犬切牙压低时牙周膜不同部位微循环变化

目的 研究切牙在压低力作用下牙周膜（PDL）不同部位微循环的变化情况。方法 采用成年雄性杂种犬为实验对象，建立牙齿压低移动动物实验模型，利用计算机图象分析系统定量研究牙齿压低21天后以血管墨汁灌注标记的牙周膜微循环的变化。结果 大小不同的压低力作用于切牙，可引起不同程度的PDL血管化反应：表现为PDL颈部、中部、根尖部微血管数目、管径及体密度均明显增加，仅重力组PDL中部微循环体密度减少，且易观察到透明样变及潜掘性吸收。结论 压低力是引起PDL微循 环发生适应性变化的根本原因，由于PDL的解剖特点，不同部位的微血管均产生了相应的血管化反应。本研究认为犬切牙压低力以30g/cm^2左右最为合适。

Changes Of Microcirculation Of Periodontal Ligament Incident to the Experimental Dog Incisor Intrusion

Objective To study the changes of periodontal ligament's (PDL's) microcirculation in cervical,middle,apical areas incident to the incisor intrusion .Methods An experimental animal model for incisor intrusion was established using adult hybrid dogs and the vasculature was perfused with the ink.Results There are different degrees of vascularization when different magnitude forces was used to intrude the experimental teeth for 21 days. And the activity of the vasculature was increased,Also there are statistical significance in micro-blood vessel number? diameter and volume density between the treatment and control groups,but decreased in the middle PDL's microcirculation in intense force group .Conclusion The intrusive force is the main cause of the adaptive changes of the PDL's microcirculation. Due to the anatomical feature of the PDL,themicrovasculature in different regions of PDL has changed respectively, We think that the optimal intrusive force of the dog's incisor was 30 g/cm 2 or so.