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This study was undertaken to investigate whether the quality of magnetic resonance images of the temporomandibular joint could be improved by scanning in oblique planes oriented according to the individual angle of the mandibular condyle (oblique images) instead of in the true anatomic sagittal and coronal planes (orthogonal images). Sagittal and coronal magnetic resonance images obtained by both methods in 21 patients were compared for image quality of the disk. In more than half the patients the oblique images demonstrated the anatomy of the disk better than the orthogonal images. Oblique images are therefore recommended.

A technique for maximizing the ability to perform direct sagittal CT scanning of the TMJ with the GE 8800 CT scanner gantry is described.

Internal derangements of the temporomandibular joint (TMJ) may be a significant factor in the etiology of painful dysfunction of the jaw and associated clinical symptoms. In a two-year prospective investigation, 170 TMJs in 85 patients were studied with plain tomography prior to arthrotomography. Arthritis was detected in 19 patients (22%), predominantly in the second to fourth decade of life, which correlated with internal derangements depicted by arthrotomography, operative findings, and histopathological examination of the condylar surface. The authors suggest that internal derangements related to meniscal dysfunction may be an important factor in the etiology of TMJ arthritis.

The accuracy of coronal and sagittal magnetic resonance (MR) imaging was examined in the assessment of rotational and sideways displacements of the temporomandibular joint (TMJ) disk. Rotational disk displacement implies a combination of anterior and medial or lateral displacements, whereas sideways displacement implies pure medial or lateral displacement without an anterior component. Multiple 3-mm-thick coronal and sagittal MR images were obtained of 18 fresh TMJ autopsy specimens and compared with the observations in corresponding coronal cryosections. MR imaging correctly delineated the mediolateral position of the disk in 15 joints (83%) and incorrectly delineated it in three joints (17%). Osseous anatomy was correctly assessed in 17 joints (94%). On cryosections, six joints (33%) showed medial disk displacement and two joints (11%) showed lateral displacement. In five of these eight joints the medial or lateral displacement occurred in conjunction with an anterior displacement, that is, rotational displacement. Clinical MR imaging in 37 patients (61 joints with coronal images) showed medial or lateral disk displacement in 16 joints (26%). This study suggests that rotational and sideways displacements of the TMJ disk are an important aspect of internal derangement. The multiplanar capabilities of MR are suitable for an assessment of these abnormalities.

The normal temporomandibular joint (TMJ) was evaluated using magnetic resonance (MR) imaging with a surface coil in five subjects and compared with the abnormal joint in 37 patients (aged 14-59 years; total joints studied, 76). Multisection 3-mm-thick sagittal, coronal, and axial images were obtained with a 1.5-T MR system and 6.5-cm-diameter surface coil using both partial saturation and spin-echo sequences (TR = 1,000 msec, TE = 20 or 25 msec). A comparison with arthrography (n = 13 joints), computed tomography (CT) (n = 11), and surgical (n = 5) findings demonstrated that MR imaging with a surface coil provided an accurate depiction of both normal and abnormal TMJs. MR provided information about meniscal position, morphology, and histology that was not available with either arthrography or CT alone. The imaging potential of MR and its noninvasive characteristics warrant priority for further examination of MR as a useful modality in the diagnosis of TMJ pain and dysfunction.

Computed tomography of the temporomandibular joint has been shown to be an accurate method of assessing the position of the disk. To date, we have examined over 500 patients with this modality and have found it also to be effective in the evaluation of other osseous and soft tissue abnormalities. An overview of temporomandibular joint pathology is presented, including the range of osteoarthritic changes from spur formation to complete fusion. Anterior dislocation, with and without reduction, and closed lock are demonstrated. A heretofore unreported phenomenon—posterior dislocation of the meniscus with open lock—is presented. Also shown is the computed tomography evaluation of splint therapy, which has not been dealt with in other publications.

