The effect of two enhancement tools on the assessment of the relationship between third molars and the inferior alveolar canal

Abstract

Objective: This study aims to assess the relationship between the inferior alveolar canal (IAC) and inferior third molars using digital panoramic images (DPI) with and without enhancement and compare the panoramic signs with cone beam computed tomography (CBCT) findings.

Methods: The DPIs and CBCT of 50 patients were analyzed. The DPIs were copied and enhanced using edge enhancement and an invert tool and then analyzed by two observers using the scores: darkening of the root; deflection of the root; narrowing of the root; superimposition of the root; bifurcation of the root over the IAC; diversion of the IAC; interruption of the cortex of the IAC, and no radiographic findings noted. Kappa and exact binominal tests were used to analyze the correlation between DPIs and CBCT images. The intimate relationship scores were evaluated using a t-test and Mann-Whitney test.

Results: The original DPIs, and the edge enhanced and invert tool images produced kappa coefficients of 0.528, 0.528 and 0.551, respectively. There was no difference among the methods evaluated in this study (p = 0.981).

Conclusion: Similar agreement was observed between DPIs with and without enhancement. However, panoramic radiography is not the ideal method to analyze the relationship between lower third molars and the IAC.

Keywords: Mandibular nerve; Panoramic radiography; Third molar; X-ray computed tomography.