Biofilms and microbial aggregates are the common mechanisms for the survival of bacteria in nature. In other words, the ability to form biofilms has been regarded as a virulence factor. Understanding the virulence of these endodontic microbiota within biofilm is essential for the development of novel therapeutic procedures for intracanal disinfection. It play an essential role in several infectious diseases such as pulp and periradicular pathosis. Successful treatment of these diseases depends on biofilm removal as well as effective killing of biofilm bacteria. However, there is a need for all of this information to be translated into improvements in clinical practice and treatment outcomes.