Life-threatening events such as aspiration of a self-exfoliated tooth (SET) are not uncommon. The risk is particularly high in patients with restricted mouth opening, making it difficult to remove foreign bodies from the oral cavity. This situation is particularly concerning for oncology patients, who may already have compromised airway protection. We report a case of a patient with severe trismus who retained a SET in the oral cavity and was unable to expel it due to severely restricted mouth opening. A simple, non-invasive, and cost-effective technique using dental floss was successfully employed to retrieve the SET safely. This approach demonstrates an effective method for managing similar emergencies.