Research on Dental Pulp Stem Cells and Pulpal Healing Process

我们研究了牙齿损伤后牙体发育和牙髓愈合过程中的细胞动力学以及牙组织中的成体干细胞，得出以下结论：1。热休克蛋白（Heat-shock protein， HSP）-25蛋白被认为在牙形成过程中起着细胞增殖和终末细胞分化之间的开关作用。我们提出了一个新的概念，即产生各种牙子代的恒牙芽是在连续生长的牙齿的尖端形成的，并提出了一个新的术语“尖芽”来表示这种特殊的上皮结构。我们明确了牙髓对CrTmEr: YAG和CaAlAs激光照射的反应。GaAlAs激光可以通过影响成牙细胞的分泌活性来诱导第三牙本质的形成。然而，较高的能量可能导致牙髓发生不可逆转的变化，常常导致牙髓内骨样组织的形成。trap和ck阳性细胞的出现可能参与了牙髓骨组织形成的诱导。此外，缺乏适当的含氧培养基对成牙细胞系细胞的存活是决定性的，手术期间和/或手术后的咬合力使这些细胞的命运变得更糟。我们对舌下区域自体牙移植的实验研究支持了成牙细胞和成骨细胞谱系存在于牙髓中的观点。衰老的牙髓组织仍然具有防御能力，根据个体牙本质小管状态和/或成牙细胞过程的不同，可能发生各种反应。

We investigated the cell dynamics in the process of tooth development and pulpal healing after tooth injuries and the adult stem cells in the dental tissue, and reached the following conclusion.1. Heat-shock protein (HSP)-25 protein was suggested to act as a switch between cell proliferation and terminal cyto-differentiation during odontogenesis.2. We proposed a new concept that the eternal tooth bud producing various dental progeny is formed at the apical end of continuously growing teeth, and a new term "apical bud" for indicating this specialized epithelial structure.3. We clarified pulpal responses to CrTmEr : YAG and CaAlAs laser irradiation. The GaAlAs laser may induce the formation of tertiary dentin by influencing the secretory activity of odontoblasts. However, higher energies may cause irreversible changes to the pulp, often leading to the formation of an intra-pulpal bone-like tissue.4. The appearance of TRAP-and CK-positive cells may be involved in the induction of bone tissue formation in dental pulp. Furthermore, the lack of proper oxygenated medium is quite decisive for the survival of odontoblast-lineage cells and that the occlusal force during and/or after the operation make the fate of these cells worse.5. Our experimental study using autogenic tooth transplantation into the sublingual region supported the notion that odontoblast-and osteoblast-lineage cells reside in the dental pulp.6. Aged pulp tissue still, possesses the defense capacity, and a variety of reactions could occur depending on the difference in the status of dentinal tubules and/or odontoblast processes in individuals.