COMPARISON BETWEEN CBCT AND PANORAMIC RADIOGRAPHIC IN ALLOCATION WITH THIRD MOLAR IMPACTION NEAR THE INFERIOR ALVEOLAR NERVE: A RETROSPECTIVE RESEARCH

Abstract

Objectives: This study aimed to correlate the diagnostic efficacy of cone-beam computed tomography (CBCT) and panoramic radiography (PR) in determining the relationship between impacted mandibular third molars (IMTMs) and the inferior alveolar nerve (IAN) canal using the Fryback and Thornbury hierarchical model.

Materials and Methods: This retrospective study entered 210 patients (210 IMTMs) who underwent both CBCT and PR imaging preoperatively. CBCT and PR images were checked independently by two experienced radiologists. Radiographic parameters assessed included Winter's classification, Pell and Gregory's classification, radiographic signs on PR, and CBCT findings. The diagnostic efficacy was compared using the Fryback and Thornbury model.

Results: CBCT scored significantly higher than PR for technical efficacy (mean scores: 2.97 vs. 1.97, p<0.001), diagnostic accuracy (2.83 vs. 2.49, p<0.001), and diagnostic thinking efficacy (2.70 vs. 2.28, p<0.001). Darkening of roots on PR was strongly linked with loss of cortication on CBCT (p<0.001). Interruption of the white line and narrowing of roots on PR were typically associated with cortication loss (p<0.001). Loss of cortication was most frequent when the IAN canal was interradicular or buccal to IMTM roots. CBCT total scores were significantly higher than PR (8.51 vs. 6.73, p<0.001).

Conclusion: CBCT exhibited higher diagnostic efficacy than PR in assessing the IMTM-IAN relationship across all levels of the Fryback and Thornbury model. CBCT provided valuable insights for surgical planning and minimizing iatrogenic nerve injuries in high-risk cases.