Direct pulp capping is an alternative treatment for dental pulp injuries caused by decay, trauma, or cavity preparation. Ornidazole is an antibiotic that is commonly used to treat dental infections against anaerobic bacteria. The purpose of this study was to examine the feasibility of using ornidazole-loaded nanofibers as a coating material for pulp capping. Ornidazole-free and ornidazole-loaded nanofibers were prepared with various polymeric biomaterials, including chitosan, polycaprolactone, and polyethylene oxide using electro-spinning method. After characterization (scanning electron microscopy, mechanical properties, contact angle measurements) of the nanofibers, WST-1 tests performed at 24, 48, and 72 h showed that the nanofibers of both groups had minimal cytotoxic effects on pulp cells. Furthermore, pathological examinations showed higher numbers of cells on the nanofibers in the 72-h samples. Antimicrobial activity tests with omidazole showed more significant formation of inhibition zones in with the ornidazole-loaded nanofibers, demonstrating their potential applicability for direct pulp capping. (C) 2017 Elsevier B.V. All rights reserved.