Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany; Department of Preventive, Restorative and Pediatric Dentistry, University of Bern, Bern, Switzerland.
Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany.
J Endod. 2017 Sep;43(9S):S7-S11. doi: 10.1016/j.joen.2017.06.003.
Signaling molecules play an essential role in tissue engineering because they regulate regenerative processes. Evidence exists from animal studies that single molecules such as members of the transforming growth factor beta superfamily and factors that induce the growth of blood vessels (vascular endothelial growth factor), nerves (brain-derived neurotrophic factor), or fibroblasts (fibroblast growth factor) may induce reparative dentin formation. Mainly the formation of atubular dentin (osteodentin) has been described after the application of single molecules or combinations of recombinant growth factors on healthy exposed pulps or in pulp regeneration. Generally, such preparations have not received regulatory approval on the market so far. Only the use of granulocyte colony-stimulating factors together with cell transplantation is presently tested clinically. Besides approaches with only 1 or few combined molecules, the exploitation of tissue-derived growth factors depicts a third promising way in dental pulp tissue engineering. Preparations such as platelet-rich plasma or platelet-rich fibrin provide a multitude of endogenous signaling molecules, and special regulatory approval for the market does not seem necessary. Furthermore, dentin is a perfect reservoir of signaling molecules that can be mobilized by treatment with demineralizing agents such as EDTA. This conditions the dentin surface and allows for contact differentiation of pulp stem cells into odontoblastlike cells, protects dentin from resorption, and enhances cell growth as well as attachment to dentin. By ultrasonic activation, signaling molecules can be further released from EDTA pretreated dentin into saline, thus avoiding cytotoxic EDTA in the final preparation. The use of dentin-derived growth factors offers a number of advantages because they are locally available and presumably are most fit to induce signaling processes in dental pulp. However, better characterization and standardization of the procedures are required.
信号分子在组织工程中起着至关重要的作用，因为它们调节再生过程。动物研究的证据表明，某些单一分子，如转化生长因子-β超家族的成员以及诱导血管（血管内皮生长因子）、神经（脑源性神经营养因子）或成纤维细胞（成纤维细胞生长因子）生长的因子，可能诱导修复性牙本质形成。主要描述了在健康暴露的牙髓或牙髓再生中应用单一分子或重组生长因子组合后形成的管状牙本质（骨样牙本质）。通常，到目前为止，这些制剂尚未在市场上获得监管部门的批准。目前仅在临床上测试了与细胞移植一起使用粒细胞集落刺激因子的方法。除了使用 1 种或少数几种组合分子的方法外，利用组织来源的生长因子描绘了牙髓组织工程的第三种有前途的方法。富含血小板的血浆或富含血小板的纤维蛋白等制剂提供了多种内源性信号分子，并且似乎不需要特殊的市场监管批准。此外，牙本质是信号分子的理想储存库，可以通过用 EDTA 等脱矿剂处理来动员这些信号分子。这可以调节牙本质表面，并允许牙髓干细胞接触分化为成牙本质细胞，保护牙本质免受吸收，并增强细胞生长以及与牙本质的附着。通过超声激活，可以将信号分子从 EDTA 预处理的牙本质进一步释放到盐水中，从而避免最终制剂中具有细胞毒性的 EDTA。牙本质衍生的生长因子的使用具有许多优点，因为它们是局部可用的，并且推测最适合诱导牙髓中的信号传递过程。但是，需要更好地对这些程序进行特征描述和标准化。
