RADIOGRAPHIC DETECTION OF OVERHANGS FORMED BY RESIN COMPOSITE LUTING AGENTS

Objectives: An in vitro model was used to assess the ability of standa rd radiographic techniques to detect marginal overhangs of resin compo site luting agents beside porcelain and resin composite inlays. Method s: The radiodensity of five commercially available luting resins was d etermined using ISO 4049 methodology, For four of the luting agents, a rtificial overhangs (0.5 x 0.5 x 2 mm) were created at the cervical ma rgin of standard resin composite and porcelain inlays. Radiographs wer e recorded, using wax as a tissue equivalent, and the overhangs reduce d incrementally in depth by 0.5 mm with serial images at each depth. T he images were assessed in random sequence by three observers. Results : There were significant differences between the radiopacity of the lu ting resins. These correlated well with the ability of the observers t o detect marginal overhangs adjacent to resin composite inlays. Conclu sions: Even with the most radiopaque luting material, a substantial ma rginal ledge could not be detected in association with a radiopaque re sin composite inlay. The threshold for detection of the overhang was l ower when using a radiolucent porcelain inlay.