CARES—A New Three‐Dimensional Coding System for Classifying Teeth With Dens Invaginatus

AIM: To establish a novel comprehensive three-dimensional coding system for the classification of teeth with dens invaginatus (DI) using cone beam computed tomography (CBCT) imaging. METHODOLOGY: An initial draft classification of teeth with DI was developed by the project directors and steering group based on the interpretation of CBCT images. A group of 26 global experts then provided their perspectives on the classification via a consensus-building online Delphi process. Following the achievement of consensus, six endodontists independently examined CBCT images of teeth with DI to evaluate the reliability of the draft classification. Inter-rater reliability was employed to ascertain the agreement among the six assessors and intra-rater reliability was assessed following the re-evaluation of the identical CBCT images 3 weeks later. The steering group then revised and finalized the classification. RESULTS: The online Delphi process was completed in a single round with a 100% response rate. The inter-rater reliability score of 0.89 and the intra-rater reliability score of 0.88 revealed "almost perfect" agreement among and within the evaluators. The final CARES classification of teeth with DI includes five domains: Communication (C), cross-sectional Anatomy (A), Root formation (R), vertical Extent (E), and Supplementary features (S). CONCLUSION: The three-dimensional CARES classification system provides stakeholders with a consistent and unambiguous method of categorizing teeth with DI. The system has the potential to enhance the precision of diagnosis and clinical decision-making during the management of DI and ensures clinicians can communicate more accurately with patients and other healthcare professionals.