骨支抗摆式矫治器治疗安氏Ⅱ类错[牙合]的临床效果

Clinical effect of bone-anchored pendulum in treatment for class Ⅱ malocclusion

目的探讨骨支抗摆式矫治器治疗安氏Ⅱ类错[牙合]的临床效果。方法2014年1月至2016年12月,广州市妇女儿童医疗中心口腔科选择符合摆式矫治器治疗适应证患者12例,每例患者在硬腭前部放置2个种植钉,位置在切牙孔后6~9 mm,离开腭中,停止加力。每例患者在移动磨牙前(T1)、磨牙移动到位时(T2),皆拍摄头颅侧位片。对每例患者各个阶段头颅侧位片进行测量。结果矫治器加力时间7个月,磨牙基本到位。治疗后,第1磨牙远中移动7.07 mm,远中旋转9.93°,差异有统计学意义(P<0.05)。第2、第1双尖牙分别远中移动5.44 mm和4.09 mm,远中旋转5.22°和3.95°,治疗前后改变比较,差异有统计学意义(P<0.05)。切牙腭向倾斜1.66°,切缘腭向移动0.93 mm。结论骨支抗摆式矫治器通过用微种植钉,可有效推动上颌磨牙向远中移动,不会造成双尖牙近中移动和前牙唇倾,相比传统摆式矫治器更有优势。

Objective To study the clinical effect of bone-anchored pendulum in treatment for class Ⅱ malocclusion. Methods Twelve patients treated by bone-anchored pendulum were chosen. In each patient, two microscrews were inserted in the anterior paramedian region of the median palatal suture, 6-9 mm posterior to the incisive foramen and 3–6 mm lateral to the median line. Pendulum that based on the microscrews was used to distalize maxillary first molar, and the force applied was 250 g. Skeletal and dental changes were measured on cephalograms before (T1) and after (T2) distalization. Results Class Ⅰ molar relationship had been obtained 7 month after distalization. The average distal movement of the maxillary first molars was 7.07 mm, and the inclination was 9.93°. The second premolars were distalized an average of 5.44 mm with inclinations of 5.22°. The first premolars were distalized an average of 4.09 mm with inclinations of 3.95°. The maxillary anterior teeth were retruded 0.93 mm and palatally inclined 1.66°. There was statistical difference in that change. Conclusions By the use of microscrew, pendulum can distalize maxillary molar effectively without mesial movement of premolar and labial movement of incisor, and no loss of dental anchorage is observed during the distal movement.