Figure 1: The original protocol developed in our study allows recovering the dental pulp and minimizes the risk of laboratory-acquired contamination of the specimen. The tooth was encased into sterile resin (1a); the apex was sterilely sectioned (1b) to give access to the canal system (1c); solutions were injected (1d); after incubation, the tooth was put upside down into sterile tube (1e) and centrifuged.