压低犬牙致牙周膜微循环即期变化的实验研究

Immediate Microcirculation Reaction of Periodontal Ligaments to Experimental Intrusion of Dog Teeth

目的 :研究牙齿在压低移动过程中牙周膜 (PDL)微循环的变化。方法 :任选一侧上第四前磨牙作支抗牙 ,利用带圈压低曲压低第二前磨牙 ,对侧同名牙作对照。采用墨汁灌注技术 ,利用图像分析仪对组织切片进行分析和观察。结果 :10 0g力压低狗上颌第二前磨牙 2h后 ,牙周膜微循环发生了明显改变 ,表现为微血管管径及体密度明显减小 ,而微血管总数未见明显减少 ,亦未引起牙周膜微循环的障碍。结论 :10 0g压低力引起的即期反应为PDL微循环的适应性改变 ,避免牙周膜受到过大负荷 ,减轻组织损伤。

Objective:The purpose of this study is to investigate the immediate microcirculation reaction of periodontal ligaments to experimental intrusion of dog teeth. Methods:The forth premolar was chosen as the anchor tooth to intrude the second premolar using an intrusion circle loop. All tissue sections were observed and analyzed using the ink perfusion technique and an image analysis apparatus.Results:The microvascular pattern of periodontal ligaments was changed after the maxillary second premolar had been intruded for 2 hours with 100g of force. The vascular diameter and volume density diminished, but the vascular number and some parts of the microvasculature, especially capillaries were compressed due to the blood escaping from the periodontal ligament. It showed that the initial effect of 100g of intrusive force caused adaptable changes in the microcirculation of periodontal ligaments, but no significant impediment of blood flow occurred.Conclusion:During the tooth intrusion with 100g of force, a suitable microenvironment was established for the benefit of the survival of periodontal ligaments, which could avoid overloads imposed on the periodontal ligament and decreased the injury of periodontal tissue. It elucidates that the microcirculation of periodontal ligaments plays an important role in the protection of the periodontal tissue, in terms of biological function.