Vertical measurements of the Orthopantomograms of 152 patients were made for condylar and rami heights. The symmetry between the right (R) and the left (L) side was calculated with the formula: [(R-L)/(R + L)]. A statistically significant difference between the patients of a routine dental group and the patients treated for craniomandibular disorders was found regarding condylar height symmetry.

As an orthopantomogram provides bilateral information, it seems to be an efficient tool for screening for arthropathy of craniomandibular disorders. An experimental model was designed and constructed to resemble a human mandible. By changing the position of the model in the horizontal plane of the orthopantomograph, nine different images were analysed for changes of vertical magnifications. Emphasis was put on large parts of the mandible like the condyle. In positions that had been altered less than 10 mm from the originally centred position of the mandible in the orthopantomograph, vertical differences between the left and right sides were less than 6%. Observed condylar asymmetries within a 6% difference might, therefore, be due to technical failures.

A comparison between clinical, tomographical, and dental panoramic radiographical findings was made in thirty-one female patients suffering from craniomandibular disorders (CMD). In general it was found that condylar sclerosis was more common in these patients than in earlier studies. After clinical separation of the material into two groups based upon the origin of pain, myogenous versus arthrogenous, no radiographical confirmation of the differential diagnostics could be made. Regarding vertical condylar asymmetry measured on the Orthopantomogram, it was found that 74% of the patients with CMD had more than the 3% of asymmetry regarded as within normal limits. It seems that with an increasing severity of the disorder the level of condylar asymmetry appears less. If the interpretation of the findings is correct its conclusion might lead to the recognition of a morphological factor which could contribute to the development of a craniomandibular disorder.

A comparison has been made between clinical and radiographical findings in a study of eighty-nine patients suffering from craniomandibular disorders. In general it was found that condylar changes were more common in these patients than in earlier studies concerning the severe problems of craniomandibular disorders. A statistically significant correlation between clinical and radiographical findings was found for crepitation with osteophyte formation of the condyle (P less than 0.01). After clinical separation of the patients into two groups based upon the origin of pain, myogenous versus arthrogenous, no radiographical correlation could be made except for condylar osteophytes. With the clinical method used for separation of patients it was found that the clicking of the temporomandibular joint (TMJ) was more common among myogenous patients (P less than 0.05); crepitation was more common among arthrogenous patients (P less than 0.01), as was limited mouth opening (P less than 0.05) and deviation on opening (P less than 0.05). Radiographically, the only statistical difference between the two groups was found for osteophyte formation of the condyle, this was more common among arthrogenous patients (P less than 0.05). As the clinical method has been tested earlier, the results of this study lends support to the idea that conventional radiographical examination is of limited use in the initial diagnostics of craniomandibular disorders. Therefore new alternatives have to be developed.