Radiographic detection of overhangs formed by resin composite luting agents.
OBJECTIVE
An in vitro model was used to assess the ability of standard radiographic techniques to detect marginal overhangs of resin composite luting agents beside porcelain and resin composite inlays.


METHODS
The radiodensity of five commercially available luting resins was determined using ISO 4049 methodology. For four of the luting agents, artificial overhangs (0.5 x 0.5 x 2 mm) were created at the cervical margin of standard resin composite and porcelain inlays. Radiographs were recorded, using wax as a tissue equivalent, and the overhangs reduced incrementally in depth by 0.5 mm with serial images at each depth. The images were assessed in random sequence by three observers.


RESULTS
There were significant differences between the radiopacity of the luting resins. These correlated well with the ability of the observers to detect marginal overhangs adjacent to resin composite inlays.


CONCLUSIONS
Even with the most radiopaque luting material, a substantial marginal ledge could not be detected in association with a radiopaque resin composite inlay. The threshold for detection of the overhang was lower when using a radiolucent porcelain inlay.
Department of Restorative Dentistry, Dental School, University of Newcastle upon Tyne, UK.
B
B
O'Rourke
A W
AW
Walls
R W
RW
Wassell
D000704:Analysis of Variance; D001641:Bicuspid / Q000000981:diagnostic imaging; D003188:Composite Resins / Q000737:chemistry; D003287:Contrast Media; D003738:Dental Cements / Q000737:chemistry; D003776:Dental Porcelain / Q000737:chemistry; D003793:Dental Restoration, Permanent; D006801:Humans; D007284:Inlays; D015588:Observer Variation; D011861:Radiography, Dental; D013499:Surface Properties
D003188:Composite Resins; D003287:Contrast Media; D003738:Dental Cements; D003776:Dental Porcelain