Severe bilateral subcutaneous emphysema after prophylactic treatment: a case report.

Subcutaneous emphysema is the accumulation of gas or air in loose subcutaneous connective tissue. The use of air-driven handpieces in dental procedures is a common iatrogenic cause of intraoral mucogingival barrier disruption by high-pressure air. This case report describes a 60-year-old woman who underwent prophylactic periodontal treatment with an air-abrasive device and subsequently developed severe bilateral subcutaneous emphysema, extending from the temporal region to the thoracic and mediastinal spaces. Subcutaneous emphysema was suspected based on clinical examination, and paranasal CT was performed for definitive diagnosis. Chest CT was conducted for further evaluation, followed by consultation with the Department of Thoracic Surgery. The patient was admitted for supportive care and prophylactic antibiotics. After 4 days of hospitalization, the symptoms had nearly resolved, and a follow-up paranasal CT showed significant air resorption. The patient was discharged without complications. Although generally benign and self-limiting, subcutaneous emphysema can lead to serious complications such as systemic infection, pneumothorax, and air embolism. This case highlights the importance of prompt diagnosis and appropriate management to prevent further complications.