目的评价自锁矫治器和直丝弓矫治器非拔牙矫治前后对安氏Ⅰ类错牙合患者牙弓形态的影响。方法选择2007—2010年沈阳市口腔医院正畸门诊骨性I类、安氏I类错牙合畸形患者40例,采用SmartClipTM自锁矫治器(自锁组)和MBT直丝弓矫治器(MBT组)矫治,各20例。制取矫治前后模型,利用MICROTEKi800型扫描仪扫描入计算机中,利用Photoshop软件对模型上的15个标志点进行定点,使用E-ruler软件对每个模型上各标志点的横、纵坐标值及尖牙宽度、磨牙宽度、尖牙深度、磨牙深度进行测量比较。结果自锁组和MBT组矫治后的牙弓宽度及深度均较矫治前增加,差异均有统计学意义(均P<0.05),但两组矫治后的尖牙宽度、磨牙宽度、尖牙深度、磨牙深度的增加量比较,差异均无统计学意义(均P>0.05)。结论 SmartClipTM自锁托槽矫治器与MBT直丝弓矫治器同样对牙弓有较好扩弓作用,可广泛应用于临床。 Objective To evaluate the effect of self-locking appliance and straight-wire appliance on dental arch before and after non-extractive treatment. Methods Forty patients with skeletal Class I and Class I malocclusions undergoing orthodontic treatment at Shenyang Stomatological Hospital from 2007 to 2010 were selected. The patients were treated with SmartClipTM self-locking appliance (self-locking group) and MBT straight appliance (MBT Group) correction, each 20 cases. The model before and after orthodontic treatment was prepared and scanned into the computer with the MICROTEKi800 scanner. The Photoshop software was used to locate the 15 markers on the model. The horizontal and vertical values ​​of each marker on each model were calculated using E-ruler software. Canine width, molar width, canine depth, molar depth measurements were compared. Results The arch width and depth of the arch after self-locking group and MBT group were significantly higher than those before correction (all P <0.05). However, the canine width, molars width, canine depth , There was no significant difference in the increase of molar depth between the two groups (all P> 0.05). Conclusion SmartClipTM self-ligating brackets appliance and MBT straight wire appliance also have good expansion of dental arch, which can be widely used in clinic.