A retrospective comparison of outcome of root canal treatment using two different protocols.

Objectives: This retrospective study (1) compared the outcome of root canal treatment performed by an endodontist using 1 of 2 different protocols and (2) evaluated the influence of factors affecting outcome.

Study Design: A total of 200 teeth and 489 roots (Protocol A, 83 teeth/200 roots; Protocol B, 117 teeth/289 roots) treated nonsurgically with root canal 4 to 5 years previously were examined clinically and radiographically according to strict criteria. Generalized estimating equations were used to perform logistic regression to analyze data.

Results: The rate of complete healing for Protocol A (78%) was similar to that of Protocol B (76%). The pulpal status (odds ratio = 2.399, P =.040) and presence (odds ratio = 1.696, P = 0.015) and size (odds ratio = 0.823, P <.001) of periapical lesion were the only factors significantly affecting treatment outcome.

Conclusion: The preoperative status of the pulp and the presence and extent of periapical periodontitis were important prognostic determinants of treatment outcome in this study.