上颌前牵引动物模型建立与头影测量分析

摘要

目的:建立模拟临床上颌骨前牵引的动物实验模型.方法:生长发育期的家兔16 只,随机分为实验组和对照组.在距上切牙约1 cm的膜龈联合处安置钛合金钉,做为前颌骨标志点.实验组用自制外置式牵引支架牵引上颌,牵引皮圈连接外置支架和切牙冠套上的牵引钩,向前持续弹性牵引30 d,牵引方向与平面呈向下方30°,力值为3.43 N;对照组仅粘固上切牙套冠,不进行牵引.2 组于实验前、后进行模型测量和头颅定位侧位X线片测量.结果:实验组前颌骨平均前移1.89 mm,而对照组为0.11 mm;头影测量分析:实验组较对照组上颌骨前移,未见明显旋转发生;上下切牙均有轻度的唇倾.2 组下颌骨的变化,无统计学差异.结论:用生长发育期兔和自制外置式牵引装置建立的上颌前牵引的动物模型科学、可靠,可以有效地使上颌骨前移.%Objective: To establish an animal model for research of maxillary protraction. Methods: 16 pubertal rabbits were assigned randomly to 2 groups. Titanium bone markers were fixed on each side of mucogingival junction, 1 cm above incisor teeth. The experimental group underwent maxillary protraction by self-made distraction devices. A down and forward elastic force (about 3.43 N) was exerted for 30 days. Results: In 30 d, the distance of premaxilla movement in the experimental group was 1.89 mm averagely, while that in the control group was only 0.11 mm. Cephalometric analysis indicated that the maxilla of rabbits was moved forward obviously by appliance in the experimental group, and maxilla was not rotated. There was no obvious difference between the control and the experimental groups. Conclusion: Animal model used in this experiment for maxillary protraction is reliable. The appliance can move the rabbits maxilla forward obviously during the maxillary protraction.