Prospective comparison of axial computed tomography and standard and panoramic radiographs in the diagnosis of mandibular fractures.

Objective data comparing sensitivity and accuracy between traditional and computed imaging techniques used for diagnosing mandibular fractures is sparse. To address the paucity of information the authors studied prospectively 33 mandibular fractures in 21 consecutive patients with standard mandibular series, panoramic tomography, axial computed tomography (CT), and coronal CT. Differences in diagnostic accuracy and sensitivity as compiled by four blinded reviewers were calculated. Although overall sensitivities of mandibular fracture detection were not statistically significant between the imaging studies, a distinction between the four methods did exist. Coronal CT was the most accurate imaging method, followed by mandibular series, panoramic topography, and axial CT. Excluding technically inadequate studies, panoramic tomography was 100% accurate and sensitive. Diagnostic accuracy and sensitivity did not correlate measurably with reviewers' impressions of the quality of a particular exam. Axial CT detected significantly fewer angle fractures than standard radiographs (60% vs. 98%, p = 0.006) and coronal CT (60% vs. 100%, p = 0.008). False-positives were unusual except for plain mandibular radiographs. The clear definition of both coronal and axial CT scans made their analysis simpler than the plain radiographs. Lack of fracture displacement was the single most important factor in missed fractures with all modalities. Despite reviewer concerns about the quality of the plain mandibular series, the high accuracy and sensitivity of this imaging technique and applicability in all patients, coupled with its low cost, make it an excellent screening exam for all patients with suspected mandibular fractures. In clinically stable and cooperative patients with mandibular trauma, panoramic radiography and coronal CT are recommended to confirm clinical suspicions when the mandibular series is equivocal. To supplement the mandibular series in the uncooperative or multisystem trauma patient, axial CT scans have not been beneficial. These diagnostic modalities do not obviate the need for a careful physical exam.