Farrar和McCarty提出,拔除4个双尖牙的正畸治疗,对TMJ结构的稳定性有害。因为在关闭拔牙间隙时,上切牙出现过度反应,造成下颌向后移位。同样,伴有切牙干扰加深覆(牙合)患者,在开闭口过程中,下颌被迫后退,这样导致关节盘的脱位。本研究调查两组病人。一组是37位经过连续正畸治疗的病人,男14名,女23名,年龄10岁～18岁。其中10位 Farrar and McCarty argue that orthodontic removal of the four bicuspid teeth is detrimental to the stability of the TMJ structure. Because in closing the extraction gap, the upper incisors appear overreaction, causing the lower jaw backward shift. Similarly, with incision interference deepen occlusion (occlusion) patients, in the opening and closing process, the mandible was forced to retreat, resulting in disc dislocation. This study investigated two groups of patients. A group of 37 patients after continuous orthodontic treatment, 14 males and 23 females, aged 10 to 18 years. 10 of them