Pulp and Periradicular Pathways, Pathosis, and Closure

Abstract

This chapter talks about pulp and periradicular pathways, pathosis, and closure. The root canal system and the periodontium communicate through natural and artificial (iatrogenic) pathways. The natural pathways of communication between the root canal system and the periodontium include the apical foramen, lateral canals, and dentinal tubules. The pathological and iatrogenic pathways of communication between the root canal system and the oral cavity as well as the root canal system and the periodontium include carious pulp exposure, root perforation during access preparation, cleaning and shaping, post preparation and vertical fracture during obturation. Periradicular tissues have an almost unlimited source of undifferentiated cells that can participate in the process of inflammation as well as repair. Mineral trioxide aggregate (MTA) is the material of choice for sealing the pathways of communication between the root canal system and its external surfaces.