手術性根管治療常用於消除無法用非手術性根管治療清潔的根尖感染，或是當無法達到緻密封填的根尖處執行逆充填。面對根管治療失敗，非手術性根管再治療通常為第一選擇，當非手術性根管治療失敗或無法提供病人更好的預後時就會考慮手術性根管治療。手術性根管治療有其適應症與禁忌症，不同牙齒條件下、所用材料及工具等皆會影響成功率。本文敘述一非手術性根管再治療失敗的患者，因有較難移除之補綴物而採用手術性根管治療，術後一年追蹤狀況良好，並藉此探討非手術性根管治療失敗原因和如何藉由手術性根管治療達到更好預後。

Endodontic surgery is commonly used for removing infected portions of the root apex that cannot be cleaned through non-surgical endodontic treatment, or also for retrograde filling. Non-surgical endodontic treatment is usually the first choice when treating endodontic failed cases, but in some conditions, we must consider endodontic surgery for a better outcome. There are many key factors affecting the success rate, and the evaluation of clinical conditions before treatment planning is important for achieving a better prognosis. In this article, a 69-year-old woman had previously received non-endodontic treatment but resulted in failure. Due to difficulty of removing her prosthesis, the surgical method of endodontic treatment was chosen. A one-year follow-up showed good results. Reasons of failure in non-surgical endodontic treatment will be discussed and also how surgical endodontic treatment will provide a better prognosis.