Evaluation of the radiopacity of a MTA-based root-canal filling material using digital radiography

Abstract

Objective:  The aim of this study was to assess the radiopacity of a relatively new mineral trioxide aggregate (MTA)-based root-canal filling material and to compare it with four currently used root-canal filling materials using a digital imaging system. Methods:  The root-canal filling materials tested were MTA Fillapex, Adseal, AH Plus, Endomethasone and gutta-percha cones. Standard disks of five different root-canal filling materials were exposed together with an aluminum stepwedge calibrated in millimeters. For the radiographic exposures, a storage phosphor plate (size 4; 5.7x7.6 cm) and an x-ray machine at 70 kVp and 8 mA were used. The object-to-focus distance was 30 cm, and the exposure time was 0.2 sec. The grey values of the test materials were measured digitally using the system’s own software and compared with the stepwedge to find the equivalent thickness of aluminum. The data were analyzed statistically with significance levels set at p<0.05. Results:  The radiopacity values of the studied materials in decreasing order, expressed in millimeters of aluminum equivalent, were: AH Plus (9.70), gutta-percha (6.82), MTA Fillapex (5.30), Adseal (3.71) and Endomethasone (3.67). Statistically significant differences were found between mean radiographic density values of the tested materials (p<0.005), AH Plus showing the highest value. Conclusion:  MTA Fillapex was the third most radiopaque root-canal filling material among the tested materials in the study. All of the materials evaluated met the minimum radiopacity standard recommended by International Organization for Standardization and the American National Standards Institute/American Dental Association. Key words:  Aluminum stepwedge, digital radiography, radiopacity, root-canal filling material