Discussed is the ability of magnetic resonance imaging, a noninvasive and nonionizing technique, to depict abnormalities of the meniscal position and morphologic structure for patients with joint pain and dysfunction. Magnetic resonance imaging of the temporomandibular joint, using surface coils, a noninvasive, nonionizing technique that improves the ability to depict abnormalities of the meniscal position and morphologic structure for patients with joint pain and dysfunction.

Eighty-two patients with audible clicking were evaluated and treated with splints made by using arthrographic assistance. In the course of this study, it became apparent that the later the opening click, the earlier the closing click. It was not always possible to auscultate or palpate either an opening or a closing click in many patients with arthrographic findings of disk displacement with reduction. Since the opening click was the only audible sound in some patients, clinical judgment alone cannot be used to replace the displaced disk at an optimal mandibular position. The elimination of the opening click does not always signify recapture of the disk. Maxillomandibular and incisal relationships limit the amount of protrusion possible to recapture the displaced disk.

Magnetic resonance (MR) imaging has quickly emerged and already replaced computerized tomography (CT) in the evaluation of cerebellopontine angle (CPA) lesions, although even MR scanning may occasionally yield equivocal results. We recently studied six patients with a new MR image-enhancing contrast, gadolinium-DTPA (Gd-DTPA). All patients were suspected of having CPA pathology, and the standard MR scan was either negative, equivocal, or left unanswered questions regarding confirmed lesions. The Gd-DTPA-enhanced MR scan confirmed tumors or added useful information in five of six patients.

Pluri-directional tomographic and arthrotomographic findings are described in six patients with dislocation of the jaw severe enough to require medical assistance. A grooved defect along the posterior aspect of the condylar head was noted in two of the six patients. The arthrotomographic findings that were obtained in one patient that was dislocated at the time of the arthrogram did not suggest a meniscocondyle incoordination as a mechanism. However, arthrotomographic findings in the six reported cases suggest that significant intra-articular soft tissue damage may result.

Splint therapy for mandibular repositioning is an accepted method of treatment for patients with temporomandibular joint pain and dysfunction. An accurate method of registering the optimal mandibular position on the basis of meniscocondyle relationships depicted on arthrographs is described.

Direct sagittal CT imaging of the TMJ provides several distinct advantages. Most significant is that direct imaging allows noninvasive evaluation of the disk. Direct sagittal CT scanning can confirm a clinical diagnosis of internal derangements as well as monitor splints intended for recapturing of the disk. Furthermore, the CT direct imaging allows excellent views of the bony architecture similar to those obtained with tomography. Used with clinical history and physical examination, CT can provide an excellent diagnostic modality to help provide better care for patients with internal derangement of the TMJ.

Temporomandibular joint dysfunction is a common clinical problem that has been reported to affect 4%-28% of adults. Temporomandibular joint arthrography has shown that many of these patients have intraarticular abnormalities involving the meniscus. A noninvasive test that could demonstrate the meniscus as well as bony abnormalities of the joint would be an important advance. In an attempt to develop such a noninvasive test, we have performed direct sagittal computed tomography (CT) on cadaver temporomandibular joints and have correlated the images with anatomic sections. We are currently applying this technique clinically and report one representative example in which direct sagittal computed tomography of the temporomandibular joint accurately demonstrated an anteriorly displaced meniscus.

We compared patient morbidity associated with temporomandibular joint (TMJ) arthrography using both meglumine/sodium diatrizoate (60%) and the new monoacidic dimer, Hexabrix, in a double-blind randomized clinical trial in 31 patients. Patients experienced maximal discomfort from TMJ arthrography with the initial joint filling and joint distension; this rapidly resolved over 10 minutes. Delayed exacerbation of pain is less than described for shoulder arthrography. The newer contrast media promise to decrease patient morbidity with arthrography.

After repositioning splint therepeutic patients were evaluated for a minimum of 6 mm forty-five (88%) of the patients were considered positive been treated successfully, whereas six (12%) patients as required surgery to correct meniscal displacement. A detailed analysis of signs and symptoms before and after splint treatment is in progress.