Macrophage Modulation and Immunotoxicity by Bioceramic Endodontic Sealers

Objectives: This study aimed to evaluate the cytotoxicity and anti-inflammatory properties of two silicate-based sealers: AH Plus Bioceramic Sealer (Dentsply Tulsa Dental Specialties, Johnson City, TN, USA) and EndoSequence BC (Brasseler U.S.A, Savannah, GA, USA).
Methods: Cytotoxicity was assessed using MTT and Live/Dead assays, while inflammatory cytokine and mediator expression were analyzed in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages via ELISA and RT-qPCR.
Results: Both sealers exhibited lower cytotoxicity compared to AH Plus, with EndoSequence BC demonstrating significantly reduced cytotoxic effects compared to AH Plus Bioceramic, particularly in the undiluted group. In LPS-stimulated macrophages, EndoSequence BC effectively downregulated TNF-α and IL-6 after 48 hours, whereas AH Plus Bioceramic primarily reduced TNF-α levels. mRNA expression analysis revealed significant downregulation of TNF-α, IL-6, COX-2, and iNOS by both sealers. Additionally, both sealers modulated macrophage polarization, showing reduced M1 markers (CD86, CXCL9, CXCL10) and increased M2 markers (CD206). They also inhibited MAPK and NF-κB signaling pathways in the inflammatory macrophages.
Conclusions: AH Plus Bioceramic Sealer and EndoSequence BC Sealer exhibit excellent biocompatibility and comparable anti-inflammatory effects in LPS-induced RAW264.7 macrophages, mediated through suppressing MAPK and NF-κB pathways.