Assessment of reliability of cineradiographic recording of temporomandibular joint movements

As part of a cineradiographic study of temporomandibular joint movements, the reliability of the apparatus and techniques has been assessed. The areas of concern were the radiographic procedure, tracing apparatus and tracing technique. To assess the accuracy of the radiographic procedure, anatomical and radiographic measurements of mandibular condyles were compared. A range of variation of 0-46--0-8 mm was found, which compared favourably to the only previously published investigation. The use of mechanical devices simulating the fundamentals of mandibular movements suggested that the cineradiographic record showed paths of opening and closing separated more widely than occurred in vivo. The reliability of the tracing apparatus was assessed by calculated misalignments and found to be acceptable. The subjective error in tracing cineradiographic films by a regular observer was investigated by a point location error method. The error was found to be small and within acceptable limits.

Routine tomography of the temporomandibular joint

Routine lateral tomography of the temporomandibular joint has resulted in a three-fold increase in the detection of positive findings. The technique is easily accomplished, eliminates the problem of superimposition of unwanted structures, permits a true lateral view of the condyle and condylar fossa, and allows small articular surface abnormalities to be identified. Although the entrance skin dose to the patient's face in the beam is about two times greater per exposure than that for our previous conventional open and closed lateral views, we believe that the increased dose is reasonable and the resulting improved diagnostic accuracy outweighs this disadvantage.

[The value of Schüller's temporomandibular joint radiography for the diagnosis of joint related malocclusion]

A tentative diagnosis of the supposed position of the condyle in its glenoid fossa was made for 150 temporomandibular joints only be means of Schuller radiographs. To determine the value of the radiographs for diagnosis of occlusion the radiologic diagnosis of each joint was then compared with the real diagnosis based upon instrumental functional analysis of the occlusion, clinical findings and individually projected radiographs of the joint. Radiologic diagnosis and real diagnosis coincided to a relatively high degree provided that the radiographs were readable. Very high correspondence was found for anterior and posterior displacement of the condyle whereas supperior, inferior and lateral displacement showed considerably less coincidence. By the Schuller technique 30 of the 150 joints were not represented readably and better projection by a different angulation of the central X-ray beam was possible for half of those only. Posterior displacement of the condyle was found to be the most frequent malposition of the joint in this study.

Radiographic changes in the temporomandibular joint subsequent to vertical ramus osteotomy

The position of the mandibular condyle in patients treated for mandibular protrusion by the oblique vertical osteotomy of the mandibular rami was studied on temporomandibular joint radiographs exposed according to the oblique transcranial projection. Forty-four adults participated in the study, and the radiographs were taken before the operation, 6 weeks postoperatively and 1 year postoperatively. At the 6-week postoperative control all the variables measured indicated a significant downward and forward displacement of the condylar fragment of about 1mm. The changes did not increase the variability of the joint morphology. At the 1-year postoperative control there were still significant differences in the position of the condyle compared with the pretreatment recording. A slight tendency to normalization was, however, observed. The mobility of the condyle, which was greatly restricted at the 6-week postoperative control, was fully restituted 1 year after the operation.

[The diagnosis of condylar process fractures]

The detection of condylar process fractures by clinical examination and the interpretation of radiographs belong to the stomatologist's diagnostic tasks. On the contrary, the exact location of the fracture lines and the recognition of the types of proximal fragment displacement often present problems. Diagnostic errors may also occur, mainly resulting from radiological illusions. The comprehensive evaluation of the data from 3027 patients with injuries of the facial bones, involving 1050 condylar process fractures, and the verification of the relevant radiological findings permitted to determine the location of the fracture lines and the types of fragment displacement, to recognize misinterpretations and to give suggestions for establishing a definite diagnosis.

