Functional adaptability of temporomandibular joint mechanoreceptors after an increase in the occlusal vertical dimension in rats
Functional adaptability of temporomandibular joint mechanoreceptors after an increase in the occlusal vertical dimension in rats
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DOI：
10.2319/082010-489.1
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发表时间：
2011-05-01
影响因子：
3.4
通讯作者：
Ono, Takashi
中科院分区：
文献类型：
--
作者：
Naito, Satomi;Ishida, Takayoshi;Ono, Takashi
目的：探讨实验诱导的咬合垂直尺寸（iOVD）增加对大鼠颞下颌关节（TMJ）机械感受器功能特征的影响。材料与方法：选用13周龄雄性白化Wistar大鼠60只，分为对照组和iOVD组，每组30只。iOVD组上颌磨牙与下颌磨牙之间的垂直尺寸增加2.0 mm，上颌磨牙上有树脂堆积。被动下颚运动可诱发颞下颌关节机械感受器的单单位活性。在iOVD建立后第1天和第1、3、5、7、9周分别在神经节进行记录。结果：与对照组相比，iOVD组在iOVD后1、3、5周的放电阈值明显降低。第1天、第7周、第9周的放电阈值无显著差异。iOVD组最大瞬时放电频率在iOVD后1、3、5周显著升高，但在第1天、7、9周无显著差异。实验期间，两组的平均发射频率无显著差异。结论：本研究结果提示成年大鼠颞下颌关节机械感受器可能最终适应iOVD。（直角正交。2011;81:453-459）
Objective: To investigate the effects of an experimentally-induced increase in the occlusal vertical dimension (iOVD) on the functional characteristics of temporomandibular joint (TMJ) mechanoreceptors in rats.Materials and Methods: Sixty 13-week-old male albino Wistar rats were divided into control and iOVD groups (30 animals each). The vertical dimension between the maxillary and mandibular molars in the iOVD group was increased by 2.0 mm with a build-up of resin on the maxillary molars. Single-unit activities of TMJ mechanoreceptors were evoked by passive jaw movement. Recording was performed from the gasserian ganglion 1 day and 1, 3, 5, 7, and 9 weeks after the establishment of iOVD.Results: Compared with the control group, the firing threshold was significantly lower at 1, 3, and 5 weeks after iOVD in the iOVD group. There were no significant differences in the firing threshold at 1 day, or 7 or 9 weeks. The maximum instantaneous firing frequency was significantly higher at 1, 3, and 5 weeks after iOVD in the iOVD group, but there were no significant differences at 1 day, or 7 or 9 weeks. There were no significant differences in the average firing frequency during the experimental period.Conclusions: The present study findings suggest that TMJ mechanoreceptors in adult rats may ultimately adapt to iOVD. (Angle Orthod. 2011;81:453-459.)