本研究的目的在于评价一组分类患者经固定正畸治疗取得良好关系及牙齿排列后，其下颌切牙的长期稳定性，旨在揭示复发的指征及复发与保持阶段变化因素的关系。78例错的选择指征为：治疗后的模型显示后牙咬会关系良好，前牙覆始覆盖正常，包括非拔牙组及拔干〔两组，所有患 The purpose of this study was to evaluate the long-term stability of the mandibular incisors after a series of patients with orthodontic treatment who had a good relationship with the orthodontic treatment and to reveal the relationship between the signs of recurrence and the factors that affected the relapse and maintenance phase. 78 cases of wrong choice of indications: the model after treatment showed good relationship between the teeth after bite, covering the normal coverage of anterior teeth, including non-extractive group and pull dry 〔both groups, all patients