What is Difficulty Opening the Mouth? The normal degree of mouth opening is equivalent to the width of the index, middle and ring fingers when they are brought together. Clinically, there are many diseases that can cause mouth opening restriction, it is generally believed that if the patient opens his mouth to accommodate only two fingers, it is known as mild mouth opening restriction; if the degree of mouth opening can only accommodate one finger, it is known as moderate mouth opening restriction; if even one finger can not be accommodated after opening the mouth, it is known as dental clenching. Then how to diagnose the symptoms of dysphagia? Symptoms of diagnosis: 1, otogenic diseases Boils on the external auditory canal and inflammation of the middle ear also often radiate to the joint area pain and affect the opening of the mouth and chewing, a careful otological examination when it is not difficult to distinguish. 2, the stenosis long syndrome in addition to swallowing pharyngeal pain and sensory abnormalities, often in the opening, chewing can be caused by the condylar process of the posterior region of the pain and the joints of the posterior region, the posterior region of the ear and the neck involved in pain. x-ray examination, easy to confirm the diagnosis. 3, hysterical dental clenching hysterical dental clenching, such as and the whole body other muscle spasm or convulsive symptoms, the diagnosis is relatively easy. This disease mostly occurs in young women, previous history of hysteria, have unique character traits, usually at the onset of mental factors, and then suddenly occurred in the difficulty of opening the mouth or clenching the teeth. This disease with verbal suggestion or indirect suggestion (with other therapeutic method combined with verbal suggestion) can often work. 4, tetanus teeth and joints tightly closed tetanus is caused by tetanus bacillus an acute specific infection characterized by paroxysmal spasms and tense contractions. Due to the initial symptoms can be manifested as difficulty in opening or closed teeth to the stomatology department, should be identified with temporomandibular joint disorder syndrome, so as to avoid delaying the time of early treatment. Tetanus clenching is usually associated with a history of trauma. The spasm usually starts from the masticatory muscles, firstly, the masticatory muscles are a little bit tense, that is, the patient feels restricted in opening; followed by the emergence of tonic spasm of clenched teeth; at the same time, it also causes the tightening of the expression muscles to make the facial expression special, forming the “bitter smile” face and may be accompanied by facial muscle twitching.