Panoramic mandibular index as a radiomorphometric tool: an assessment of precision

Abstract

Objectives: To evaluate the intra-observer repeatability and inter-observer reproducibility of the measurements used in deriving the Panoramic Mandibular Index (PMI).

Methods: Two observers measured 21 dental panoramic radiographs independently of each other, both repeating the measurements after a period of 1 week. The measurements were then evaluated using a number of statistical methods.

Results: All sets of compared measurements, both within and between observers, demonstrated significant positive correlations, with no significant difference between measurements Precision, however, was poor and variable.

Conclusion: The main difficulties in obtaining consistency in repeated measurements were related to individual morphology and radiodensity. In order to improve the validity of the PMI as a measure of local bone loss, repeatability of the measurements should be improved. Suggestions as to how this, might be achieved are discussed.