[Selective tomography in the study of the temporo-mandibular joint. (author's transl)]

The majority of temporo-mandibular pains and dysfunction can be related directly or indirectly to the occlusal relationship of the teeth. The first manifestation is a slight reduction of the interarticular space, that must be early diagnosed, to prevent organic changes. Tomography is the one technique able to give a exact information of temporo-mandibular joint. But if we ask to that examination to detect very slight change of the interarticular space, the technique must be accurate and established in function of morphology of the patient; we have observed great variations in direction of the axis of condyles from one person to the other, and even from one side to the other for the same subject. So that, the first stage of the roentgen examination will be a radiograph taken in submentovertical (Hirtz) position. We measure the angle formed by the axis of each condyle and the sagittal median plane. The maim beam wil be directed in the axis of the condyle for sagittal tomography and perpendicularly for frontal tomography. It is important to state precisely that for tomography "closed mouth", the patient must be in terminal occlusion during the whole examination. For tomography "open mouth" we place a wedge between dental arches.

Condylotomy. A clinical and experimental appraisal of a surgical technique

211 cases of temporomandibular joint pain/dysfunction syndrome treated by condylotomy were traced. 172 operations were investigated by questionnaire and 119 patients examined clinically and radiographically. Operated patients constituted less than 3% of all patients with the syndrome. 91% were cured or improved by surgery. The anatomical structure involved in the technique and operative complications, are discussed. Principal effects of surgery were to produce an increase in radiographic joint space and shortening of the ramus with minimal long term change in the position of the condylar head from its postoperative position. The clinical findings as regards remodelling were confirmed and investigated histologically in a primate model. The mechanisms of pain production in the temporomandibular joint pain/dysfunction syndrome are discussed.

Anterior condylar displacement: its diagnosis and treatment

A deflective slide in centric relation to centric occlusion does not necessarily mean anterior condylar displacement. Its diagnosis and treatment depend on the correlation of three factors: the direction and magnitude of the mandibular slide from centric relation to centric occlusion, the change in vertical dimension of occlusion during the slide, and the position of the condyles in the fossae when the teeth are in the maximum occlusion (centric occlusion). When the change in vertical dimension almost equals to amount of slide from the deflective contact in centric relation to maximum intercuspation, very little anterior condylar displacement would be expected. Conversely, with proportionately little change in vertical dimension, more anterior condylar translation is required for a given degree of anterior slide. Examples of each type of anterior slide were related to the TMJ radiographs of the condylar position. If the direction and magnitude of the deflective occlusal contact can be correlated with the TMJ radiographs, the centric relation is ""functional,'' and the clinically retruded mandibular position should be used. When this correlation does not exist, the centric relation is ""dysfunctional'' and the terminal hinge position (retruded mandibular position) should not be used for restorative or corrective procedures. Examples of anterior condylar displacement were given, including deviation, with a comparison of ""before'' and ""after'' TMJ radiographs.

Odontogenic myxoma. A clinical and ultrastructural study

The odontogenic myxoma is an uncommon neoplasm of the jaws that is believed to arise from the primitive, mesenchymal portion of the tooth germ. This study surveys nine cases of odontogenic myxoma of the jaws. Analysis of the clinical material revealed that the myxoma occurred most frequently in the posterior regions of the mandible and will recur if initial therapy is too conservative. The average age of the patients in this series was 26.5 years. Five cases involved females and four involved males. Electron microscope findings revealed that the tumor cells are probably responsible for the secretion of the myxomatous intercellular material of the neoplasm.

Radiologic examination of trismus as a complication of cancrum oris

In the radiologic examination of trismus complicating cancrum oris, abnormalities can be detected in the soft tissues, osseous tissues, and temporomandibular joint. In the soft tissue, scar formation may show as a depression in the normal smooth, convex contour of the lateral aspect of the face. There may be a myositis ossificans in the soft tissue, producing bony bars that lead to extra-articular ankylosis. By far the most important changes are in the temporomandibular joint, where there can be varying degrees of joint narrowing, sclerosis of the articular cortex, flattening of the mandibular condyle and occasionally also of the eminentia articularis, osteophytosis, and intra-articular bony ankylosis. Hypoplasia may involve the entire hemimandible or be restricted to its condyloid process. The latter may lead to compensatory enlongation and hypertrophy of the coronoid process. Bony ankylosis of the coronoid process to the posterior wall of the maxilla was seen in three cases. The pathogenesis of these changes is discussed.

