Abstract:

Objective    To evaluate the treatment effects of rapid maxillary expansion and maxillary protraction and straight wire appliance technology on patients with skeletal class Ⅲ malocclusion in early permanent dentition. Methods    A total of 15 skeletal class Ⅲ patients were chosen based on the principle of maxillary retrusion in early permanent dentition and treated by straight wire appliance technology combined with maxillary protraction and rapid maxillary expansion. Results    A total of After treatment the profile improved evidently，and the normal molar relationship，overjet and overbite were established. The cephalometric analysis showed that SNA increased by（2.87 ± 1.08）°，SNB decreased by（0.61 ± 0.8）° and ANB increased by（3.47 ± 1.05）°. SN/MP increased by（2.17 ± 1.34）°，OP/FH increased by（2.97 ± 0.29）°，mandible rotated clockward and propile improved.  U1/SN increased by（5.09 ± 3.43）°，the upper incisors tipped labially，and L1/MP decreased by （2.29 ± 3.02）°. Conclusion    Straight wire appliance technology with maxillary protraction and rapid maxillary expansion is helpful and specific in treating skeletal class Ⅲ patients with maxillary retrusion in early permanent dentition.

Key words: rapid maxillary expansion and maxillary protraction, straight wire appliance technology, skeletal class Ⅲ malocclusion, early permanent dentition

摘要：

目的    探讨上颌扩弓前方牵引配合直丝弓矫治技术对恒牙早期骨性Ⅲ类错牙合畸形的矫治效果。方法    采用上颌扩弓前方牵引矫治器配合直丝弓矫治技术，对2010—2015年大连市口腔医院正畸科15例恒牙早期骨性Ⅲ类错牙合患者进行代偿性治疗，并对其治疗前后头颅定位侧位片进行测量分析。结果    15例患者治疗后面型改善，磨牙中性关系，前牙覆牙合覆盖正常。SNA角增加（2.87 ± 1.08）°，SNB角减小（0.61 ± 0.8）°，ANB角增加（3.47 ± 1.05）°，SN/MP增加（2.17 ± 1.34）°，OP/FH增加（2.97 ± 0.29）°，U1/SN增加（5.09 ± 3.43）°，L1/MP减小（2.29 ± 3.02）°，结论    上颌扩弓前方牵引配合直丝弓矫治技术可有效治疗恒牙早期中轻度骨性Ⅲ类错牙合畸形。

关键词: 上颌扩弓前方牵引, 直丝弓矫治技术, 骨性Ⅲ类错牙合畸形, 恒牙早期