Comparative Analysis of Root Canal Filling Debris and Smear Layer Removal Efficacy Using Various Root Canal Activation Systems during Endodontic Retreatment.

Seong Yeon Park,Won-Jun Shon,Hae Won Choi,Mo Kwan Kang

doi:10.3390/medicina56110615

Abstract

Background and objectives: The complete removal of obturation material can be a challenge in nonsurgical root canal retreatment. The insufficient removal of obturation material is a reason for root canal retreatment failure. Materials and Methods: The purpose of this study was to assess the efficacy of different final root canal irrigation activation methods in removing debris and smear layers in the apical and middle portions of root canals during retreatment. Sixty-six distal roots of freshly extracted molars were randomly divided into six groups: (1) primary root canal treatment with no obturation (negative control); (2) retreatment with only conventional instrumentation and irrigation (positive control); (3) retreatment with additional ultrasonic irrigation using the Piezon Master 700; (4) ultrasonic irrigation with the ENDOSONIC Blue; (5) sonic irrigation with the EDDY; and (6) multisonic irrigation with the GentleWave system. Roots were split and prepared for scanning electron microscopic (SEM) evaluation. Acquired images were assessed to quantify the amount of debris and smear remaining. Results: Among the treatment groups, Group 6 had a significantly lower debris score than Group 2 (positive control) in both the middle and apical regions (p = 0.004, p = 0.012). All treatment groups showed significantly lower smear scores than Group 2 in the middle and apical regions (p < 0.05). Conclusions: The GentleWave multisonic System showed a more optimal cleaning efficacy of the root canal debris but did not differ significantly with the tested passive ultrasonic or sonic irrigation method.

Highlights

In a survey conducted by the American Association of Endodontics, 46% of all endodontic treatments were nonsurgical retreatments [1]
The ability of ultrasonic irrigation to reduce the amount of remaining filling material following root canal retreatment was tested, and the results were compared to those of conventional needle irrigation and instrumentation [9]
This study showed that the amount of debris removed in the apical and middle regions of root canal systems was greater with the GentleWave System than with ultrasonic or sonic activation

Summary

Introduction

In a survey conducted by the American Association of Endodontics, 46% of all endodontic treatments were nonsurgical retreatments [1]. Removing the previously filled obturation material from a root canal system after a primary treatment remains a challenge [3,4]. Many studies showed that even after using Ni–Ti rotary instruments developed for retreatment, filling material was not completely removed from the root canal walls [5,6,7,8]. The ability of ultrasonic irrigation to reduce the amount of remaining filling material following root canal retreatment was tested, and the results were compared to those of conventional needle irrigation and instrumentation [9]. Sixty-six distal roots of freshly extracted molars were randomly divided into six groups: (1) primary root canal treatment with no obturation (negative control); (2) retreatment with only conventional instrumentation and irrigation (positive control); (3) retreatment with additional ultrasonic irrigation using the Piezon.

Objectives

Methods

Results

Conclusion