Department of Orthodontics, Faculty of Dentistry, Atatürk University, Erzurum, Turkey.
Eur J Orthod. 2010 Apr;32(2):154-8. doi: 10.1093/ejo/cjp083. Epub 2009 Sep 9.
The aim of the present study was to investigate the effects of two different force levels on the amount of total and daily tooth movement in rabbits and to determine whether any increase in tooth movement is equal to the increase in force. Forces of approximately 20 (group I) and 60 (group II) g (19.6 and 58.8 cN) were applied to the upper central incisors of 25 young adult (14 weeks of age) New Zealand female rabbits. The distance between the incisors was measured daily from the mid-levels of the crowns using a digital calliper for 20 days. Analysis of variance and Bonferroni multiple range test were used for statistical analyses. The distance between the teeth in group II was significantly greater than that in group I during the first 3 days. Between days 4 and 14, no significant difference was observed. During the last 6 days, except for day 19, tooth movement in group II again increased, resulting in the distance between the teeth being greater in group II. The mean total opening was 3.98 +/- 0.59 mm in group I and 4.82 +/- 0.82 mm in group II, and the mean difference was approximately 0.8 mm. The results of this study show that there was a close relationship between tooth movement and force magnitude. However, higher forces did not produce force-equal tooth movements.
本研究旨在探讨两种不同力水平对上颌中切牙总牙移动量和日牙移动量的影响，并确定牙移动量的任何增加是否与力的增加成正比。对 25 只年轻成年（14 周龄）新西兰雌性兔的上颌中切牙施加约 20（组 I）和 60（组 II）g（19.6 和 58.8 cN）的力。使用数字卡尺从牙冠的中水平每天测量切牙之间的距离，持续 20 天。采用方差分析和 Bonferroni 多重范围检验进行统计学分析。在第 1 天到第 3 天，组 II 的牙齿间距明显大于组 I。在第 4 天到第 14 天，没有观察到显著差异。在最后 6 天，除第 19 天外，组 II 的牙齿移动再次增加，导致组 II 的牙齿间距更大。组 I 的平均总开口为 3.98 +/- 0.59mm，组 II 的平均总开口为 4.82 +/- 0.82mm，平均差异约为 0.8mm。本研究结果表明，牙移动与力大小之间存在密切关系。然而，较高的力并没有产生与力相等的牙齿移动。
