Physicochemical and biological properties of three calcium silicate-based root canal sealers

Calcium silicate based root canal sealers exhibit diverse physicochemical and biological properties that may influence periapical tissue responses. This study compared three sealers, Grey MTA Plus (MP), BioRoot RCS (BR), and Bio C Sealer (BC), using ProRoot MTA (PM) as a mechanistic reference material.

Physicochemical properties, including pH, solubility in deionized water (n = 5), and elemental release (Ca, P, Bi, Pb, K, Mg; n = 3), were evaluated. Human periodontal ligament cells were used to assess cytotoxicity by CCK 8 assay, mineralization by Alizarin Red S staining, and gene and protein expression of IL 6 and MMP 1 by qRT PCR, ELISA, and Western blot (n = 3 independent experiments). MAPK pathway activation was analyzed in cells treated with BR. Statistical analysis was performed using one way ANOVA followed by Tukey's post hoc test after verification of assumptions.

All materials exhibited alkaline pH values above 11. BC and BR showed higher solubility than PM under the tested conditions, whereas PM and MP released higher levels of calcium and were associated with increased mineralization. BC and BR reduced cell viability at higher concentrations and longer exposure times, particularly under serum free conditions. IL6 mRNA expression was reduced in BC and BR, but IL 6 protein levels were unchanged. In contrast, BR increased MMP 1 protein secretion. BR also induced phosphorylation of p38, JNK, and ERK1 2, and inhibition of these pathways reduced MMP 1 secretion.

PM and MP showed higher calcium release and were associated with increased mineralization, whereas BC and BR showed higher solubility and concentration dependent cytotoxicity. BR increased MMP-1 secretion and was associated with MAPK activation. These findings are based on in vitro conditions and should be interpreted with caution.