A new approach to the basic principles of endodontics.

The basic principles on which successful endodontic therapy depends have been commonly accepted as (1) debridement, (2) sterilization and (3) obturation. Each of these principles is subjected to critical evaluation. Because of the morphological complexity of most root canals complete debridement is not possible. No sampling technique is yet available to ensure total sterility of the prepared root canal nor is it possible to ensure that the root canal system is hermetically sealed by the filling material. Although it has been shown that 43 per cent of biopsies from the periapical area of endodontically involved teeth show evidence of cyst formation, the fact that up to 90 per cent of cases show evidence of healing following endodontic treatment without surgery indicates that radicular cysts can resolve without surgical intervention. In the light of these findings it is suggested that the basic principles should be accepted as (1) adequate debridement, (2) adequate obturation and (3) trephination where indicated.