颌面部撞击伤致牙髓间接损伤的实验研究

An experimental study on indirect trauma of dental pulp caused by maxillofacial impact injury

目的探讨颌面部撞击伤导致的牙髓间接损伤的特点。方法 18只实验犬随机分为6组,以质量0.26 kg的铁质帽状圆柱体撞击致伤犬右下颌骨体部,但不直接伤及牙齿;分别于伤后6、24 h,3、7 d,24、周处死动物,分别观察右下颌第四前磨牙、第二前磨牙及左下颌第二前磨牙牙髓的组织病理学和超微结构变化。结果右下颌第四前磨牙牙髓损伤较重,但最终没有发生不可逆性坏死改变;右下颌第二前磨牙牙髓损伤相对较轻;左下颌第二前磨牙牙髓仅有轻微的一过性损伤。结论犬下颌骨撞击伤导致的牙髓间接损伤损伤范围较广,损伤程度随着距离的增加而迅速递减,损伤一般是可逆的。

Objective To analysis the characteristics of indirect dental pulp injury caused by impact injury of mandible.Methods Eighteen dogs were divided equally into six groups with random allocation.The right mandible of each dog was impacted by a cylindroid irony cap weighted 0.26kg,but teeth were not injured directly.Then,the animals were killed at 6h、24h,3d、7d,2 and 4weeks later,respectively,and the histopathologic and ultrastructural changes of dental pulp of the fourth premolar of right mandible,the second premolar of right mandible and the second premolar of left mandible were investigated.Results Dental pulp of the fourth premolar of right mandible was injured rather severely,but irreversible necrosis did not occur in the end.Dental pulp of the second premolar of right mandible was injured less severely.Dental pulp of the second premolar of left mandible was injured mildly and temporarily.Conclusion In the indirect injury of dental pulp caused by maxillofacial impact injury,the injured area is relatively extensive.The effect of the trauma decreases progressively and sharply as the distance to the impact site increases.The injuries are generally reversibly.