Department of Oral and Maxillofacial Surgery, University of California, San Francisco, CA 94143-0440,
J Am Dent Assoc. 2009 Dec;140(12):1517-22. doi: 10.14219/jada.archive.2009.0103.
Local anesthetic needle fractures occur rarely. Since reports are uncommon, the mechanism and optimal treatment remain controversial.
The author reviewed 16 cases of needle fracture that were reported during a 25-year period in one academic institution.
Of 16 needle fractures, 15 occurred in connection with an inferior alveolar nerve block, and one occurred in connection with a posterior superior alveolar block. Of the 16 fractures, 13 involved a 30-gauge needle. Five of the patients involved were younger than 10 years. The oldest patient was 28 years old. In all cases, a surgeon retrieved the needle, often with radiological guidance, while the patient was under general anesthesia in an operating room.
Most needle fractures occur during the administration of inferior alveolar nerve blocks, often with 30-gauge needles and in children who are reported to have moved suddenly and violently as the dentist gave the injection. Dentists should avoid burying any needle up to the hub (so as to ensure the possibility of immediately retrieving the needle intraorally), avoid using 30-gauge needles to administer inferior alveolar nerve blocks and avoid bending the needle before inserting it.
局部麻醉针断裂很少见。由于报告少见，其机制和最佳治疗方法仍存在争议。
作者回顾了在一个学术机构的 25 年期间报告的 16 例针断裂病例。
在 16 例针断裂中，15 例与下牙槽神经阻滞有关，1 例与后上牙槽神经阻滞有关。16 例骨折中有 13 例涉及 30 号针。涉及的 5 名患者年龄均小于 10 岁。最年长的患者为 28 岁。在所有情况下，外科医生都在手术室全麻下通过影像学引导来取出针，通常是在患者体内。
大多数针断裂发生在下牙槽神经阻滞注射时，通常使用 30 号针，并且在儿童中，牙医在注射时突然剧烈移动。牙医应避免将任何针埋到针座（以确保可以立即在口腔内取出针），避免使用 30 号针进行下牙槽神经阻滞，并且避免在插入针之前弯曲针。
