The effect of storage time on the degree of dye leakage of root-end filling materials.

The quality of the apical seal obtained by root-end filling materials generally has been assessed by the extent of dye penetration. Most investigators have allowed the root-end filling materials to set before they are tested. The purpose of this study was to evaluate if storage time had any influence on the amount of dye leakage. Seventy extracted single rooted human anterior teeth were used. After removal of their anatomical crowns, the roots were instrumented, filled with gutta-percha and Roth's sealer, and subjected to test conditions. The roots were coated with two coats of nail polish. Root ends were resected and class I cavities prepared. Sixty class I root-end cavities were filled with with either amalgam, super EBA, or IRM (20 each). Ten roots in each group were placed immediately into India ink for 48 h, the other 10 were stored for 24 h before placement into the ink. Ten roots (five per group) were used as positive (gutta-percha, no sealer) and negative (bone wax) controls. The roots were then demineralized, linear dye leakage was measured, and the data were evaluated statistically using ANOVA. Super EBA, and IRM showed significantly less dye leakage than amalgam (P < 0.0001). No significant difference existed between Super EBA and IRM. Storage time had no significant influence on the amount of dye leakage observed in this study.

Dye leakage of four root end filling materials: effects of blood contamination.

The purpose of this study was to compare the amount of dye leakage (in the presence versus absence of blood) in root end cavities filled with amalgam, Super EBA, IRM, and a mineral trioxide aggregate. After removing the anatomical crowns of 90 extracted human teeth, their roots were instrumented and obturated. Except for their apical 2 mm, the root surfaces were sealed with nail polish. After removal of the apical 2 to 3 mm of each root, a standardized root end cavity was prepared. Five root ends were filled with gutta-percha and no sealer, and another five root ends were filled with sticky wax. These served as positive and negative controls, respectively. The remaining 80 roots were divided into four equal groups and filled with the test materials. For each material, half of the root end cavities were dried prior to placing the filling material. The remaining half were filled after they were contaminated with blood. All 90 roots were then immediately placed in 1% methylene blue dye for 72 h. Finally, the roots were split and linear dye penetration was measured and statistically analyzed (analysis of variance). Presence or absence of blood had no significant effect on the amount of dye leakage. However, the results showed that there was a significant leakage difference between the root end filling materials (p < 0.0001). Mineral trioxide aggregate leaked significantly less than other materials tested with or without blood contamination of the root end cavities.