The use of modified nickel–titanium rotary file for preparing staging platform to retrieve instrument fragments from narrow and curved canal

Staging platform (SP) uses a modified Gates Glidden (GG) to help retrieve separated instruments deep in the root canal. However, GG drills may cause damage or severe dentin loss. A 46-year-old male patient was referred to the endodontic postgraduate clinics complaining of pain on biting related to the mandibular right second molar (#47). The preoperative periapical radiograph of #47 showed a previously initiated root canal treatment with an approximately 8-mm separated instrument in the apical third of a curved mesiolingual canal. A nickel–titanium (NiTi) rotary file size 25/0.04 was flattened with a carbide bur. The modified file was then used to create a centered SP. After SP was achieved, an ultrasonic tip was used at lower power for the trephination of dentin. The fragment became loose, and retrieval was achieved. The use of a modified NiTi rotary file presented a safe and alternative option to establish SP for instrument retrieval instead of using GG drills.