Subcutaneous emphysema following dental procedures.

Abstract

Subcutaneous emphysema of the neck and superior mediastinum, if not postoperative, is usually associated with an ominous condition, such as tracheal rupture, bronchial rupture, or pneumothorax. Postoperatively, it usually follows lymph node biopsy or tracheostomy. Unmentioned in the medical literature, but found in the dental literature, is the occurrence of subcutaneous emphysema of the neck following dental procedures with compressed air equipment. These cases are being presented to acquaint the radiologist with this mode of occurrence. Case I: A 23-year-old white male underwent dental surgery for removal of an impacted mandibular third molar. Following mandibular block anesthesia a mucoperiosteal flap was reflected. A small amount of bone was removed with a highs-peed air turbine. The tooth was sectioned, and the two roots were removed individually. The bone was trimmed, and the wound sutured. The next day the patient returned to the clinic for follow-up. There was a minimal degree of postoperative pain, but an atypical postoperative swelling extended from the operative site down the neck to the superior chest. The swelling was fluctuant, and there was crepitus. The patient was afebrile. Radiographs of the neck and chest (Figs. 1 and 2) showed a subcutaneous emphysema of both sides of the neck from the mandible through the supraclavicular area. There was no evidence of mediastinal emphysema. The patient was put on penicillin prophylactically and followed medically. Within five days there was complete absence of symptoms and a return to normal. It is theorized that during the time periosteum was reflected and bone removed with the high-speed air turbine drill, air entered the superficial areolar tissues and dissected along the fascial plains of the neck with a resulting subcutaneous emphysema. Case II : A 27-year-old white male had an amalgam restoration of the upper right cuspid following maxillary nerve block anesthesia. Approximately thirty minutes after the procedure the patient was asked by his son to blow up a balloon. While doing so the right side of his face from the temporal region to the mandible swelled up with air. Initially, there was some pain due to the swelling; no medication was needed, however, and the air resorbed within two days. No radiographs were obtained. Discussion Shovelton (1), reviewing the American and British literature from 1900 to 1957, reported 45 cases of subcutaneous emphysema following dental operations. No serious complications were noted. Rhymes (2) and Kleinman (3) reported cases of subcutaneous emphysema during the extraction of third molars. Pearson (4) described periorbital emphysema following root canal therapy in a maxillary incisor. Rickles and Joshi (5) reported subcutaneous emphysema and air embolism that presumably caused the death of a patient. In this particular case the egress of the air was prevented because the syringe was wedged into the root canal.