central slice, which had a retrusive position of the articular disc at T3.

CONCLUSIONS

During the 12-month period of Herbst appliance treatment, mild changes in the position of the disc occurred in patients whose articular discs were within normal limits at T1. These changes were within normal physiological limits when evaluated in the short term.

Ultrasonography of the temporomandibular joint: Comparison of findings in patients with rheumatic diseases and temporomandibular disorders. A preliminary report

OBJECTIVE

The objective of the study was to compare findings from ultrasonography (US) of the temporomandibular joint (TMJ) in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and temporomandibular disorders (TMD).

STUDY DESIGN

US assessment of the temporomandibular joints was bilaterally performed in 68 patients (22 with RA, 11 with PsA, and 35 with TMD). All the TMJs were assessed for the presence of disc displacement, effusion, and changes of the condylar profile, and the prevalence of such abnormalities was compared across the 3 groups of patients. To confirm generalizability of results, US findings were also compared with those of magnetic resonance (MR), taken as the standard of reference.

RESULTS

Prevalence of disc displacement and changes in condylar profile were similar between patients with rheumatic diseases and temporomandibular disorders, while effusion was significantly more present in TMJs of TMD patients. Sensitivity of US to detect TMJ abnormalities was acceptable, while specificity was low for condylar alterations.

CONCLUSIONS

Temporomandibular joint involvement in patients with rheumatic diseases seems to be similar to that described in subjects with temporomandibular disorders. Ultrasonography confirmed to be an accurate technique to detect disc displacement and effusion within the temporomandibular joint, but not to detect condylar abnormalities.

Comparison of ultrasonography and magnetic resonance imaging in the evaluation of temporomandibular joint disc displacement

The aim of this work was to evaluate the accuracy and reliability of ultrasonography in the diagnosis of temporomandibular joint (TMJ) disc position abnormalities compared with magnetic resonance imaging (MRI). Participants in this study were 41 consecutive patients with signs and symptoms of temporomandibular disorders. All 82 TMJs were evaluated to detect disc position abnormalities by means of ultrasonography and MRI, performed by blinded operators. The accuracy of ultrasonography was evaluated with respect to MRI. Ultrasonography demonstrated good accuracy in the evaluation of disc position, showing a sensitivity of 65.8% and a specificity of 80.4%, resulting in a positive likelihood ratio of 3.35, a negative likelihood ratio of 0.42, and a diagnostic odds ratio of 7.97. The predictive positive and negatives values were respectively 77.1% and 70.2% and the overall agreement between the two radiological techniques was 73.1%. Ultrasonography proved to be accurate in detecting normal disc position and the presence of abnormalities in disc-condyle relationship but not so useful for the distinction between disc displacement with and without reduction.

Comparison of ultrasonography with magnetic resonance imaging in the diagnosis of temporomandibular joint internal derangements: a preliminary investigation

OBJECTIVE

This study aimed to compare ultrasonography (US) with magnetic resonance imaging (MRI) with respect to the diagnosis of temporomandibular joint (TMJ) internal derangements.

STUDY DESIGN

The study group consisted of 23 patients with a chief complaint of TMJ discomfort who were tentatively diagnosed by means of head-neck examination as having TMJ internal derangements and a control group of 9 volunteers who had no sign of TMJ internal derangements. All the patients were then examined by means of MRI and US.

RESULTS

The results showed perfect agreement between MRI and US in the diagnosis of TMJ internal derangements (kappa = 1.000; P =.0001).

CONCLUSION

MRI and US can be used to define the disk and its position, as well as the presence of TMJ internal derangements.

Fränkel appliance therapy and the temporomandibular disc: a prospective magnetic resonance imaging study

This prospective clinical study assessed the effect of the Fränkel Functional Regulator-II (FR-II) treatment on the position and shape of the articular disc of the temporomandibular joint. The sample included magnetic resonance images of 112 temporomandibular joints taken initially (T1) and after 18 +/- 1 months (T2). The subjects were 56 white Brazilian children who were beginning their pubertal growth spurt. They had Class II Division 1 malocclusions and were selected from 800 children in neighborhood schools. They were randomly dichotomized into either the treated group (treated with the FR-II for 18 months) or the control group (not treated during the observation period). Our findings showed a low prevalence (3.57%) of disc displacement in the 112 temporomandibular joints. Mandibular propulsion with the FR-II had no unfavorable effect on the temporomandibular joints of the treated group; 100% of the patients kept an upper and interposed disc position (closed and open mouth, respectively) at T1 and T2. The control group had 7.1% partial anterior medial disc displacement, both at T1 and T2. Regarding disc morphology, the control group showed biconcave-shaped discs in 82.1% of the joints, statistically similar to the treated group (89.3%) at the beginning of the observation period. At T2, the articular disc morphology of the control group was unchanged, but that of the treated group was significantly more normal (P =.016), progressing from nonbiconcave at T1 (10.7%) to biconcave at T2 (100%). Our results showed that disc displacement is not a complication of functional appliance therapy; in fact, such treatment might help some children with incipient temporomandibular disorders.

