A New Technique for Radiopacity Evaluation of Resin Cements

The aim of the present study was the comparison of radiopacity of different resin cement types using direct digital radiography by calibrating the calculations on the radiogram according to the dead pixel value on the phosphor plate for the first time in literature. The radiopacities of currently used ten different resin cements(G-CEM, I-CEM, Choice 2, Duo Link, TheraCem, eCEMENT DC, MaxCem Elite Chroma, BisCem, NX3, and Maxcem Elite), enamel and dentin were compared with the densitometer. The digital radiographs were acquired and Image J software was used to convert the images into numerical data for analysis. After the dead pixel calibration, the equivalent aluminum thickness value of each sample was calculated by the correlation analysis method. According to test results, although there was no significant difference between G-CEM and I-CEM, all the materials, enamel and dentin had a significant difference from each other. MaxCem Elite had the highest radiopacity while G-CEM had the lowest. eCEMENT DC, MaxCem Elite Chroma, BisCem, NX3, and Maxcem Elite had higher radiopacity than dentin. Those with lower radiopacity than dentin (G-CEM, I-CEM, Choice 2, Duo Link, and TheraCem) should be carefully used in both subgingival located or radiolucent restorations and implant-supported prostheses. Dead pixel calibration enables materials to be evaluated more accurately and this method will also make it possible for the first time in literature to compare the same samples with each other on different phosphor plates.