Effect of exposure to etidronic acid on the bond strength of calcium silicate-based cements after 1 and 21 days: an in vitro study.

BACKGROUND: After reparation of root perforations with calcium silicate-based cements (CSBC), the surface of the material is expected to be exposed to root canal irrigants (RCI) while resuming the root canal treatment. METHODS: The aim of this study was to compare the effect of exposure to a mixture of sodium hypochlorite (NaOCl) and etidronic acid (HEBP) or other irrigants on the Push Out Bond Strength (POBS) of CSBC after two different setting times. 240 root slices 1 mm thick were obtained from single-rooted human teeth. A 1.4 mm diameter perforation was performed on each slice and filled with Biodentine (BD) or ProRoot MTA (PMTA). After 1 or 21 days they were exposed to 17% ethylenediaminetetraacetic acid, 5.25% NaOCl, a mixture of 5.25% NaOCl and 9% HEBP (NaOCl + HEBP) or saline (n = 15) and submitted to a push-out test. POBS results were analysed with ANOVA and Tukey tests. RESULTS: BD showed higher POBS than PMTA after 1 day (p < .05). After 21 days no differences were found between materials. After 1 day exposure to NaOCl + HEBP resulted in higher POBS, compared to the other irrigants (p < .05). CONCLUSION: POBS results are influenced by the cement, the setting time and the exposure to irrigants.

Effect of exposure to root canal irrigants on the push-out bond strength of calcium silicate-based cements.

OBJECTIVES: The aim of this study was to compare the push-out bond strength (POBS) of three calcium silicate-based cements (CSBC) after exposure to saline, sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA), and a mixture of NaOCl and etidronic acid (NaOCl+HEBP) in simulated perforation. MATERIALS AND METHODS: A total of 180 dentin slices were perforated and then filled with either Biodentine (BD), ProRoot MTA (PMTA), or Total Fill (TF). After 1 week, specimens in each group were divided into 4 subgroups (n = 15) according to the root canal irrigant (RCI) that their coronal surface was exposed to: saline, 5.25% NaOCl, 17% EDTA, or a mixture of 5.25% NaOCl and 9% HEBP (NaOCl+HEBP). A push-out test was performed, and the failure pattern was assessed. POBS data were analyzed with ANOVA and Tukey post hoc tests and the failure patterns with chi-square test. RESULTS: No differences were found when comparing the effect of RCI on the POBS of PMTA. BD showed significantly higher POBS values after exposure to NaOCl+HEBP (p < .05), and those of TF were significantly lower after exposure to EDTA (p < .05). No differences in the failure patterns were found among groups. CONCLUSION: NaOCl+HEBP had no detrimental effect on the POBS of CSBC. CLINICAL RELEVANCE: The mixture of sodium hypochlorite and etidronic acid may be considered as an alternative irrigant when treating root perforations.