牙周膜微血管对水平外力反应的实验研究

目的探讨牙周膜微血管对水平外力的反应。方法以狗为受试对象，使用墨汁灌注，火棉胶包埋，连续切片观察并用图象分析仪进行定量研究，配合对甲基丙烯酸甲酯铸型的扫描电镜观察。结果在狗下颌第四前磨牙施加２００ｇ近中向水平外力２小时后，牵张侧单位牙周膜面积内血管截面积明显大于受压侧，实验组受压侧与对照组同侧比较，差异无显著性。而实验组根颈１／３、根尖１／３的牵张侧与对照组同侧比较，差异有非常显著性。结论牙齿受到短时外力时，牙周膜内微血管的改变对牙周膜的缓冲作用有重要意义。

The responses of the microvasculature of the periodontal ligament to horizontal force

Objective The purpose of this study is to examine the responses of the microvasculature in periodontal ligament(PDL) to horizontal force. Methods Using ink injections and celloidin embed, serial sections were cut, then observed by light micrascope, quantitative analysis was conducted by the picture analysis instrument. Vascular corrosion casts were prepared and examined by scanning electron microscopy. The forth premolars of dogs were pulled by 200g force in a mesial direction for two hours, and the pressure effects in different positions were demonstrated. Results The section area of the microvasculature per unit PDL area is obvious larger on the tension sides than on the pressure sides. There is not an obvious distinction on the pressure sides between the experiment groups and control groups. However, there are clear distinctions in the one third of cervical, and apical segment on the tension sides between the experiment groups and control groups. Conclusion The microvascular changes in PDL had importance to the cushioning effect of PDL when a teeth received a kind of force in a short time.