Solubility of calcium silicate-based endodontic sealers in acidic and neutral pH using phosphate-free buffers

Abstract

Abstract: This study aimed to evaluate the solubility of calcium silicate-based endodontic sealers under acidic and neutral pH conditions using phosphate-free buffered solutions. The solubility of three calcium silicate-based sealers (BioRoot RCS, Bio-C Sealer, and AH Plus Bioceramic) and an epoxy resin-based sealer (AH Plus Jet) was evaluated according to ISO 6876:2012 guidelines, with modifications. Specimens (n = 12 per sealer) were immersed in phosphate-free buffered solutions at pH 5 and 7 and stored at 37°C for 24 hours, 7 days, and 30 days. Solubility was calculated as the percentage of initial mass loss. Statistical analyses were conducted using one-way ANOVA, Tukey's post hoc test, and independent t-tests (p < 0.05). AH Plus Jet met ISO 6876:2012 solubility standards at all time points, while all calcium silicate-based sealers exceeded the acceptable limit. Acidic pH significantly increased the solubility of these sealers (p < 0.05), except for BioRoot RCS at 30 days. Among the calcium silicate-based sealers, BioRoot RCS exhibited the lowest solubility, followed by Bio-C Sealer, whereas AH Plus Bioceramic showed the highest solubility and disintegrated after 7 days, preventing evaluation at 30 days. In contrast, AH Plus Jet remained stable under both pH conditions, exhibiting a slight mass gain over time. Overall, acidic pH increased the solubility of calcium silicate-based sealers, whereas AH Plus Jet remained stable and compliant with ISO 6876:2012 standards.