Does the Winter or Pell and Gregory Classification System Indicate the Apical Position of Impacted Mandibular Third Molars?

Purpose: The present study investigated the relationship of impacted mandibular third molars to the cortical plates and inferior alveolar canal (IAC) using cone-beam computed tomography (CBCT).

Materials And Methods: The present study included CBCT images of 386 lower third molars in 226 patients, for whom the initial panoramic radiographs had revealed a close relationship between the third molars and IAC. The coronal images were prepared to determine the position of apex about the buccal and lingual cortexes and IAC.