Does hypersensitive teeth show pulp inflammation?

ABSTRACT Objective: This study investigated the presence of inflammatory response in the dental pulp of rats showing hypersensitive dentin, induced by erosive episodes. Methods: Sixteen Wistar rats were fed with commercial sucrose-free pellet diet for 12 hours; whereas the food was removed during the remainder of the day, and the animals received mineral water or a lemon-based sucrose-free soft drink, according to the group to which they belonged. Eight animals consumed the soft drink to induce hypersensitivity, while the other 8 animals received mineral water (control). After six weeks, the animals were euthanized, the mandible was removed and subjected to a median incision in the sagittal plane, to obtain right and left hemimandibles. The slides stained with hematoxylin-eosin were analyzed using light microscopy. Results: Histological evaluation of the control and experimental groups revealed no inflammatory process in the pulp tissue, and the presence of inflammatory cells, such as lymphocytes, plasma cells, eosinophils and macrophages, was not observed. In addition, there was no edema or dilated and congested blood vessels. The Mann-Whitney test showed no significant difference (p = 1.000) between the experimental and the control groups. Conclusion: In the animal model used, dentin hypersensitivity does not trigger dental pulp inflammatory response.

摘要 研究目的：本研究旨在探究由侵蚀性刺激事件诱导的牙本质敏感（dentin hypersensitivity）大鼠牙髓（dental pulp）中炎症反应的存在情况。研究方法：将16只Wistar大鼠置于每日仅12小时进食商业无蔗糖颗粒饲料的饲养条件下，其余时段移除饲料；根据分组情况，大鼠可饮用矿泉水或柠檬味无蔗糖软饮。其中8只大鼠饮用该软饮以诱导牙本质敏感，其余8只饮用矿泉水作为对照组。饲养6周后，对大鼠实施安乐死，取下下颌骨并沿矢状面（sagittal plane）行正中切口，获取左右半下颌骨。采用光学显微镜对苏木精-伊红（hematoxylin-eosin）染色的组织切片进行分析。研究结果：对照组与实验组的组织学评估均未发现牙髓组织存在炎症进程，亦未观察到淋巴细胞（lymphocytes）、浆细胞（plasma cells）、嗜酸性粒细胞（eosinophils）及巨噬细胞（macrophages）等炎症细胞的存在。此外，未出现水肿或血管扩张充血的情况。曼-惠特尼检验（Mann-Whitney test）结果显示，实验组与对照组间无显著统计学差异（p=1.000）。研究结论：在本研究所采用的动物模型中，牙本质敏感并不会引发牙髓炎症反应。