Cytotoxicity and Bioactivity of Five Hydraulic Silicate Cements in Human Dental Pulp Cells at Different Setting Stages

INTRODUCTION AND AIMS: Evidence regarding the biological responses of human dental pulp cells (hDPCs) to freshly mixed hydraulic silicate cements remains limited. This study aimed to evaluate the biocompatibility, mineralisation potential, and immunomodulatory effects of five hydraulic silicate cements (ProRoot MTA, Biodentine, TotalFill BC Putty, CeraPutty, and C-Root BP) at different stages of setting on hDPCs. METHODS: hDPCs were isolated from human third molars. Extraction media were prepared from the different pulp dressing materials at 15 minutes, 24 hours, and 7 days after mixing. Cell viability was assessed using the MTT assay and live/dead staining. Odonto/osteogenic differentiation was evaluated using Alizarin Red S staining. RNA extraction and quantitative real-time polymerase chain reaction were conducted to investigate the mRNA expression of inflammatory and immunomodulatory-related genes. RESULTS: Undiluted extraction media obtained from all five freshly mixed hydraulic silicate cements (15 minutes after mixing) were cytotoxic to hDPCs. In contrast, the extraction media collected after a longer setting period (7 days post-mixing) showed no cytotoxicity, except for C-Root BP. Enhanced mineralisation was observed in cells treated with extraction media derived from ProRoot MTA, Biodentine, and TotalFill BC Putty at all time points. By contrast, cells exposed to extraction media from C-Root BP and CeraPutty at the 24-hour and 7-day setting time points exhibited markedly reduced mineral deposition. Additionally, the extraction medium derived from TotalFill BC Putty downregulated the expression of inflammation-related genes in hDPCs. CONCLUSION: TotalFill BC Putty, Biodentine, and ProRoot MTA demonstrated superior performance in reference to the investigated parameters compared with CeraPutty and C-Root BP, suggesting their suitability as pulp dressing materials for vital pulp therapy procedures. CLINICAL RELEVANCE: The data may guide clinicians in selecting the most appropriate pulp dressing material based on the investigated biological parameters.