Cytocompatibility of calcium hydroxide medicament combined with cationic peptide – An in vitro study on L929 fibroblast cells

Background: Intracanal medication is recommended after the debridement of the canal to eliminate bacteria to prevent apical periodontitis. Combining calcium hydroxide (CH) with DJK-5 peptide will improve the penetration of medicament into root canal dentin. Aim: This study was performed to evaluate the cytotoxicity of a combination of DJK-5 peptide with CH on murine fibroblast cells. Settings and Design: This is an in vitro experimental study performed using the L929 fibroblast cells. Materials and Methods: L929 fibroblast cells were grown in Dulbecco’s Modified Eagle’s Medium and administered with DJK-5 peptide at a concentration of 10 µg/mL, CH+ saline, CH+ 2% chlorhexidine (CHX), 2% CHX, and CH+ DJK-5 for 24 h and 48 h. Cytotoxicity assessment of the treatments was carried out using the methyl thiazolyl tetrazolium assay and Live/Dead assay by acridine orange and ethidium bromide dual-fluorescence staining. Statistical Analysis: One-way analysis of variance was used for group-wise comparison of cytotoxicity of the test compounds. Pairwise comparison between groups was analyzed by Tukey’s test. Results: The DJK-5-treated group exhibited no cytotoxicity at 24 h and 48 h and exposure time points. Highest cytotoxicity was exerted by the 2% CHX-treated group, which increased when combined with CH, and the cytotoxicity increased with time. Combining the DJK-5 with CH reduced the cytotoxicity when compared to CH or CHX alone. Conclusions: At its used 2% concentration, CHX was found to exhibit high cytotoxicity. The least cytotoxicity was found in DJK-5-treated cells, and it also significantly alleviated the cytotoxicity rendered by CH treatment.