Mechanical loading leads to osteoarthritis-like changes in the hypofunctional temporomandibular joint in rats
Mechanical loading leads to osteoarthritis-like changes in the hypofunctional temporomandibular joint in rats
复制标题
DOI：
10.1016/j.archoralbio.2014.08.010
复制
发表时间：
2014-12-01
影响因子：
3
通讯作者：
Ono, Takashi
中科院分区：
文献类型：
--
作者：
Ikeda, Yuhei;Yonemitsu, Ikuo;Ono, Takashi
目的：颞下颌关节（TMJ）功能低下继发于生长期的流质饮食，导致形态发育不良。然而，很少有研究评估的结果，机械负荷发育不良的颞下颌关节。本研究探讨是否TMJ功能减退的大鼠骨关节炎（OA）的变化时，暴露于mechanical loading.Design：雄性21日龄Wistar大鼠被分为四组。第一组（C）作为对照。在第二组（W）中，从63日龄开始，通过连续稳定张口（3 h/d，持续5d）对TMJ施加机械负荷。使用开颌装置，用钴铬（Co-Cr）丝（φ：0.9 mm）将下颌骨保持在最大张口位置。C组和W组均接受正常硬质饮食。第三组（L）和第四组（LW）饲喂流质饲料，LW组进行与W组相同的负荷。结果：LW组髁突上级和后部骨体积分数、骨小梁厚度和骨小梁数量明显减少，骨小梁间距明显增加。MMP-13免疫阳性细胞的比例显著高于其他组。OA样的变化也被观察到，包括软骨厚度减少，在软骨细胞层的不规则性，和无细胞areas.Conclusions：TMJ功能减退的大鼠很可能会导致OA样的变化时，暴露于机械负荷。(C)2014爱思唯尔有限公司版权所有。
Objectives: Temporomandibular joint (TMJ) hypofunction secondary to feeding a liquid diet in the growing period leads to morphological hypoplasia. However, few studies have evaluated the results of mechanical loading on the hypoplastic TMJ. This study investigated whether TMJ hypofunction in rats causes osteoarthritis (OA)-like changes when exposed to mechanical loading.Design: Male 21-day-old Wistar rats were divided into four groups. The first group (C) served as the control. In the second group (W), mechanical loading was applied to the TMJ by continuous steady mouth opening (3 h/day for 5 days) from 63 days of age. A jaw-opening device was used to hold the mandible open in the maximal mouth-opening position with a cobalt chromium (Co-Cr) wire (phi: 0.9 mm). Groups C and W both received a normal hard diet. The third group (L) and fourth group (LW) were fed a liquid diet and group LW were subjected to the same loading as group W. We evaluated the TMJ using micro-CT, toluidine blue staining and immunohistochemistry of matrix metalloproteinase (MMP)-13.Results: In group LW in the superior and posterior regions of the condyle, bone volume fraction, trabecular thickness and trabecular number were significantly decreased and trabecular spacing was significantly increased. The ratio of MMP-13 immunopositive cells was significantly higher than in the other groups. OA-like changes were also observed, including reduced thickness of the cartilage, irregularities in the chondrocytic layer, and cell-free areas.Conclusions: TMJ hypofunction in rats is likely to lead to OA-like changes when exposed to mechanical loading. (C) 2014 Elsevier Ltd. All rights reserved.