Postsurgical endodontics.

Apical surgery is known to be an effective and practical way of treating endodontic failures. However, in spite of seemingly proper root end management, surgical failures may occur as a result of lateral canal, dentinal tubule, end retrograde leakage. Since surgical retreatment of such failures would likely result in failure, the alternative of a nonsurgical retreatment should be carefully considered. An understanding of the relationship which exists between the quality of the orthograde treatment and the surgical prognosis is necessary to properly direct the course of treatment.