妊娠对大鼠正畸牙移动的影响实验研究

Research on Rat Orthodontic Tooth Movement in Pregnancy

目的观察妊娠对大鼠正畸牙移动的影响。方法选取48只体重为(250±25)g的Wistar大鼠,并将其分为对照组(非妊娠期)与实验组(妊娠期)。大鼠的上颌中切牙分别用弹簧以30g的力推向远中,在第2d、第7d、第14d观察并记录两个上颌中切牙近中向的距离。随后再利用显微镜观察组织学切片记录破骨细胞的数量,最后对这些数据进行样本t检验。结果两组在第2d、第7d、第14d正畸牙移动的距离相比较没有明显的差异(P>0.05),但是两组的破骨细胞数目存在明显差异(P<0.05),实验(妊娠)组的破骨细胞数目显著降低。结论妊娠期大鼠正畸牙的移动呈轻度减缓,并无统计学意义,但牙体受压侧破骨细胞的变化却有显著的统计学差异。

Objective To explore the affection of pregnancy on rat orthodontic tooth movement. Methods 48 Wistar rats, weighing 250g （±25g）, were selected and randomly divided into 2 groups： pregnancy group and non-pregnancy group; the maxillary central incisors of all the rats in both groups were pulled by spring with a power of 30g to the distal and the mesial distance between the two maxillary central incisors was measured and recorded on the 2^rd, the 7^th and the 14^th day; microscopic observation was made to the histological slices and the number of osteoclast was counted; all the data received t test. Results There existed no obvious difference of the distance in orthodontic tooth movement on the 2＂d, the 7~ and the 14~ day between the 2 groups （P〉0.05） while the numbers of osteoclast in the 2 groups were quite different （P〈0.05）, the number of osteoclast in pregnancy group decreased obviously. Conclusions Rat orthodontic tooth movement in pregnancy is slightly alleviated without statistical significance; the change of osteoclast on the compressed side of the tooth is of great statistical difference.