Foreign body ingestion induces various complications during the induction of and emergence from anesthesia. These complications include inconsequential mucosal scratches, abrasion, laceration, esophageal stricture, necrosis, retropharyngeal abscess formation, hemorrhage, obstruction and perforation. We experienced a case of esophageal perforation after ingestion of a dental prosthesis during emergence. A 71-year-old female patient received general anesthesia for a lumbar laminectomy. At postanesthesia care unit, she complained of a sore throat and found that her dental prosthesis was missing. The impacted dental prosthesis was found at the T7 level, which was followed due to its perforation through the esophageal wall, causing mediastinitis. She underwent an operation for the esophageal repair and was discharged with slight chest discomfort due to operation, after 10 days.