Abstract

CASTRO, Ricardo Yuki de; BRASILEIRO, Cláudia Borges  and  GIOVANNINI, José Flávio Batista Gabrich. Evaluation of the gray-scale values of glass ionomer cement in indirect digital imaging. Arq. Odontol. [online]. 2012, vol.48, n.2, pp. 62-67. ISSN 1516-0939.

Aim: To compare the radiopacity of four glass ionomer cements by measuring their gray values in digital images obtained through the indirect method. Materials and Methods: Five specimens were prepared at thicknesses of 1, 2, 3, and 4mm of the following materials: Magic Glass® R, Maxxion® R, Vidrion® R, and Chemflex® The samples were separated by brand and thickness, and radiographies were taken following a standardized technique. Three radiographs were performed by thickness for each evaluated material. The images were then digitalized and analyzed using the histogram tool of Adobe Photoshop 8.0 to determine the gray levels. For this, three readings were taken in different areas of each sample prepared for each thickness of each evaluated brand. The values obtained were subsequently subjected to an arithmetic mean, and the results were expressed as mean gray levels for each material thickness. Data were analyzed by ANOVA and Bonferroni assays (p<0.05). Results: All thickness sealers presented statistically significant differences when compared to each other for the same material (p<0.001). In addition, the mean gray levels increased in direct proportion with the thicknesses of the specimens. The mean gray levels found in each sealer, for the same thickness, proved to be different, with statistically significant results (p<0.001). Conclusion: The data revealed that Chemflex® presented the highest mean gray levels and radiopacity of all materials tested.

Keywords : Glass ionomer cements; Radiography dental digital.