Abstract
Background/Objectives: Residual EDTA may persist after smear-layer removal and after the application of contact sealers during setting. This in vitro study compared the effect of 1 min of pre-setting surface contact with 17% EDTA (vs. distilled water) on a calcium silicate-based sealer (AH Plus Bioceramic Sealer) and an epoxy resin-based sealer (AH Plus). Methods: Discs were prepared (N = 108) in a 2 × 2 design (n = 27/group); per group; n = 12 were used for solubility followed by eluate pH using the same specimens/eluates after 24 h immersion in distilled water; n = 12 were used to test Vickers microhardness on an independent set after setting; and n = 3 were used for SEM/EDS. Results: Data were analyzed at α = 0.05 using Kruskal-Wallis tests followed by Bonferroni-adjusted pairwise Mann-Whitney U tests for solubility and eluate pH, and one-way ANOVA was performed followed by Tukey's post hoc test to assess the microhardness. Solubility differed among groups (p < 0.001) and was higher for the bioceramic sealer than for the resin sealer; pre-setting EDTA exposure increased solubility for the AH Plus Bioceramic Sealer (0.86 ± 0.08% to 1.30 ± 0.16%) and decreased solubility for AH Plus (0.34 ± 0.04% to 0.22 ± 0.03%) (p < 0.05). The eluate pH also differed among groups (p = 0.001) and was higher for the bioceramic sealer (≈11.7) than for the resin sealer (≈8.7-9.3), with no within-material differences (p = 0.999 and p = 0.851). Microhardness differed among groups (p < 0.001) and was higher for AH Plus (239.70-246.92 HV) than for AH Plus Bioceramic (131.72-170.83 HV); EDTA reduced microhardness only for the bioceramic sealer (p < 0.001), with no significant change for AH Plus (p = 0.475). Descriptive SEM/EDS findings suggested increased surface irregularities and lower surface Ca for AH Plus Bioceramic after EDTA exposure (12.68 to 7.31 wt%). Conclusions: Pre-setting EDTA contact therefore produced material-dependent changes in early properties and adverse surface-related effects in the calcium silicate-based sealer, supporting thorough chelator removal before obturation.