Subcutaneous Emphysema Following Subgingival Polishing Using an Air Polishing System With Subgingival Nozzle: A Case Report

BACKGROUND: Subcutaneous facial emphysema (SFE) is a rare but potentially serious complication of dental procedures involving pressurised air. While most historically reported cases were associated with air-driven handpieces, more recent literature has also implicated air-polishing systems. However, reports related to the use of subgingival air-polishing nozzles in periodontal pockets remain limited. CASE PRESENTATION: The presented case demonstrates an SFE that occurred following the use of an air-polishing system in a deep periodontal pocket. A glycine-based air-powder abrasion was used in a 5 mm deep periodontal pocket for biofilm eradication. After which, a periorbital and right cheek swelling arose. Hospitalisation was essential for close surveillance, and antibiotics were administered to control microbial spread. After 3 days, the patient was discharged in a stable condition and without any further complications. CONCLUSION: SFE may occur during subgingival air polishing, even during supportive periodontal therapy and at sites without bleeding on probing or suppuration. This case highlights that the safety of subgingival air-polishing procedures should not be generalised across all devices and protocols. Careful case selection, strict adherence to device-specific instructions, and early recognition of swelling and crepitus are essential for prompt diagnosis and management.