Dye extraction results on bacterial leakproof root fillings

This study was designed to assess and compare the sensitivity and sealability results between bacterial leakage and dye extraction. Eighty mandibular incisors were prepared, and their roots were filled as follows (n = 20): G1, lateral condensation; G2, System B; and G3, Thermafil system. All teeth were mounted in a 2-chamber apparatus, and the coronal access was exposed to human saliva for 100 days. The remaining bacterial leakproof specimens were randomly assigned to create 3 new and equal groups (n = 10). These bacterial leakproof specimens were submitted to a dye extraction setup. Each specimen was placed into a plastic vial with 5 mL of 2% methylene blue for 48 hours. After storage, the specimens were rinsed with tap water and dissolved in nitric acid. A sample of 100 microL of the supernatant from each specimen was analyzed in a UV-Visible spectrophotometer to determine the amount of methylene blue leakage. The log-rank test showed no significant difference in the bacterial leakage pattern among the groups (P > .05). In the dye extraction analysis, Kruskal-Wallis H test was unable to detect significant differences among all experimental groups (P > .05). The 3 filling techniques displayed similar leakage for both leakage models. Moreover, the present study demonstrated that all bacterial leakproof specimens leaked when submitted to the blue methylene extraction model.