Abstract:

Objective: To evaluate the differences in nerve fiber density and the percentage of Piezo-positive nerve fibers between peri-implant and periodontal tissues. Methods: Primary trigeminal ganglion neurons were isolated from male Sprague-Dawley (SD) rats, and the expression of Piezo ion channels in these neurons was confirmed by immunofluorescence staining, real-time quantitative polymerase chain reaction (RT-qPCR) and gel electrophoresis. Subsequently, a dental implant model was established in the maxillary first molar region of male SD rats. One month after osseointegration, the rats were euthanized, and the maxillae were collected. Hematoxylin-eosin (HE) staining and immunofluorescence staining were employed to analyze and compare the differences in nerve fiber density and the percentage of Piezo-positive nerve fibers across four regions between the peri-implant tissues and the periodontal tissues. Results: Immunofluorescence staining, RT-qPCR and gel electrophoresis results demonstrated that both Piezo 1 and Piezo 2 ion channels were expressed in trigeminal ganglion neurons. In both peri-implant tissues and periodontal tissues, the gingival and apical regions exhibited a higher density of nerve fibers, with similar nerve fiber density observed in the gingival region between the two tissue types. In the middle region, the density of nerve fibers in the periodontal ligament was significantly higher than that in the bone surrounding the implant, while no significant differences were found in the gingival, apical and coronal regions. In the gingival region, there were no notable differences in the percentage of Piezo 1- and Piezo 2-positive nerve fibers among the groups. In the coronal and middle root regions, the percentage of Piezo 1- and Piezo 2-positive nerve fibers in the periodontal ligament was significantly higher than that in the alveolar bone directly adjacent to the implant. Conclusion: In the coronal and middle root regions, the percentage of Piezo-positive nerve fibers in the periodontal ligament was significantly higher than that in the alveolar bone directly adjacent to the implant.

Key words: Piezo ion channels, nerve fibers, implant, tooth

摘要：

目的：评估种植体周围组织和牙周组织中Piezo阳性神经纤维的分布差异。方法：采用实时定量聚合酶链反应（real-time quantitative polymerase chain reaction，RT-qPCR）及凝胶电泳实验检测SD大鼠原代三叉神经细胞中Piezo离子通道的表达。基于雄性SD大鼠构建上颌第一磨牙区种植模型。在骨结合1个月后，处死大鼠并收集上颌骨，通过苏木精-伊红（hematoxylin-eosin，HE）染色和免疫荧光染色分析比较种植体周组织和牙周组织4个区域内神经纤维密度和Piezo阳性神经纤维百分比差异。结果：免疫荧光染色、RT-qPCR及凝胶电泳结果表明，Piezo 1和Piezo 2离子通道均在三叉神经细胞中表达。在种植体周组织和牙周组织中，牙龈区与根尖区均呈现较高的神经纤维密度，在牙龈区，二者的神经纤维密度相近。在根中区，牙周韧带中神经纤维的密度明显高于种植体外围牙槽骨，而在牙龈区、根尖区和牙冠区，三者无明显差异。在牙龈区，各组Piezo 1、Piezo 2阳性神经纤维的百分比无明显差异。在牙冠区和根中区，牙周韧带中Piezo 1、Piezo 2阳性神经纤维百分比明显高于直接接触种植体牙槽骨中Piezo的阳性神经纤维百分比。结论：在牙冠区和根中区，牙周韧带中Piezo阳性神经纤维百分比明显高于直接接触种植体牙槽骨中的Piezo阳性神经纤维百分比。

关键词: Piezo离子通道, 神经纤维, 种植体, 牙齿