Temporomandibular joint dislocation after laryngeal mask airway insertion

Temporomandibular joint (TMJ) dislocation after general anesthesia is not rare. Most victims usually have a past history of TMJ dysfunction or subluxation. It is possible that incomplete TMJ integrity, inadequate articular eminence shape and anesthetic agents that precipitate masticatory muscle hypotonicity are the main factors leading to dislocation. However, some patients suffer from post-anesthesia TMJ dislocation with no connection to prior history. We propose here different mechanisms that may cause TMJ dislocation. TMJ dislocation has been reported after the placement of a laryngeal mask airway for general anesthesia. After reviewing two such cases between August 2004 and July 2007, we found that some iatrogenic factors might intensify the risk of TMJ dislocation. The clinical implications of these findings are discussed herein.