Surgical vs. non-surgical endodontic retreatments: A PennEndo database study

Objectives: The objective of this study was to determine the indications for surgical and non-surgical endodontic retreatments at the University of Pennsylvania graduate endodontic clinic through data compilation of the PennEndo database. The database contains over 1050 cases dating from the year 2000 to the present.

Methods: A multiple regression model was constructed with surgical vs. non-surgical retreatment being the outcome assessed. The independent variables were biological or technical reasons for retreatment, presence of respected or altered canal morphology, type of coronal/intra-coronal restoration, and presence or absence of periapical radiolucency. The odds for these independent variables for both of the retreatment methods were determined with the help of an SAS statistical package. A p value of less than 0.05 was considered significant.

Results: 305 of the chosen cases were apical surgeries and 745 were non-surgical retreatments. Anterior teeth were 61 times more likely to undergo retreatment for biological reasons. This likelihood rose to 136 times when both biological and technical reasons coexisted. Premolars and molars were less likely to undergo retreatment if the quality of the crown was satisfactory (15 and 24 times less likely respectively). In the absence of a post, premolars were 72 times more likely to undergo non-surgical retreatment than apical surgery. Molars with altered root canal morphology were 74 times less retreated than subjected to apical surgery. In addition, molars with obturations of good length were 12 times less likely to be non-surgically retreated. Generally, all root canal treated teeth open to the oral cavity went through non-surgical retreatment.

Conclusions: The results indicate that tooth position played a role in the method of retreatment. The statistically significant variables that effected the decision making process were biological or technical reasons, quality of crown, presence of the post, altered root canal morphology, and length of root canal obturation.