A prospective study of Twin-block appliance therapy assessed by magnetic resonance imaging

Forty children displaying Class II Division 1 malocclusion were involved in a prospective magnetic resonance image investigation to evaluate the effects of Twin-block functional appliances on the temporomandibular joints. None of these children had clinical signs or symptoms of temporomandibular disorders. Nineteen children were treated with a Clark Twin-block appliance for 6 months; the other 21 children received no treatment and served as controls. Comparison between control and Clark Twin-block groups suggested that reduction of the condylar axial angle represents a feature of untreated Class II growth patterns, whereas axial angle stability with Clark Twin-block therapy may suggest alteration of condylar growth direction. Condyles that were positioned at the crest of the articular eminence by the Clark Twin-block at the beginning of treatment had reseated back into the glenoid fossa after 6 months. However, 75% of the condyles were more anteriorly positioned in successfully treated Clark Twin-block cases. There was no clear evidence of remodeling of the glenoid fossa at the eminence as a result of Clark Twin-block treatment. The initial prevalence of disk displacements for the combined groups was 7.5% anterior, 5% medial, and 12.5% for lateral disk displacement. Clark Twin-block therapy had neither positive nor negative effects on disk position, and there was no convincing evidence that the disk was recaptured.

Comparison of clinical and magnetic resonance imaging diagnosis in patients with disk displacement in the temporomandibular joint

OBJECTIVE

The purpose of this study was to validate the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) for the diagnostic subgroup of disk displacement with reduction, with magnetic resonance imaging used as a gold standard.

STUDY DESIGN

The diagnoses from the clinical examination of 78 joints in 39 patients, each with disk displacement with reduction in at least one TMJ, were compared with magnetic resonance imaging diagnoses. The readers of the magnetic resonance images were blinded to the clinical diagnoses. The data analysis included kappa statistics and calculation of predictive values.

RESULTS

The predictive value of the RDC/TMD for disk displacement with reduction was 0.65. For disk displacement alone-the movement of the disk on opening not being considered-the predictive value was 0.92. The diagnostic agreement between RDC/TMD and magnetic resonance imaging diagnoses for all joints examined was 53.8%. Most of the disagreement was due to false negative clinical diagnoses for asymptomatic joints.

CONCLUSIONS

A positive RDC/TMD examination is predictive for internal derangement but not reliable with regard to the type of disk displacement; such examination is therefore of limited value in determining the true disk position and its functional movements.

MR of 732 TMJs: anterior, rotational, partial and sideways disc displacements

OBJECTIVE

The purpose of this study was to determine the prevalence of anterior, sideways, rotational and partial anterior disc displacements, as well as degenerative changes in patients with clinical signs and symptoms of internal disorders.

MATERIALS AND METHODS

732 MR Images of temporomandibular joints (TMJ) were produced for 366 symptomatic patients. Image analysis included assessment of disc positions and mobility, as well as recapture in coronal and mediolaterally divided sagittal planes in closed and open positions.

RESULTS

Of these images, 545 TMJ showed an internal derangement comprised of 52% anterior disc displacements without reduction, 26% anterior disc displacements with reduction, 11% partial anterior disc displacement, 5% pure sideways displacements and 4% stuck discs. Rotational disc displacements were observed in 34% of the anterior disc displacements without reduction group and in 53% of the anterior disc displacements with reduction group. A total of 97% of the partial anterior disc displacement occurred laterally. Degenerative changes increased with age, mainly in the anterior disc displacements without reduction group.

CONCLUSION

Magnetic resonance imaging (MRI) investigations show that the disc is subject to a great variety of displacements and that there is a need for further research to refine the clinical therapy for TMJ internal derangements.

A new coronal imaging plane for magnetic resonance imaging of the temporomandibular joint disc

We found that identification of an anterior displaced disc of the temporomandibular joint was difficult with traditional coronal oblique MR images. We describe the use of a new coronal oblique imaging plane which overcomes this problem.

Variability of disk position in asymptomatic volunteers and patients with internal derangements of the TMJ

This study determined the variability of temporomandibular joint (TMJ) disk position in medial, central, and lateral aspects of the joint using magnetic resonance imaging (MRI). Subjects had clinical evidence of reciprocal TMJ clicking (N = 123) or restricted mandibular motion (N = 52). Eighty-nine asymptomatic volunteers provided a control group. Disk position was quantified on MRI by measuring the angle formed by a line through the middle of the condyle and perpendicular to the Frankfort plane and a line through the same midpoint of the condyle and tangential to the posterior-most aspect of the disk. The disk position in asymptomatic TMJs varied considerably with a tendency toward farther anterior placement in more lateral images. In 47 TMJs from a total of 52 TMJ5 (90%), restricted mobility was associated with anterior disk displacement (ADD) without reduction. The disk position demonstrated a mean displacement of 77 degrees without significant differences at the medial and lateral aspects of the condyle. One hundred TMJs from a total of 123 TMJs (81%) with reciprocal clicking demonstrated ADD with reduction. Tomograms revealed larger lateral displacements or rotational displacements in these joints, whereas medial images frequently showed similar ranges of disk positions as compared with asymptomatic TMJs. The results suggest that disk positions of up to +15 degrees on medial tomograms and +30 degrees on lateral tomograms should be regarded as normal variations. Furthermore, multisection analysis of all parasagittal images improved the separation between disk displacement and asymptomatic TMJs.