Automobilization intervention and exercise for temporomandibular joint open lock

Temporomandibular joint disorders (TMDs) are common and may cause temporomandibular joint (TMJ) locking, pain, and disability. Evidence supports use of manual therapy and exercise for treatment of TMDs including disk displacement limiting full mouth opening, TMJ 'closed lock'. Only limited case studies describe management of TMJ 'open lock', a condition due to posterior disk displacement (PDD) or TMJ anterior dislocation (TMJ-AD). Reported treatment for open lock includes splinting and intraoral joint manipulation. This case report describes a novel extraoral automobilization using the mandibular elevator muscles to treat TMJ open lock in a 22-year-old male after intraoral joint mobilization failed. The exercise program used to restore neuromuscular control for post-reduction management is described. Short term results of automobilization were excellent with restored ability to swallow, speak normally, and achieve occlusion. Long term results at 14 months were good: the patient was pain-free, could swallow and speak normally, had no recurrence of TMJ locking, and minimal disability. Limited right lateral excursion range and left mandibular deviation during mouth opening indicated possible persistence of PDD. This case suggests that mandibular elevator automobilization and masticatory muscle exercise may be useful to treat TMJ open lock and should be considered to treat PDD and TMJ-AD.