Abstract
BACKGROUND AND OBJECTIVES: The proper assessment of the relation between the roots of the maxillary posterior teeth and the maxillary sinus floor represents a real concern for dental practitioners when conducting any procedure in the involved region. Many imaging techniques have been employed to assess this relation. This study aimed to (1) compare the accuracy of digital periapical radiographs with that of cone-beam computed tomography images in assessing the relationship between the maxillary molar roots and the maxillary sinus floor and (2) determine periapical radiographic features (if present) that could indicate the actual protrusion of roots into the sinus cavity. MATERIALS AND METHODS: This observational analytical in vivo study was carried out on 23 Egyptian patients. Cone-beam computed tomography and digital periapical images were obtained for each patient and assessed by three oral radiologists. Results were statistically analyzed in terms of accuracy, specificity, and sensitivity in addition to the McNemar-Bowker and Fleiss's Kappa test. RESULTS: Despite the presence of a significant difference between the results of both techniques, periapical radiography demonstrated 73% accuracy in displaying the sinus-root relation. Moreover, the continuity of the lamina dura suggests (with more than 70% accuracy) that the root is located outside the sinus and vice versa. CONCLUSION: The digital periapical technique is considered an accurate method of assessing the sinus-root relation especially when the root is located outside the sinus. One of the most indictive periapical features of root intrusion into the maxillary sinus is the discontinuity of the lamina dura.