Comparison of smear layer removing efficacy of Cold Atmospheric Pressure (CAP) Plasma Jet with different chelating agents. An ex-vivo study.

The present study aimed to assess the effectiveness of different final irrigation regimens (Cold Atmospheric Pressure Plasma Jet, MTAD, and EDTA) in removing the smear layer from intra-radicular dentin using a Scanning Electron Microscope (SEM). Eighty-four mandibular premolars were prepared with ProTaper Universal hand files and were equally divided into four groups i.e. Normal saline (control), EDTA, MTAD and CAP Plasma Jet. Prepared samples in the control, EDTA and MTAD groups were irrigated with 5 milliliters of the irrigant, and it was retained for 2 min. In the CAP Plasma Jet group, the plasma plume was directed towards the canal lumen for 2 min. The smear layer removal of all the groups was evaluated at the coronal, middle and apical thirds. Statistical analysis was performed using Kruskal-Wallis test followed by Dunn's test. Evaluation by SEM showed that the smear layer removal ability of MTAD and EDTA were significantly better than CAP Plasma Jet ( p  < 0.05). While CAP Plasma Jet showed results comparable to EDTA in the coronal third. In the middle and apical third of the canal, its effect was comparable to the control group ( p  > 0.05). MTAD and EDTA aided in better smear layer removal than the CAP Plasma Jet in the coronal, middle, and apical third of the test samples. CAP Plasma jet performed better in the coronal third.