Yawning and rattling of the bones should be a sign of temporomandibular joint disorder syndrome. There are many types of temporomandibular joint disorder syndrome, yawning bone ringing is the pterygoid muscle hyperfunction, the normal temporomandibular joint consists of the joint head, articular surface, and the articular disk between them, and the surrounding joint capsule, articular ligament composition. The joint head carries the articular disk during opening, moves forward and downward along the posterior slope of the articular tubercle, stops moving at the very bottom of the articular tubercle to close the mouth, and then returns to the articular fossa along the posterior slope of the articular tubercle. If the extrapterygoid muscles are hyperfunctional, there is no end to the movement of the joint head to the underside of the articular tubercle. It will also move along the anterior oblique of the articular tubercle and slightly forward and upward at the time of maximal opening, when there is a crisp pop. And also during the closed mouth movement the joint head strikes the anterior bevel of the articular node first, then goes underneath the articular node, and then returns to the joint fossa, where a single crisp pop also occurs.