OPEN APEX (Incomplete rhizogenesis) refers to the absence of sufficient root development to provide a conical taper to the canal. The anatomy of the apical foramen changes with age as root formation has yet to be completed when teeth erupt. The completion of root development and closure of the apex occurs up to three years after eruption. Patients who present with immature apical formation pose a challenge due to the presence of large open apices along with divergent and thin dentinal walls that are susceptible to fracture. An immature tooth with pulpal necrosis and periapical pathology...

Biofilms are the 'aggregates of microorganisms in which cells are frequently embedded in a self produced matrix of extracellular polymeric substances (EPS) that are adherent to each other and/or a surface. This text book comprises of basic ultra structure of biofilms, it's development, type, composition , characteristic feature of biofilm and resistance of microbes in biofilms; approaches to biofilm prevention and current therapeutic options for endodontic biofilms explained in simplified manner after reviewing the literature.