Displaced premolars in panoramic radiography: fact or fallacy?
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Updated: Jul 7, 2026
Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Nasila Nohadani1, Yango Pohl, Sabine Ruf
1Department of Orthodontics, University of Berne, Berne, Switzerland.
Objective:
To test the null hypothesis that there is no difference between premolar position visualized on panoramic radiographs (PRs) and lateral headfilms (LHs).
Materials And Methods:
The prevalence of differences in the direction of crown angulation between PR and LH was assessed. Furthermore, brass wire markers with different sagittal and transverse angulations were placed in a dry skull. With the markers in place, LHs and PRs were taken.
Results:
A difference in the direction of crown angulation of unerupted second premolars between PR and LH occurred in 19.5% of patients. The reason for the angulation differences is a buccolingual orientation of the tooth, which appears as a mesiodistal angulation on the PR.
Conclusion:
The null hypothesis was rejected since in one-fifth of the patients premolar projection differs between the panoramic radiograph and the lateral headfilm.
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