Which organism is most commonly associated with failed endodontic procedures?

Enterococcus faecalis is frequently identified as a key organism associated with failed endodontic procedures. This bacterium is notorious for its resilience in the root canal environment, demonstrating a high level of resistance to various antimicrobial agents and treatments commonly used in endodontic therapy. It can survive in nutrient-poor conditions and is capable of forming biofilms, which complicates its eradication during standard treatment procedures.

Moreover, Enterococcus faecalis is often found in cases of persistent apical periodontitis, where conventional endodontic therapy fails to achieve the desired outcome. Its presence in these scenarios suggests that it plays a significant role in the failure of root canal treatments, making it a critical focus for clinicians attempting to understand and address treatment failures.

In contrast, other organisms listed may be involved in endodontic infections but do not have the same level of association with treatment failures as Enterococcus faecalis. For example, while Streptococcus mutans is primarily linked with caries and not specifically with endodontic treatment failure, Propionibacterium and Actinomyces are more often found in specific contexts, such as in certain types of infections but are not as directly associated with failed endodontic outcomes as Enterococcus faecalis