Temporomandibular dislocation is a dislocation in which the condyle slips outside the joint fossa beyond the normal limits of joint motion and does not return to its original position on its own. Most TMJ dislocations are anterior to the condyles of the TMJ. The most important clinical manifestation is the inability to close the mouth. Auxiliary examination: X-rays show that the condyle is dislocated in front of the articular tuberosity. It can be divided into: acute dislocation, repeated anterior dislocation, old dislocation; unilateral joint and bilateral joint dislocation can occur. Causes of dislocation: 1. Strong contraction of the extensor pterygoid muscle at the end of large opening, yawning, singing, biting large pieces of food, vomiting, etc. pulls the condyle forward excessively over the articular tuberosity 2. High articular tuberosity or steep anterior bevel of the articular tuberosity, and the chin is subjected to backward external force under open mouth 3. Relaxation 6, muscle dystonia and ligament relaxation in the elderly 7, intellectual abnormalities, mental abnormalities, cerebral palsy, postoperative patients with craniosynostosis First reset the temporomandibular joint: 1, manipulation reset 2, local anesthesia after manipulation reset 3, general anesthesia after manipulation reset 4, general anesthesia after minimally invasive surgical reset Treatment of temporomandibular joint: 1, hyaluronic acid temporomandibular joint cavity injection, gentle efficacy 2, 50% glucose joint cavity injection, only 2.50％ glucose joint cavity injection, can only be used 1-2 times, the drug may cause damage to the articular cartilage 3.Old dislocation treatment manual repositioning difficulties to the main surgical treatment, repeated dislocation after conservative treatment effect is not good also use surgical treatment, surgery chisel flat joint nodules, while considering the revision of the condylar process