Accuracy of the Third Molar Eruption Predictor in predicting eruption.

Objective: To evaluate the possibility of applying the Third Molar Eruption Predictor to all panoramic radiographs.
Study Design: Panoramic radiographs were retrospectively analyzed from a 4-year follow-up study of third molars carried out at the University of Copenhagen, Denmark. The radiographs, taken at a mean age of 20.6 years, included 45 unerupted or partially erupted mandibular third molars in 28 subjects. Because the device was calibrated both with simple proportions and by use of the methods of Bayes' Decision Theory, the separation point of the device was therefore adjusted at 12 mm from the distal surface of the second molar.
Results: The predictions of future eruption or impaction made with the calibrated device and the actual clinical outcome 4 years later were in conformity for 80% of the mandibular third molars.
Conclusion: The Third Molar Eruption Predictor may be applied to all panoramic radiographs, but it seems to require calibration before use.