The effect of nonthermal plasma on the push-out bond strength of two different root canal sealers.

Background: An optimum bonding between the sealer and dentin is important for impermeable root canal filling and many procedures were applied to improve root canal dentin and in turn the bond strength between the sealer and dentine. There is lack of sufficient data on the effect of nonthermal plasma application on the bond strength of sealers to the root canal dentin. Aim: The purpose of this study was to evaluate the effect of NAP on the push-out bond strength (PBS) of a bioceramic and resin-based root canal sealer (RCS) to root canal dentin. Materials and Methods: Forty single-rooted mandibular premolars were decoronated. After preparation and final irrigation, the specimens were divided into four groups (n = 10). Group AH: Root canals were filled with gutta-percha (GP) and AH Plus RCS, Group P-AH: Root canals were filled with GP and AH Plus RCS following the NAP application, Group BC: Root canals were filled with GP and Endosequence BC RCS, and Group P-BC: Root canals were filled with GP and Endosequence BC RCS following the NAP application. Then roots were sectioned horizontally to obtain similar to 1 mm thick dentin disks. PBS test was performed to the second (coronal) and fourth (middle) slices. Data were analyzed with the Kruskal-Wallis and t-test. Results: There was a statistically significant difference among the groups for both coronal and middle regions (P < 0.05). P-BC group showed higher PBS than AH and P-AH groups in the coronal region. P-BC group showed higher PBS than the other groups in the middle region. Conclusions: The use of NAP did not influence the push-out bond strength of AH-Plus sealer to the root canal dentin. The Endosequence-BC sealer showed a better bond strength than the AH-Plus sealer after NAP application.