两种不同前方牵引矫治器矫治替牙早期骨性Ⅲ类错的临床研究

Clinical study of maxillary protraction appliance combined with modified Nance arch and maxillary protraction and rapid palatal expansion in skeletal class Ⅲ malocclusion

目的临床研究改良Nance弓前方牵引矫治器和树脂冠腭开展前方牵引矫治器,观察这两种不同形式的前方牵引对替牙早期骨性Ⅲ类错治疗前后骨骼、牙齿、面型的变化,评价其临床矫治效果。方法选择24例替牙早期骨性Ⅲ类错畸形患者,分别应用改良Nance弓前方牵引矫治器和树脂冠腭开展前方牵引矫治器进行治疗,通过两组X线头颅侧位片进行测量,比较治疗前后软硬组织的变化。结果两个治疗组SNA、ANB、NA-PA、Ptm-A均增大,A点分别前移1.99 mm和2.61 mm,且有统计学意义(P<0.05)。结论两种前方牵引矫治器治疗替牙早期骨性Ⅲ类错均有效,有利于Ⅲ类骨骼的调整,但树脂冠腭开展前方牵引组A点前移较多。

Objective To compare the clinical investigation of maxillary protraction appliance combined with modified Nance arch and maxillary protraction and rapid palatal expansion and evaluate the changes of patients with skeletal class Ⅲ malocclusion in skeletal ,dental, profile and before and after the treatment to evaluate the clinical efficacy. Methods 24 patients with skeletal class Ⅲ malocclusion in mixed dentition were divided into two groups who were treated with maxillary protraction combined with modified Nance arch and maxillary protraction and rapid palatal expansion. Cephalometric radiographs were analyzed to evaluate skeletodental and profile changes before and after treatment. Results SNA and ANB angle, NA-PA, Ptm-A, were increased and subspinales were protracted by 1.99 mm and 2.61 mm. All of the changes were statistically significant （P〈0.05）.Conclusion Both of the maxillary protraction combined with modified Nance arch.andmaxillary protraction and rapid palatal expansion were obviously effective for skeletal class Ⅲ malocclusion in mixed dentition, but maxillary protraction and rapid palatal expansion are much better in protracting subspinales.