Detailed tomography of periapical and periodontal lesions. Diagnostic accuracy compared with periapical radiography.

Objective: To compare the diagnostic accuracy of detailed tomography using the Scanora system with that of conventional periapical radiography for detecting periapical and periodontal lesions.

Methods: We selected for comparison 243 periapical and 322 periodontal sites in 177 patients. Five observers independently assessed radiographs for the presence or absence of the following lesions: periapical bone changes, widening of apical and marginal ligament space, crestal erosion, vertical bone loss, furcation involvement and calculus.

Results: ROC analysis demonstrated no significant differences in the overall interpretation of either disease. Periapical radiography was superior (p < 0.05) to tomography for the detection of calculus. The sensitivity of tomography for periapical pathology was 87%, and 70% for periapical radiography. Sensitivities for periodontal diseases were 84% and 77%. Specificities were 81%, 90%, 77% and 79%, respectively. Differences for sensitivity and specificity were significant (p < 0.05) in relation to periapical pathology. The energy imparted during tomography was 0.92 mJ.

Conclusion: Detailed tomography and periapical radiography performed equally well for the overall diagnosis of periapical and periodontal lesions. Tomograms differed substantially from periapical radiographs in both sensitivity and specificity for detecting periapical lesions in posterior regions. The energy imparted during detailed tomography is similar to that from two D-speed films.