Authors: Ingle J, Bakland L.
Title: Endodontics 5th edition.
Journal: Philadelphia: Lea & Febiger
Date: Jan 2002
Citation: 747-57
Category: Success and Failure
Evidence-based Ranking: 5
Purpose/Objective: To discuss the outcome of endodontic treatment and retreatment.

Discussion: The chapter discusses the Washington study in detail. It was found that older teeth were more successfully obturated than young teeth with large diameter canals. Mandibular 1st premolar had a failure rate of 11.45% while mandibular 2nd premolar had 4.54% due mainly to canal anatomy wherein the 1st premolar has branching canals, apical bifurcation and trifurcation. The most frequent cause of failure is incomplete obturation (58.66%) followed by root perforation (9.61%). Thus the 2 greatest cause of failure is inadequate cleaning and shaping and incomplete obturation. 3 main categories of failure were given. 1. Apical percolation: incomplete obturation, unfilled canal, silver point inadvertently removed. 2. Operative errors: root perforation, grossly overfill or overextended and broken instrument. 3. Errors in case selection: external root resorption, coexistent periodontal periradicular lesion, developing apical cyst, adjacent pulpless tooth, accessory canal unfilled, constant trauma, perforation of the nasal floor.

Conclusion: The more extensive and severe the endodontic pathosis, the poorer the prognosis. In other words, the higher the percentage of success is with teeth with vital pulps and the worst prognosis is for those with long standing periradicular lesions. Also, the more dental treatment is done, the poorer the prognosis. Good NSRCT has the best prognosis and the worst prognosis lies with teeth that have been retreated nonsurgically and then retreated surgically once or twice more.

ReviewerÂ’s comments: A good literature review of success and failure in endodontics.