内毒素脂多糖刺激大鼠牙髓的组织病理学反应

The histopathological study on the pulpal response to application of Lipopolysaccharide(LPS) to the pulps of rats

目的：研究牙髓在厌氧菌内毒素侵袭过程中的防御机制，建立内毒素性牙髓炎症模型。方法：采用大肠杆菌内毒素脂多糖（ＬＰＳ）涂布大鼠磨牙牙髓的方法，观察牙髓在ＬＰＳ刺激后的组织病理学反应。结果：浓度为５ｍｇ／ｍｌ的ＬＰＳ处理穿髓点处牙髓３０ｍｉｎ，牙髓早期表现为急性化脓性炎症组织像，１周后炎症扩散至大部分冠髓。至第５周，冠髓及大部分根髓坏死，而对照组牙髓内已无炎细胞浸润。结论：本组结果提示尽管牙髓组织有较强的自身防御、修复能力，但如不及时去除抗原物质，最终仍会导致牙髓坏死。

Aim: To investigate the defensive mechanism of pulpal response to the invading endotoxin of anaerobic bacteria, and to establish a model of endotoxic pulpitis. Methods: The pulps of rat molars were stimulated with LPS to observe the histopathological changes of pulps. Results: The acute suppurative inflammation was observed initially in the pulps after their exposure sites were treated with 5mg/ml LPS for 30min. After 1 week, here was diffused inflammation in many of the coronal pulps. Up to 5 weeks, there was pulpal necrosis occurred in the coronal pulps and most part of the radicular pulps and no infiltration of inflammatory cells occurred in the pulps in controlled group. Conclusions: If the antigenic materials were not removed in time, the pulps would eventually be involved in necrosis in spite of the certain capacity of pulped self-reparation.