摆形矫治器与直丝弓矫治器治疗安氏Ⅱ类骨性Ⅰ类错畸形的研究

目的　分析安氏Ⅱ类骨性Ⅰ类错畸形患者经摆形矫治器结合直丝弓矫治器治疗后的牙颌面形态变化,探讨此方法建立正常牙关系的机制。方法　10例接受摆形矫治器结合直丝弓矫治器治疗的安氏Ⅱ类骨性Ⅰ类错患者,分别在治疗前(T1阶段)、摆形矫治器治疗后(T2阶段)及直丝弓矫治结束后(T3阶段)拍摄头颅定位侧位片,对3个阶段牙齿、颌骨及软组织的位置变化进行测量及分析,同时观察上颌第二、三磨牙的位置和萌出情况。结果　摆形矫治器治疗阶段上颌第一、二磨牙远中整体移动并适度远中倾斜,上切牙唇向倾斜,上齿槽座点前移;直丝弓矫治后上颌第一、二磨牙位置与治疗前无明显差异,下齿槽座点和下颌第一磨牙明显前移;上颌第二磨牙萌出顺利。结论　摆形矫治器可使上磨牙明显远中移动,但固定矫治结束后上磨牙前后位置因上颌骨生长和一定程度的支抗丧失而有所复原;Ⅰ类磨牙关系的建立可能是上下磨牙差别移动和颌骨差别生长的综合结果。

A Study on the Module Using Pendulum Combined with Straight Wire Appliance inAngle Class

OBJECTIVE: To investigate morphologic changes of Angle class II and skeletal class I patients during pendulum and straight wire appliances treatment and to analyze the mechanism of this treatment protocol. METHODS: 10 patients with Angle class II and skeletal class I malocclusion were recruited. The lateral cephalometric radiographs were evaluated to determine if there were significant differences among pre-treatment (T1), after molar distalization (T2), and post-treatment (T3) variables including skeletal, dental and soft tissue relationships. RESULTS: Differences between the T1 and T2 means were significant for distal movement and distal angulation of the maxillary molars (P < 0.01), mesial angulation of the maxillary incisors (P < 0.05), mesial movement of the maxilla (P < 0.01) . There were no significant changes between T1 and T3 in respect saggital position and angulation of the maxillary molars (P > 0.05) . Only the mesial movement of lower first molars and upper and lower jaws were significant (P < 0.01) during the whole treatment. No upper second molar impaction was detected after treatment. CONCLUSION: The upper molars distalization could be achieved by pendulum appliance. The class I molar relationship could be obtained by the differential growth of jaws and the differential movement of upper and lower molars.