A rare case of long-term retention of a fractured endodontic instrument in the alveolar bone without adverse effects on the successor tooth.

BACKGROUND: Fracture of endodontic instruments during primary tooth treatment is rare, and limited evidence exists regarding the lon g-term impact of retained fragments on the development of successor teeth and surrounding alveolar bone. CASE PRESENTATION: This report describes a 33-year-old woman in whom a radiopaque foreign body was incidentally discovered in the periapical region of the right maxillary first premolar (#14) during a routine dental examination. Cone-beam computed tomography (CBCT) revealed a well-defined, high-density object measuring 3.61 mm × 0.66 mm, located approximately 0.5 mm from the root apex. The patient recalled undergoing endodontic treatment during childhood. Based on imaging features and clinical history, the object was presumed to be a fractured instrument fragment retained during primary root canal therapy. The foreign body caused no inflammatory signs, and both the permanent tooth and surrounding alveolar bone developed normally. After multidisciplinary consultation, conservative management was selected. The patient remained asymptomatic during a one-year follow-up period. CONCLUSIONS: This case illustrates that small endodontic fragments retained from primary tooth treatment may remain embedded in the alveolar bone for decades without inducing inflammation or disrupting the development of permanent teeth or periodontal tissues. In cases where foreign bodies are asymptomatic and radiographically stable, conservative monitoring may be a clinically reasonable approach.