Some mouth restrictions heal on their own and some do not. Generally speaking, if TMJ disorder is the cause of mouth opening restriction, it can be self-healed, but if it is caused by trauma or fracture, it will not be self-healed. The most common cause of limited mouth opening is TMJ disorder, the cause of which is not clear, but is mostly related to anxiety and late-night emotions, therefore, when the anxiety is relieved, the limited mouth opening caused by TMJ dysfunction can be cured by itself. However, if it is caused by trauma or fracture, it is necessary to go to the hospital as soon as possible for treatment. It is necessary to restore the normal position of the joint discs, reset the upper and lower jaws and fixate them to form a correct occlusal relationship, and only after the disease has recovered can the restricted mouth be relieved. Therefore, it depends on the cause whether the mouth opening restriction can be cured by itself or not. The mouth opening restriction caused by TMJ dysfunction can be cured by itself, while the mouth opening restriction caused by other diseases such as bone fracture will not be cured by itself, so it is recommended to seek medical treatment as soon as possible in order to avoid delaying the condition.