大鼠实验性牙髓炎的组织病理学观察

The histopathological study on the pulpal response after experimental pulpal exposure in rats

目的采用单纯开放法建立大鼠实验性牙髓炎模型,观察大鼠牙髓在口腔自然菌群感染下的组织病理学反应。方法选择SD大鼠16只,1只为空白对照,另15只右侧上颌第一、第二磨牙合面开髓,每组3只分别与术后即刻1、天、3天、5天、7天处死,取牙齿标本,经固定、脱钙、切片、HE染色光镜观察牙髓组织的病理变化。结果术后1天穿髓点下方有大量中性粒细胞浸润,表现为急性浆液性炎症反应,经过3天、5天、7天牙髓炎症反应逐渐加重,牙髓血管充血、成牙本质细胞空泡性变、自冠髓至根髓逐渐坏死,在根管壁可见少量修复性牙本质形成。结论单纯开放法可观察到牙髓炎的自然发展过程,是建立大鼠实验性牙髓炎动物模型的方法之一。

Objective To establish model of pulpitis with pulpal exposure of rats and to investigate the histopathological changes of pulps. Methods Fifteen SD mrs were received a pulpal exposure in the fight maxillary first molar and right maxillary second molar. Three animals of each group were sacrificed after exposure immediately, 1st,3rd,5th,7th day.The teeth of each animal were fixed,decalcified and section serially.The section was stained with HE and evaluated pathological changes under a light microscope. Results Histologically, the acute serious inflammation was observed in the pulps and infiltration of inflammatory cells occurred in their exposure sites after 1 days. Inflammation reaction of pulp gradually serious, pulp hyperemia, vacuolar degeneration of the odontoblastic layer and the pulpal necrosis observed gradually from the coronal pulps to the radicular pulps after periods of 3 days, 5 days, 7 days. Reparative dentine was examined in the mot canal wall. Conclusion Pulpal exiposure can find the natural development of pulpitis, and it is one of the methods to establish the model of rat experimental pulpitis.