钕铁硼永磁体与双阻板矫治器矫治AngleⅢ类错[牙合]

目的：观察双阻板矫治器基础上使用钕铁硼永磁体矫治AngleⅢ类错牙合]的效果。方法：15例替牙及恒牙早期AngleⅢ类错牙合]畸形患者，男6例，女9例。年龄9-13岁，平均11.25岁。在双阻板矫治器的上下阻板安放第三代高磁能积稀土永磁体钕铁硼，矫治过程中磁块间距的增加说明疗效，间距加1mm以上考虑加力。治疗前后头颅侧位片及常规头影方法进行分析。结果：与矫治前相比，矫治后ANB角，Ao—Bo距，NA—PA角均增大，差异有统计学意义（P〈0.01）。SNB角减小，差异有统计学意义（P〈0．01）。结论：磁力双阻板矫治器克服了传统矫形装置的缺点，从而能获得持续的矫形力，磁力调整易于控制，便于临床开展。

Nd-Fe-B Magnets and Twin-black Appliance Used in Treating Class Ⅲ Malocclusion

Objective： To evaluate the effect of coordinating functions between twin-block appliance and NdFeB magnet on treatment of skeletal class Ⅲ malocclusion. Methods： A total of 15 cases of patients （6 boys and 9 girls, with age ranging form 9 to 13 years, mean age 11.25 years ） with skeletal Class Ⅲ malocclusion in mixed dentition and early permanent dentition period were included in this study. We put the NdFeB magnet on the up- and down- baffles of the twin-block appliance. Good curative effect could be achieved if the spacing between magnetic pieces were increasing. When the space increase is more than lmm, the magnetic force needs to be strengthened. Lateral cephalometric radiographs were traced manually and subjected to the statistics analysis before and after treatment. Results： The class III dentofacial profile significantly improved, and ideal posttreatment larger ANB angles, Ao-Bo spurs, NA-PA angles （p〈0.01） and smaller SNB angles （p〈0.01 ） were achieved. Conclusion： The twin-block magnetic appliance surmounts many disadvantages of the traditional orthopedic appliance due to the persistent orthopedic force and the capable of easily adjusting the magnetic force, and the clinical applications are easy to carry out.