Screening in a dental clinic for adult rheumatoid arthritis involving the temporomandibular joint using a statistical discriminant function

The radiological features seen on the temporomandibular joint radiographs of ninety-nine cases of adult rheumatoid arthritis were used to distinguish this group from a group of eighty-three control subjects using the method of logistic discrimination. A readily calculable diagnostic score, whose value was verified by a second study involving thirty-two patients, sixteen of whom suffered from adult rheumatoid arthritis, was estimated. This second study was further used to illustrate how this scoring system would be modified to take account of extra information. Although a long term evaluation of the method is envisaged its clinical application is indicated and its practical value demonstrated.

Treatment of temporomandibular joint ankylosis with methyl methacrylate interpositional arthroplasty: reprot of four cases

Four cases of interpositional TMJ anthroplasty are presented. All patients had been operated on previously. The initial success was compromised by reunion of the proximal and distal surgical sites. These failures were due to inadequate gap arthroplasty; lack of complete coverage of the superior distal stump; or lack of retention of the alloplast at the site of placement. The case of manipulation and good tissue tolerance of methyl methracrylate make it an excellent material for interpositional arthroplasty.

Long-term results of functional treatment of condylar fractures with the long bridle according to A. Rehrmann

Long-term results in 23 cases with condylar fractures are presented. The method of treatment consisted in forward extension of the mandible by means of a long rubber bridle stretched between a steel hook at the chin and a strong sagittal wave-like, bent wire incorporated in a head cap. Strength and direction of the bridle can be modified. It provieds perfect repositioning of the mandible and a normal occlusion within some hours. The idea of this functional method is to eliminate the displacing muscular pull and dorsally-directed deviation of the mandible, and to restore muscular balance even with full range of mouth-opening. The distraction of the mandible from the glenoid fossa creates space and enables the dislocated condyles to upright themselves spontaneously. In cases of intracapsular or subcondylar fracture the active movements of the mandible, under the conditions of equilibrium, lead to a remodelling of the damaged condylar heads to a new form, induced by function. Ankylosis is avoided with certainty. Mandibular splinting or osteosynthesis are needed only in concomitant fractures of the rest of the mandible. The temporo-mandibular joint area and the rest of the mandible are considered to be independant entities in the treatment of condylar fractures. The method described is simple. Full mandibular mobility was obtained in all cases and spontaneous uprighting of dislocated condyles observed. There was no need for subsequent opening exercises.

Osteocartilaginous exostosis of the mandibular condyle. Case report

Osteochondroma of the mandibular condyle is extremely rare. An unusual case of a 32-year-old man is reported. Throughout a two-year period the patient suffered from intractable pain in the left T. M. J. region, anterior dislocation of the condylar head, malocclusion and facial asymmetry. Radiologic examination revealed that the cartilaginous cap of an overgrowth had functioned as an articular cartilage. A "pseudo articulation" was created with the prominent articular eminence and allowed an almost free movement of the mandible. Review of the seven reported cases revealed that the rare occurrence, natural history, clinical course and lack of recurrence of osteochondroma of the condylar process all substantiate the contention that this overgrowth must be considered as an osteocartilaginous exostosis rather than a neoplasm.

Temporomandibular joint arthroplasty with fascia lata

Two patients with temporomandibular joint arthralgia and ankylosis were managed with arthroplasty and insertion of fascia lata. The role of physiotherapy, chances of facial nerve damage, role of steroids, and advantages of fascia lata are discussed.