The action of opening the mouth wide is mainly accomplished by the temporomandibular joint (TMJ), in which the TMJ ligaments are stretched and the mandible is shifted backward and downward to accomplish this action. The TMJ can degenerate due to laughter, trauma, inflammation, poor chewing habits (often eating hard objects or chewing on one side of the teeth), manifesting itself as dysfunction, and in severe cases dislocation (commonly known as dropping of the jaw) can occur. When temporomandibular dysfunction occurs, the joints will pop when the mouth is opened. Treatment: The first point is to limit the activities of the temporomandibular joints, avoid frequent opening of the mouth and chewing hard objects and other bad habits, avoid laughing, if the symptoms are serious, you can apply local hot compresses to relieve the congestion of the joint ligaments and joint capsule, you can try acupuncture, and if necessary, you can apply a bandage to limit the immobilization of the lower jaw.