Efficacy of digital panoramic radiography devices and CBCT in measuring the minimum distance between the floor of maxillary sinus and the alveolar crest (A comparison)

An accurate localization of the lowest border of the cortex of maxillary sinus floor is important to avoid injury in certain surgical procedures. The aim of this study was to evaluate and compare the accuracy of linear measurements between digital panoramic radiography and cone beam computerized tomography (CBCT) in determining the vertical distance between the alveolar crest and floor of the maxillary sinus. In this descriptive study 2 cadaver’s skull were used. Thirteen areas separated by 5mm distance were selected on each skull. A total 26 reference points were marked by gutta percha cones between maxillary first premolar and second molar. Digital panoramic radiography and CBCT were obtained، after which، direct measurements were taken on sectioned skulls using a digital caliper (0. 1mm accuracy). After of adjusting the radiographic values with the magnification factors given for each unit،statistical analysis was done using the Wilcoxon and signed ranks test. The mean error for linear measurements was 0. 36 + 0. 34 mm in digital panoramic radiography and 0. 08 ±0. 06mm in CBCT (P= 0. 001). All (100%) values obtained for CBCT and 65. 38% of values obtained for digital panoramic were within ± 0. 5 mm of error limits. CBCT offers more accurate linear measurements to determine the vertical distance between the alveolar crest and floor of the maxillary