D. Pneumoparotid
Pneumoparotid is characterized by retrograde movement of air through the parotid duct, or Stensen duct, into proximal structures of the parotid gland owing to increased intraoral pressures. Simultaneous parotid inflammation or infection by oral bacteria produces pneumoparotitis. Dissection of air through the parotid capsule can produce subcutaneous emphysema of the head and neck.1 Given its rarity, descriptions of pneumoparotitis and its treatments are limited to case reports and series, which include patients with unilateral or bilateral pneumoparotid from behavioral and iatrogenic causes.2 It occurs in patients who habitually expire against a closed or resisted oral aperture, such as wind instrumentalists and glass blowers.1,3 Multiple cases have been documented in children with psychiatric disorders.4 It has also been described from use of compressed air during dental procedures and positive pressure associated with anesthesia.2,5