# Effects of SWEEPS-Activated Irrigation and Other Methods for Elimination of Intracanal Medicaments on Push-Out Bond Strength of NeoMTA2 to Root Dentin: An In Vitro Study

## TL;DR

This study compared different irrigation methods to remove medicaments from root canals and found that using SWEEPS or PUI with calcium hydroxide improved the bond strength of NeoMTA2 to dentin.

## Contribution

The study introduces a novel comparison of SWEEPS-activated irrigation and other methods for eliminating intracanal medicaments and their impact on NeoMTA2 bond strength.

## Key findings

- SWEEPS irrigation with calcium hydroxide resulted in significantly higher push-out bond strength compared to other methods.
- Calcium hydroxide groups showed higher bond strength than triple antibiotic paste groups regardless of irrigation method.
- Passive ultrasonic irrigation improved bond strength more than conventional syringe irrigation for calcium hydroxide and triple antibiotic paste.

## Abstract

Objectives: This study evaluated the effects of laser-assisted irrigation, conventional syringe irrigation (CSI), and passive ultrasonic irrigation (PUI) for elimination of intracanal medicaments on push-out bond strength (PBS) of NeoMTA2 to root dentin.

Materials and Methods: In this in vitro study, 150 extracted single-rooted mandibular premolars were decoronated and standardized with a certain root length. The canals were instrumented to simulate immature roots and randomly assigned to three experimental groups (n = 45) using either triple antibiotic paste (TAP), double antibiotic paste (DAP), or calcium hydroxide (CH) as intracanal medicament and one no-medicament control group (n = 15). After 28 days, the experimental groups were randomly divided into three subgroups (n = 15) according to the irrigation method using either erbium-doped yttrium aluminum garnet (Er:YAG) laser shockwave-enhanced emission photoacoustic streaming (SWEEPS), CSI, or PUI. A dentinal ring was then obtained from the coronal part of each root, and its lumen was densely filled with NeoMTA2. After 1 week, the PBS was measured using a universal testing machine. Data were analyzed by ANOVA and Tukey and Dunnett tests (alpha = 0.05).

Results: The interaction effect of the irrigation technique and medicament type on PBS was significant (p < 0.05). The PBS in all groups was significantly lower than the control group (p < 0.01) except in CH-SWEEPS (p = 0.741). In the experimental groups, the PBS of the SWEEPS subgroup was significantly higher than other subgroups (p < 0.001). The PBS of PUI was higher than CSI in CH and TAP groups (p < 0.001). The PBS of CH was significantly higher than TAP in CSI, and DAP and TAP in PUI and SWEEPS groups (p < 0.05).

Conclusion: In this in vitro study, regardless of the irrigation method, higher PBS of NeoMTA2 to root dentin was achieved in CH groups compared to TAP. A higher PBS was also achieved when SWEEPS and PUI methods were used to eliminate CH in comparison to TAP and DAP.