Bosshardt Dieter D, Sculean Anton, Windisch Péter, Pjetursson Bjarni E, Lang Niklaus P
Department of Periodontology and Fixed Prosthodontics, School of Dental Medicine, University of Berne, Berne, Switzerland.
J Periodontal Res. 2005 Apr;40(2):158-67. doi: 10.1111/j.1600-0765.2005.00785.x.
Enamel matrix-derived proteins (EMD) are thought to trigger the formation of acellular extrinsic fibre cementum (AEFC), while other reports indicate that EMD may have osteogenic potential. The aim of the present study was to characterize the tissues developing on the root surface following application of EMD.
Twelve human periodontitis-affected teeth, scheduled for extraction, were treated with EMD. Two to 6 weeks later, the teeth were extracted, demineralized and processed for embedding in acrylic and epoxy resins. New tissue formation was analysed by light and transmission electron microscopy.
New tissue formation on the root was observed in the notch and on both scaled and unscaled root surfaces distant of the notch area in six defects. The newly formed tissues on the root were thick, collagenous, devoid of extrinsic fibres, and had an irregular surface contour. The presence of electron-dense, organic material in the collagenous matrix indicated at least partial mineralization. Embedded cells were numerous and the cells on the matrix surface were very large in size. Abundant rough endoplasmic reticulum and a prominent Golgi complex were evident. The presence of a split between the treated root surfaces and the newly formed tissue was a common observation, as was the presence of bacteria and host cells in the interfacial gap.
Following treatment with EMD, a bone-like tissue resembling cellular intrinsic fibre cementum may develop on the root surfaces, instead of AEFC. Furthermore, EMD may both induce de novo formation of a mineralized connective tissue on scaled root surfaces and stimulate matrix deposition on old native cementum. Interfacial bonding appeared to be weak after 6 weeks of healing.
釉基质衍生蛋白（EMD）被认为可触发无细胞外源性纤维牙骨质（AEFC）的形成，而其他报告表明EMD可能具有成骨潜力。本研究的目的是对应用EMD后牙根表面发育的组织进行特征描述。
选取12颗计划拔除的患牙周炎的人类牙齿，用EMD进行处理。2至6周后，拔除牙齿，脱矿并处理后嵌入丙烯酸树脂和环氧树脂中。通过光镜和透射电子显微镜分析新组织的形成。
在6个缺损处的切迹以及切迹区域以外的有刮治和无刮治的牙根表面均观察到牙根上有新组织形成。牙根上新形成的组织较厚，为胶原性，无外源性纤维，表面轮廓不规则。胶原基质中存在电子致密的有机物质表明至少有部分矿化。嵌入的细胞数量众多，基质表面的细胞体积非常大。可见丰富的粗面内质网和显著的高尔基体。在处理过的牙根表面与新形成的组织之间存在裂隙是常见的观察结果，界面间隙中存在细菌和宿主细胞也是如此。
用EMD处理后，牙根表面可能形成类似细胞内源性纤维牙骨质的骨样组织，而非AEFC。此外，EMD可能既诱导有刮治的牙根表面形成矿化结缔组织，又刺激旧的天然牙骨质上的基质沉积。愈合6周后，界面结合似乎较弱。
