Observer performance in assessment of condylar position in temporomandibular joint radiograms

The condylar position at centric occlusion has been considered important in diagnosis of the temporomandibular joint. The present study describes inter- and intra-observer variation in radiographic assessment of condylar position. One radiogram obtained by using an individualized lateral oblique transcranial projection and three corrected sagittal tomograms from the lateral, central, and medial parts of the joint were selected from each of 31 patients. In the resulting 124 radiograms three observers assessed the position of the condyle as posterior, central, or anterior on two occasions, 3 months apart. Concordant reports for all three observers were found in 63%. The interobserver agreement two by two ranged between 69% and 79%, whereas the intraobserver agreement ranged between 81% and 90%. The observer variation and limitations of radiographic techniques should be considered when the therapeutic implication of condylar position is discussed.     

Deterioration of temporary silicone implant in the temporomandibular joint: a clinical and arthroscopic follow-up study

Dacron-reinforced silicone material was used as a temporary disk replacement implant in twenty-seven consecutive patients who underwent diskectomy. Symptoms and the status of the implants were recorded when the implants were removed 1 to 19 months postoperatively (median, 4 months). At the time of removal of the implants, eleven patients showed mechanical dysfunction, which was associated with pain in four patients. All but one of the implants showed wearing facets, and fifteen implants were cracked or perforated. Arthroscopic examination was performed when the implant was removed in the last six patients. This revealed that the extension of the joint compartment corresponded well to the dimension of the implant. Arthroscopy also disclosed that initially even and shiny articular surfaces remained so, articular surfaces in joints with fibrous ankylosis became shiny but uneven, and arthrotic articular surfaces showed no changes. It was concluded that disk-replacement implants can prevent postoperative ingrowth of fibrous tissue and development of intra-articular adhesions and that the implant has the capacity to protect the articular surfaces as long as the material is intact. Since more than half of the implants were cracked or perforated, an implant material with mechanical properties superior to those of Dacron-reinforced silicone would be preferable.     

Common abnormalities in temporomandibular joint imaging

Magnetic resonance imaging has evolved as a prime diagnostic method for soft-tissue abnormalities of the temporomandibular joint. The most common temporomandibular joint abnormalities are internal derangement and osteoarthritis, but there are many other reasons for pain and dysfunction that are often overlooked. The purpose of this paper is to illustrate several of these more unusual and less well-recognized causes for temporomandibular joint pain and dysfunction. For example, internal derangement is often seen in asymptomatic individuals. Another purpose is to illustrate the difference in magnetic resonance imaging of asymptomatic and symptomatic internal derangement.     

Epidermal nevus syndrome: megalencephaly with bihemispheric and cerebellar involvement: imaging and neuropathologic correlation

Epidermal nevus syndrome (ENS) is a sporadic neurocutaneous disorder characterized by the combination of epidermal nevi with significant central nervous system, eye, and skeletal abnormalities. Hemimegalencephaly and related brain abnormalities are the dominant neuropathologic abnormalities in ENS. Magnetic resonance imaging features of the case reported here revealed enlargement of both cerebral hemispheres and malformed basal ganglia, with incomplete separation of the caudate nucleus and putamen. In addition, the right cerebellar hemisphere was enlarged, with disorganized folia. None of these findings have been reported previously in this disorder.     

Diffusion-weighted MR imaging of neuro-Behçet's disease: a case report

We present a serial study of diffusion-weighted imaging (DWI) in a patient with neuro-Behçet's disease. Initial T2-weighted magnetic resonance images showed a hyperintense lesion in the brain stem. The lesion was slightly hyperintense on DWI and the apparent diffusion coefficient (ADC) was slightly increased. Ten months later, DWI showed an improvement in the abnormal signal intensity and the region of increased ADC had increased in size, especially on the left side. DWI is useful for differentiating an acute exacerbation of neuro-Behçet's disease from acute infarction.     

Arthrography of the temporomandibular joint

The TMJ is anatomically and functionally complex. Arthrography has shown that anatomic abnormalities account for many causes of TMJ dysfunction. Arthrography is a valuable tool for understanding TMJ disorders and assisting in the establishment of a rational basis for treatment planning.     

Results of temporomandibular joint diskectomies in Sweden 1965-85

There have been divergent opinions about the prognosis of temporomandibular joint diskectomy. Therefore we have retrospectively evaluated all diskectomies performed in Sweden during the period from 1965 to 1985. Eighty-seven patients had been operated upon with this technique and 69, with a follow-up time of 6 months or longer (median 20 months), were analyzed. The median of maximal opening increased and 74% of the patients had less frequent and less intensive pain at the follow-up examination than before surgery. The overall results of the operations were good in 51% of the patients (none or mild pain and opening greater than or equal to 35 mm and horizontal movements greater than or equal to 5 mm), acceptable in 22% of the patients (none or mild pain and opening greater than or equal to 30 mm) and bad in 28% of the patients (severe pain or opening less than 30 mm). The preoperative pain was found to be more diffuse in the patients with bad postoperative results than in the patients with good and acceptable results. This emphasizes the importance of avoiding operating on patients with sources of pain and functional limitation other than the temporomandibular joint proper. The operation should be used restrictively and only on accurately diagnosed patients with severe pain and functional limitation that originate in the joint and have not been alleviated by adequate nonsurgical treatment. The risk of residual pain or limitation of opening should be included in the preoperative evaluation.     

Anterior repositioning splint in the treatment of temporomandibular joints with reciprocal clicking: comparison with a flat occlusal splint and an untreated control group

The anterior repositioning splint is widely used to treat temporomandibular joints with reciprocal clicking. This treatment was compared to a flat occlusal splint and to an untreated control group. The anterior repositioning splint decreased joint pain at rest, during chewing, and during protrusion. Reciprocal clicking was eliminated and palpatory tenderness of the joint and muscles was reduced. This favorable effect was of short duration. The majority of the patients reported pain and clicking and demonstrated tenderness following removal of the splint after 6 weeks' treatment. The flat occlusal splint decreased joint tenderness but did not affect clicking or muscle tenderness. In the control group the clicking remained and the frequency of muscle tenderness increased. The results indicate that temporomandibular joints with reciprocal clicking can be successfully treated by positioning the mandible anteriorly. Since the symptoms returned when the splint was removed a more permanent change of mandibular position seems necessary.