RESUMEN
INTRODUCTION: Third molar extraction is one of the most common surgical procedures in oral and maxillofacial surgery. Infectious complications can be estimated at 3.6% after local anesthesia. OBSERVATION: A 39-year-old female patient, presenting with important swelling of the face and neck after extraction of teeth 28 and 38 after local anesthesia. Clinical and radiographic data led to the diagnosis of facial cellulitis due to a foreign body on the sub angulo-mandibular region. Drainage under general anesthesia was performed and a fragment of anesthesia needle was removed. One month after surgery, the patient was considered cured. DISCUSSION: Breaking an anesthesia needle is a rare accident, which can occur during oral surgery under local anesthesia. Respecting the rules of good practice is essential in preventing this type of complication, especially since forensic rules for dental and oral surgery are becoming stricter.