# Effectiveness of supplementary protocols for filling material removal after sealer ultrasonic activation - a laboratory investigation

## TL;DR

This study tests methods to remove dental filling material after ultrasonic activation, finding that the Clearsonic-R1 tool works best.

## Contribution

The study introduces and evaluates supplementary protocols for removing filling material after sealer ultrasonic activation in endodontics.

## Key findings

- The Clearsonic-R1 insert showed the highest effectiveness in removing filling material.
- The XP-endo Finisher had the lowest effectiveness as a supplementary removal tool.
- There was no significant difference in material removal across root thirds.

## Abstract

Ultrasonic activation of the endodontic sealer makes it difficult to remove the material during endodontic reintervention. Therefore, supplementary removal protocols should be tested to optimize the removal of the remaining filling material. This study assessed the effectiveness of supplementary protocols for filling material removal after sealer ultrasonic activation (UA). Sixty teeth were prepared and distributed into two groups: UA and No UA of the sealer before obturation. Teeth were re-instrumented and two supplementary removal protocols were tested, resulting in six groups (n = 10): NoUA; NoUA+XP (XP-endo Finisher); NoUA+CS (Clearsonic-R1); UA; UA+XP; and UA+CS. Root canals were analyzed under stereomicroscopy and scanning electron microscopy for quantification of the remaining filling material. Considering the total root canal area, the NoUA+CS group had the lowest remaining filling material compared to NoUA+XP, UA+XP and UA+CS groups (p < 0.05). When the root thirds were compared, there was no statistical difference among groups (p > 0.05). The XP-endo Finisher instrument demonstrated the lowest effectiveness when used as a supplementary step. In contrast, the Clearsonic-R1 insert exhibited the highest performance.