The induction of periodontal tissues by dentin-derived matrix

已知脱矿牙本质基质具有在植入部位诱导异位骨形成的高潜力，暗示牙本质基质中存在某些生物活性分子，其促进局部细胞分化成软骨形成和/或成骨细胞。目前的调查的目的是测试一个假设，即形成根牙本质的基质成分实际上可能有助于诱导牙周组织，主要是牙周间充质细胞分化成牙骨质细胞，在牙齿发育的过程中。HEBP是一种双膦酸盐，对生物矿化有很强的抑制作用，但不会对骨和牙齿细胞的基质形成功能产生明显的干扰。我们注意到，在HEBP感染的动物中， ...更多信息 牙本质沉积在牙根表面上，如果正在形成的牙根牙本质的矿化被抑制，并且因此未矿化的牙本质表面暴露于将来的牙周韧带，则已知在生理条件下仅形成无细胞牙本质。免疫组化结果显示，牙本质唾液酸蛋白是牙本质基质中的主要非胶原成分之一，当牙本质矿化受到抑制时，唾液酸蛋白可穿透牙本质的非矿化层并扩散到牙周膜中，提示蛋白质分子可通过牙本质层进行动态移位。在这些区域，釉原蛋白不能通过免疫组化定位，尽管事实上，牙本质基质含有低分子量的釉原蛋白，成牙本质细胞被报道瞬时表达釉原蛋白messages.In正常牙齿发育，上皮间充质界面之间的釉质和牙本质形成细胞层是串扰的网站，在那里各种信号分子是crosssing。我们的数据表明，非矿化的套牙本质层允许几乎自由通过的两个细胞层，分别产生非胶原牙本质基质蛋白和某些釉原蛋白mRNA剪接产物，这可能有助于诱导成牙骨质细胞和进一步的牙周组织的形成。在未来的研究中引入高灵敏度的分析方法，可能会允许可视化的候选分子的诱导成牙骨质细胞的从头形成的根牙本质表面的网站的独特定位。少

The demineralized dentin matrix has been known to have a high potential to induce ectopic bone formation at the site of implantation, implicating presence of certain bioactive molecules in the dentin matrix that facilitate differentiation of local cells into the chondrogenic and/or osteogenic cells. The aim of current investigation was to test a hypothesis that matrix components of the forming root dentin may in fact contribute to the induction of periodontal tissues, primarily on the differentiation of periodontal mesenchymal cells to cementoblasts, in the process of tooth development. The final goal of the study was to identify the bioactive molecule(s) and apply the data for the regeneration of periodontal tissues.HEBP is a type of bisphosphonate known to have high inhibitory effects on biological mineralization without causing notable interferences on the matrix forming functions of the cells of bones and teeth. We have noticed that, in the HEBP-affected animals, thick cellular cem … More entum is deposited on the root surface, where only acellular cernentum is known to form under physiological conditions, if mineralization of the forming root dentin is inhibited and hence the non-mineralized dentin surface is exposed to the future periodontal ligament. Immunohistochemical date revealed that dentin sialaprotein, one of major non-collagenous components of dentin matrix, penetrates through the non-mineralized layers of dentin and diffuses into the future periodontal ligament, implicating dynamic translocation of the proteinaceous molecules through dentin layers, if mineralization of dentin is inhibited. In such areas, amelogenin proteins could not be localized by immunohistochemistry, despite the fact that dentin matrix contains low molecular amelogenins and that odontoblasts are reported to transiently express amelogenin messages at least by PCR analyses.In normal tooth development, the epithelial-mesenchymal interface between the enamel and dentin forming cell layers is the site of crosstalk, where various signaling molecules are crisscrossing. Our data indicate that non-mineralized mantle dentin layers allow almost free passage of various molecules between the two cell layers that respectively generate non-collagenous dentin matrix proteins and certain amelogenin mRNA splice products, which might contribute to the induction of cementoblasts and further the formation of periodontal tissues. Introduction of highly sensitive analytical methods in future studies may allow visualization of distinct localization of candidate molecules for the induction of cementoblasts at the site of de novo formation of root dentin surface. Less