Department of Operative Dentistry and Endodontics, College of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, P R China.
Dev Dyn. 2011 Nov;240(11):2466-73. doi: 10.1002/dvdy.22748. Epub 2011 Sep 26.
The mammalian temporomandibular joint (TMJ) develops from two distinct mesenchymal condensations that grow toward each other and ossify through different mechanisms, with the glenoid fossa undergoing intramembranous ossification while the condyle being endochondral in origin. In this study, we used various genetically modified mouse models to investigate tissue interaction between the condyle and glenoid fossa during TMJ formation in mice. We report that either absence or dislocation of the condyle results in an arrested glenoid fossa development. In both cases, glenoid fossa development was initiated, but failed to sustain, and became regressed subsequently. However, condyle development appears to be independent upon the presence of the forming glenoid fossa. In addition, we show that substitution of condyle by Meckel's cartilage is able to sustain glenoid fossa development. These observations suggest that proper signals from the developing condyle or Meckel's cartilage are required to sustain the glenoid fossa development.
哺乳动物颞下颌关节（TMJ）由两个向彼此生长并通过不同机制骨化的独特间充质凝块发育而来，关节窝通过膜内成骨发生，而髁突则起源于软骨内成骨。在这项研究中，我们使用各种基因修饰小鼠模型来研究 TMJ 形成过程中髁突和关节窝之间的组织相互作用。我们报告说，髁突的缺失或脱位都会导致关节窝发育停滞。在这两种情况下，关节窝发育都已经开始，但未能维持，并随后退化。然而，髁突的发育似乎独立于正在形成的关节窝的存在。此外，我们还表明，Meckel 软骨替代髁突能够维持关节窝的发育。这些观察结果表明，发育中的髁突或 Meckel 软骨的适当信号对于维持关节窝的发育是必需的。
