Sindelar Betty J, Edwards Stan, Herring Susan W
School of Physical Therapy, Grover Center, Rm W295, Ohio University, Athens, OH 45701, USA.
Anat Rec. 2002 Mar 1;266(3):167-76. doi: 10.1002/ar.10050.
Intraoral splints are a commonly used dental treatment for a variety of conditions. Because such splints alter the condyle-disc-fossa relationship, they probably change the loading status of the temporomandibular joint (TMJ), including the TMJ disc. Collagen, a major constituent of the disc, acts to resist tensile loading, and it is presumed that the fiber orientations of the individual disc bands reflect their functional loading. Therefore, the purpose of this study was to examine effects of intraoral splint wear on TMJ morphology in general, and collagen orientation of the intra-articular disc in particular. Young adult, female miniature pigs were divided into three groups: open-bite splint, protrusive-bite splint, and unsplinted control. Splints were worn for 2 months, after which the TMJ discs were harvested for histological examination and stereological analysis, and the skulls were cleaned. Although the splints had no effect on skull dimensions, changes were seen in the TMJs. The discs of the protrusively-splinted group showed an increased thickness of the posterior band (P < 0.015) and minor changes in collagen orientation of the anterior band. The most striking change was the presence of a degenerative osseous defect on the medial side of the mandibular condyle in half of the splinted animals. These results indicate that prolonged splint wear can induce remodeling and even injury of TMJ tissues.
口内夹板是治疗多种口腔疾病常用的牙科治疗手段。由于此类夹板会改变髁突-关节盘-关节窝的关系，它们可能会改变颞下颌关节（TMJ），包括TMJ关节盘的负荷状态。胶原蛋白是关节盘的主要成分，起到抵抗拉伸负荷的作用，据推测，各个关节盘带的纤维方向反映了它们的功能负荷。因此，本研究的目的是检查口内夹板佩戴对TMJ形态的影响，特别是对关节内关节盘胶原蛋白取向的影响。将成年雌性小型猪分为三组：开牙合夹板组、前伸牙合夹板组和无夹板对照组。佩戴夹板2个月后，取出TMJ关节盘进行组织学检查和体视学分析，并清理颅骨。虽然夹板对颅骨尺寸没有影响，但在TMJ中观察到了变化。前伸牙合夹板组的关节盘后带厚度增加（P < 0.015），前带的胶原蛋白取向有轻微变化。最显著的变化是，在一半佩戴夹板的动物中，下颌髁突内侧出现了退行性骨缺损。这些结果表明，长期佩戴夹板会导致TMJ组织重塑甚至损伤。
