(PO61) Retreatability of EndoSequence® BC Sealer™ HiFlow by Adding an Aqueous Solution in Endodontics

Abstract: When RCT fails, retreatment of the case usually requires the removal of the previous root canal fill (RCF). The aim of our research was to evaluate the retreatability of teeth initially filled with EndoSequence® BC Sealer™ HiFlow utilizing chloroform followed by 18% HCl, 18% HCl alone, chloroform alone, or saline solution. Forty extracted single canal teeth were decoronated and obturated utilizing a single-cone gutta-percha technique and BCS, stored for one week in an incubator, and then we attempted to remove the previous RCF. Teeth were divided into 4 different groups (n=10). Canals were then cleaned using heat, rotary instruments, hand files, and specific solutions. Group A was cleaned by using only saline solution; Group B was cleaned by using only chloroform solution; Group C was cleaned by using only 18% HCl solution; and Group D was cleaned by using chloroform + 18% HCl. ImageJ software was used to evaluate and quantify the amount of obturation material left in the canal after cleaning. The pairwise comparison showed no significant difference between chloroform and 18% HCl alone (p = .82). However, chloroform + 18% HCl treatment showed a significant difference compared to chloroform alone (p = .026), 18% HCl alone (p = .021), and saline alone (p = .003). The result of this study indicates that chloroform followed by 18% HCl was superior in removing the previous RCF compared to either solution alone in canals filled with gutta-percha and BCS. However, regardless of the solution used, patency can be achieved.