The Diagnostic Accuracy of 3D Imaging in Identifying Impacted Third Molars and Their Proximity to the Inferior Alveolar Nerve: A Retrospective Study of Radiographic Features

Zainab A.H. Al-Tamemi; Huda Ashur Shati  Qutbi

doi:10.51699/cajmns.v7i1.3047

Zainab A.H. Al-Tamemi College of Dentistry, University of Wasit, Wasit, Iraq
Huda Ashur Shati Qutbi College of Medicine, University of Wasit, Wasit, Iraq

DOI: https://doi.org/10.51699/cajmns.v7i1.3047

Keywords: Cone-Beam Computed Tomography, Mandibular Third Molar, Inferior Alveolar Nerve, Diagnostic Accuracy, Panoramic Radiography

Abstract

Damage to the inferior alveolar nerve during the extraction of the third molar of the mandibular teeth can lead to an irreversible loss of sensation in up to 7.8%. The two-dimensional nature of panoramic radiography undermines the ability to assess the relationship between nerves and the tooth, whereas the use of CBCT as the routine modality is controversial and is affected by cost demands. To compare the accuracy of CBCT with that of panoramic radiography in the detection of the proximity between mandibular third molars and the inferior alveolar nerve by utilizing findings of surgical intervention as the standard of reference. Retrospective analysis of 320 patients undergoing impacted mandibular third molar extraction. Both imaging modalities were evaluated using standardized criteria with intraoperative findings as gold standard. Diagnostic performance, predictive modeling, and cost-effectiveness were analyzed. CBCT has demonstrated a better diagnostic performance (AUC 0.922) than in the case of panoramic radiography (AUC 0.679). Sensitivity and specificity of direct contact visualization were 88.1 and 91.7% respectively. Panoramic signs showed great false-positive result-mere 45.9% surgical verification of root darkening. The most significant predictor of nerve exposure was an in-direct contact with CBCT (OR: 67.3). There was permanent neurological deficit of 1.9 as opposed to 3.2-7.8 in other studies. The optimal value received on CBCT use was selective where it prevented 58% of complications with a requirement of imaging in 44.7% of the cases. The diagnostic accuracy of nerve-tooth proximity is far superior using CBCT. The new selective CBCT protocols in form of panoramic risk indicators can markedly enhance patient outcomes without compromising affordability, making it possible to support the implementation of the method in the following high-risk cases based on evidence.

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