Original Article| Volume 130, ISSUE 6, P625-631, December 2020

Prognosis for the impacted lower third molars: Panoramic reconstruction versus tomographic images

Published:September 25, 2020DOI:


      The aim of this cross-sectional accuracy study was to compare panoramic reconstruction (PR) and multiplanar reconstruction (MPR) images, which are used to establish the prognosis for impacted mandibular third molars in relation to professional decision making.

      Study Design

      Images of 10 patients who had undergone cone beam computed tomography (CBCT) examination were selected, resulting in 2 distinct groups of images, with 10 in each group: PR and MPR. To check prognostic accuracy, 2 images from each group were randomly selected and reinserted into the sample, totaling 24 images. A questionnaire was completed by 54 professionals: 27 orthodontists and 27 oral and maxillofacial surgeons (OMFSs). Data were evaluated by using the χ2 and McNemar's tests and Kappa statistics at P < .05.


      There were no statistically significant differences when isolated PR images were compared with MPR images by orthodontists (P = .72) or OMFSs (P = .45). However, there were significant differences in the professional decision regarding the prognosis for impacted teeth, where OMFSs indicated the need for more extractions compared with orthodontists (P < .0001).


      There are no differences between PR and multiplanar CBCT images with regard to the determination of the prognosis for impacted mandibular third molars. However, there was a difference in the decision making between the different specialties.
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