Coronal leakage following three obturation techniques

Aim To compare coronal bacterial and India ink leakage in three different o bturation techniques with the smear layer having been removed. Methodology Seventy extracted single-rooted teeth were instrumented to an a pical preparation size 7 Profile Series 29 (Tulsa Dental Products, Tulsa, O K, USA). The smear layer was removed and 20 teeth were randomly obturated w ith lateral compaction, 20 teeth with vertical compaction, and 20 teeth wit h Thermafil (Tulsa Dental Products, Tulsa OK. USA). Ten teeth were used for positive (five teeth) and negative (five teeth) controls. Teeth were store d for 90 days in 100% humidity, then subjected coronally to Proteus vulgari s for 21 days to assess bacterial leakage. Following bacterial challenge, I ndia ink was placed coronally for a further 21 days, then scored according to depth of dye leakage. Results Vertical compaction leaked significantly less than lateral compacti on during bacterial challenge. However, when dye was used there were no sig nificant differences. Conclusions Bacterial leakage and dye leakage demonstrated considerable var iability. The use of a dye following bacterial testing may highlight the fa ilure of experimental devices and vertical root fractures, thus avoiding fa lse positive results found with bacterial testing alone.