Quantifying condylar distortion in panoramic radiography

Objective

To quantify the amount of distortion of the mandibular condyle in panoramic radiographs when comparing standard and temporomandibular joint (TMJ) programs and different patient positions.

Study Design

Five dry cadaveric mandibles were scanned using standard panoramic and TMJ modes. Markers were placed on the medial (M), lateral (L), anterior (A), posterior (P), and superior (S) aspects of the condyles. The mandibles were imaged with the AT ProVecta 3D Prime in an ideal position, right and left turn as well as chin-up and chin-down. A cone beam computed tomography scan of each mandible was taken to establish true relationships between the markers. Reproducibility was tested by reacquiring the images of one mandible and re-measuring the markers of another.

Results

Distortion was present in all images, regardless of the program and the position of the mandible. Distortion was greatest between the medial and lateral poles in the vertical dimension. Most differences between panoramic and TMJ modes were not statistically significant. Reproducibility of the method was high.

Conclusion

The AT ProVecta 3D Prime produces distortion of the condyle that impacts the radiographic appearance in panoramic radiographs. The TMJ program did not meaningfully mitigate the distortion seen with the standard panoramic program.