A New Combination with D-Cateslytin to Eradicate Root Canal Pathogens

The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only partially eliminate bacteria, the use of intracanal medicaments is suggested to improve the eradication of the root canal pathogens. Antimicrobial peptides derived from Chromogranin A display bacteriolytic activities and are potentially excellent candidates to be combined with conventional intracanal medicaments. In this study, we combined D-Cateslytin (D-Ctl), together with calcium hydroxide (Ca(OH)2) to test for enhanced antimicrobial properties against Enterococcus faecalis. Antimicrobial activities were determined by broth dilution assays, stability of D-Ctl was assessed by HPLC and MTT tests were used to evaluate cytotoxicity. A saturated solution of Ca(OH)2 (1.7 mg/mL) was able to inhibit 58% (± 5%) of E. faecalis growth, while the combination of both 0.85 mg/mL of Ca(OH)2 and ½ MIC of D-Ctl was able to fully inhibit its growth. D-Ctl was stable against the proteases secreted by E. faecalis and showed no toxicity on human gingival fibroblasts. Besides E. faecalis, this combination was also effective in completely killing other endodontic pathogens: Parvimonas micra, Prevotella intermedia, Fusobacterium nucleatum and Candida albicans. In conclusion, D-Ctl combined with Ca(OH)2 eradicates several endodontic pathogens and could be used as an innovative intracanal medicament to reduce endodontic failures.