The Hidden Dangers of Counterfeit and Replica-Like Endodontic Files: A Scoping Review of Current Evidence

This scoping review mapped and critically appraised laboratory evidence on counterfeit and replica-like nickel-titanium endodontic files, evaluating design, metallurgical composition, surface finishing, and mechanical performance to clarify clinical and regulatory implications. Comprehensive searches of major databases and key endodontic journals identified 17 in vitro studies; no clinical studies were found. Counterfeit instruments consistently exhibited design irregularities, surface defects, and altered metallurgical properties that reduced cyclic fatigue resistance and produced unpredictable mechanical behaviour, posing significant patient-safety concerns. Replica-like instruments showed heterogeneous performance, with some matching or rarely exceeding original files in specific tests but others demonstrating inferior flexibility or torsional resistance. Quality-control standards were inconsistent or lacking. These findings demonstrate that deviations in alloy processing, phase transformation, and surface finishing compromise mechanical reliability and highlight the urgent need for stronger regulatory oversight and clinical validation to safeguard practitioners and patients.