The accuracy of dental panoramic tomographs in determining the root morphology of mandibular third molar teeth before surgery

Objective. The objective of this study was to assess the accuracy of dental panoramic tomograph (DPT) in the presurgical assessment of mandibular third molar teeth by correlating the radiologic interpretation with surgical findings. Study design. DPTs of 300 mandibular third molar teeth were assessed by 9 staff oral surgeons for root morphology and proximity to the inferior alveolar neurovascular bundle. Detailed records were made at surgery. Results. The sensitivity and specificity for observation of root curvatures (+/-15%) were 29% and 94%, respectively. The sensitivity and specificity of determining an intimate relationship between the root and the neurovascular bundle were 66% and 74%, respectively. Kappa analysis demonstrated poor levels of agreement between radiologic interpretation and surgical findings when the number of roots was determined (0.191) and also when the roots were fused or separate (0.466). Conclusion. Using DPTs to assess mandibular third molar teeth before surgery gives poor diagnostic accuracy of anatomic form and structures.