How useful is root canal culturing in predicting treatment outcome?

Abstract

Microbial control--fundamental to healing of apical periodontitis--is central to endodontic practice. The effectiveness of antibacterial measures is generally monitored (in clinical research studies) by microbiological root canal sampling (MRS), which is often used as a predictor for healing. This article addresses the question of the extent to which positive or negative cultures at time of obturation are able to predict treatment outcome. To date only one small clinical study has attempted to relate the treatment outcome to intraradicular bacterial status (p = 0.025, Fisher's exact test): the strength of the association was not great, with a wide confidence interval (odds ratio = 6.8; 95% C..