These patients are then treated termly with a mandibular manipulation technique reported by Farrar, which is an effective treatment method to reset the physiological positional relationship between condyle and disc. Neither intermaxillary fixation nor guiding elastics will be used after hand manipulation. Then patients are told to persist in mouth opening training at home everyday. The mouth opening training is performed as follow: patients are told to try to close his mouth in intercuspal position at first, then open their mouth as wide as possible(the reference maximal mouth opening is as wide as the mouth opening after treatment in last time), then closed back to the intercuspal position again. Patients are recommended to follow up at every week at first two months, then every 2 weeks at third months, 6th months, 1 year after first treatment, then yearly afterward. The mandibular manipulation is performed at every follow-up. Meanwhile, the maximal mouth opening (MMO) is recorded before and after hand manipulation treatment. So do the occlusion status, deviation during opening, as well as subjective symptoms of temporomandibular joints. At first moth, 3rd month, 6th month, 1 year, then every year after first treatment, CBCT is performed.