Development of a Core Outcome Set in Endodontics (COS-ENDO): Part 2 - COS-ENDO for Studies of Nonsurgical Root Canal Treatment and Retreatment in Permanent Teeth.

INTRODUCTION

Methodological heterogeneity and reporting bias complicate interpreting endodontic outcomes. Supported by the American Association of Endodontists and its Foundation, this study developed the Core Outcome Set in Endodontics (COS-ENDO) to standardize reporting for studies of Nonsurgical Root Canal Treatment/Retreatment, Surgical Endodontics, Vital Pulp Therapy, Apexification, and Regenerative Endodontics. This article, Part 2 of a 5-part series, focuses on COS-ENDO for Nonsurgical Root Canal Treatment/Retreatment, while other parts address the remaining treatments.

METHODS

Outcomes were identified through scoping reviews, a qualitative study with patients, and a web-based survey of American Association of Endodontists practicing members. In a 2-round Delphi survey, clinicians, patients, and researchers rated outcomes on a 9-point scale. Ratings were assessed against consensus criteria, and a virtual meeting finalized COS-ENDO.

RESULTS

Of the 97 invited participants to Round 1, 77 registered, and 73 (24 Academicians/Researchers, 26 Clinicians, and 23 Patients (or their parents/caregivers)) assessed 39 outcomes, with 18 excluded. The remaining outcomes-7 achieving consensus for inclusion and 14 lacking consensus-advanced to Round 2 for re-rating by 70 participants. This resulted in 9 outcomes achieving consensus for inclusion, and 12 lacking consensus. In the final meeting, 16 participants finalized the COS-ENDO for Nonsurgical Root Canal Treatment/Retreatment, including Tooth survival, Pain, Signs of infection, Radiographic evidence of periradicular healing, Success, Functional tooth, Need for further intervention, and Adverse events/Complications.

CONCLUSIONS

COS-ENDO is an important step in standardizing outcome reporting in endodontics, ensuring consistent reporting and enhancing research utility. Further efforts are needed to establish optimal measurement methods.