Subcutaneous emphysema of dental origin - Two case reports with a comprehensive review of literature from 1965 to 2020, with an emphasis on timely management

Subcutaneous emphysema (SE) is a rare but possible complication of dental treatment resulting from the usage of high-speed air-driven instruments and introduction of irrigating solutions like hydrogen peroxide into soft tissues. Two case reports are described here, namely (a) drying of root canals using a three-way syringe by "Venturi" technique and (b) accidental injection of hydrogen peroxide instead of local anesthesia in an infiltration technique. A review of the literature is done wherein a search for terms such as pneumomediastinum, mediastinitis, embolism, or extensive SE (ESC) from 1965 to 2020 using the PubMed search engine was done and the results were tabulated. Since the number of cases and complications reported are on the rise,data regarding diagnosis, investigations, and a management protocol with an emphasis on prevention have been elaborated. Methods such as reductive manipulation or "counter incision," as incited from medical literature, have been suggested to reduce morbidity and mortality. In both of the case reports, subcutaneous cervicofacial emphysema resolved briefly due to the effectual reduction maneuver implemented promptly.