氦-氖激光对兔正畸牙移动牙周组织中基质金属蛋白酶-9表达的影响

目的　研究He Ne激光照射对兔实验性牙移动牙周组织中基质金属蛋白酶 9(MMP 9)表达的影响 ,探讨He Ne激光局部照射对促进正畸牙齿移动及牙周组织改建的可行性。方法　 3 0只大耳白兔 ,随机分为 6组 ,每组 5只 ,其中实验动物右侧为照射侧 ,左侧为对照侧。各组动物分别经正畸实验装置给予持续 1,3 ,5 ,7,14及 2 1d的加力处理 ,同时实验动物右侧局部牙周组织给予He Ne激光照射 ,左侧则不进行特殊处理。各组实验动物分别于实验结束后处死 ,对实验样本进行MMP 9免疫组织化学染色、图像分析 ,观察兔实验性牙移动牙周组织中MMP 9表达与分布的变化 ,并进行统计学分析。结果　He Ne激光照射侧压力区与张力区MMP 9的表达增强现象均较对照侧出现得早 ,且峰值亦较对照侧高。张力区兔牙周组织中MMP 9表达灰度分析表明 ,术后第 5 ,7天时 ,照射侧与对照侧间差异有显著性意义 (P <0 .0 5 ) ,压力区兔牙周组织中MMP 9表达灰度分析表明 ,术后第 3 ,5 ,7天时 ,照射侧与对照侧间差异有显著性意义 (P <0 .0 5或0 .0 1)。结论　He Ne激光照射增强了兔正畸牙周组织中MMP 9的表达 ,提示He Ne激光照射促进了正畸牙移动过程中的血管化反应及骨改建过程。

Effects of He-Ne irradiation on matrix metalloproteinases-9 expression during experimental tooth movement in rabbits

Objective To explore the feasibility of He-Ne laser irradiation in promoting orthodontic tooth movement and periodontal remodeling through observing the effect of low power laser on the expression and distribution of matrix metalloproteinases- 9(MMP- 9) during orthodontic tooth movement in rabbit. Methods Thirty rabbits were divided into 1d,3d,5d,7d,14d and 21d groups, each group were given a coil spring connected to the maxillary upper first molar to the upper incisor and fixed bilaterally by a ligature wire and set force to 80g. He-Ne laser irradiation was performed on the right side of the orthodontic tooth, and the left side served as control. Radiation time ranged from 1 day to 5 days, once a day, 15min each time. All of the tissue sections were proceeded with MMP- 9 immunohistochemical staining. MMP- 9 average gray scale in periodontal tissue of the orthodontic teeth was analyzed by a Computer Image Analyzing System. Results The expression level of MMP- 9 increased earlier and lasted for a longer time in the compression and tension area on the side of irradiation by He-Ne laser as compared to those on the control side. There was significant difference between the irradiation side and the control side in terms of the MMP- 9 expression gray scale in the tension zones at 5 and 7 days post-operation, and in the pressure zones at 3,5,7 day post-operation. Conclusion During the movement of orthodontic teeth, local irradiation with He-Ne laser could increase the expression of MMP-9. It was suggested that the irradiation with low power laser accelerate blood vessel and bone remodeling.