Frequency of Recommending Cone Beam Computed Tomography in Comparison to Panoramic Radiograph, While Diagnosing a Pathology/Status of Vital Structures Around Mandibular Impacted Third Molar

Abstract

Objective: This study assesses the quantity and quality of reliability of both conventional and cone-beam computed tomography (CBCT) in evaluating external root resorption (ERR) and proximity of inferior alveolar canal (IAC) around impacted mandibular third molars and also the practicability to advise CBCT as the first radiographic examination in every patient with above pathology. Methodology: A prospective cross-sectional study was conducted with a sample of 73 individuals, aged between 18 and 40 years, irrespective of their sex. Digital panoramic radiograph (PAN) and CBCT were carried out for individuals with mandibular impacted third molars, which were evaluated by three observers independently for ERR and relation of impacted teeth with inferior alveolar nerve (IAN) canal (resorption of IAN cortical plate, impingement, and approximation). The data was analyzed by Kappa test and the PAN and CBCT findings were compared using Wilcoxon signed-rank test. Results: Out of 73 subjects, 13 subjects showed resorption of the IAN cortical plate in CBCT, among which only five were confirmed in PAN. Forty-three cases showed impingement of the third molar on the IAN in PAN, which was completely absent in CBCT. Among 14 subjects who presented contact or approximation of the third molar with the canal in PAN, only seven were confirmed in CBCT. Twenty-five cases actually showed ERR in CBCT, whereas PAN confirmed only eight cases. Pathologies seen on PAN were considerably very less in comparison with CBCT. Conclusion: Thus, we conclude that two-dimensional (2D) radiographs are the first choice of diagnostic radiographs, even though the CBCT is accurate in displaying the pathology; however, the decision to advise CBCT image should depend on whether the information from CBCT changes the surgeon's diagnosis and treatment planning.