Comparison of panoramic radiography and CBCT to identify maxillary posterior roots invading the maxillary sinus.

Objectives: Given the limitations of panoramic radiography for assessing topographic relationship of maxillary teeth with sinus floor, the purpose of this study was to assess signs on panoramic radiography that could predict root protrusion into the sinus.

Methods: A total of 46 individuals (330 maxillary posterior teeth) who underwent panoramic radiography and CBCT were enrolled. The relationship between the posterior teeth and the maxillary sinus and panoramic radiography signs (projection of the root apices, interruption of the maxillary sinus floor, lamina dura, darkening in the root apices, and superiorly curving sinus floor enveloping the associated tooth root) associated with protrusion of root apices into the sinus were evaluated.