The validity of transcranial radiography in diagnosing TMJ anterior disk displacement.

Two transcranial radiographic methods for determining anterior disk displacement in the TMJ were evaluated in comparison with results obtained from arthrography. Both transcranial radiographic methods could only accurately predict the presence of an anteriorly displaced disk in a range of 26% to 56% of the time (for example, the methods gave false-negative results 44% to 74% of the time). The methods were more valuable in correctly identifying joints that were free of disease, achieving this identification anywhere from 64% to 96% of the time. Although noninvasive, these two transcranial radiographic techniques produced results that lacked validity and, therefore, remain of questionable value to the clinician who is diagnosing anterior disk displacement.