干细胞和支架与牙髓再生及其血运重建

在牙髓再生中，获取干细胞的方法包括干细胞移植、细胞归巢和诱导出血。干细胞移植可产生异位的牙髓样组织，可控制移植细胞的数量并选择对牙髓再生潜在效能最佳的细胞亚种。细胞归巢是指利用信号分子招募宿主内源性干细胞至需治疗的牙体根管中增殖和分化，形成牙髓-牙本质样组织。诱导根尖出血进入根管为年轻恒牙牙髓再生的一个重要步骤。支架是细胞在合成组织时的支撑结构，可促进细胞黏附，为牙髓再生提供有利的环境。牙髓再生离不开血运重建或者血管再生，感染控制、根管预处理、冠方封闭等操作，可为牙髓再生包括其血运重建提供适宜的环境。总之，组织工程技术在牙髓领域的应用发展为牙髓再生带来了新的希望。

Stem cells and scaffolds in dental pulp regeneration and revascularization

Regenerative endodontics is defined as biologically based procedures designed to replace damaged structures, including dentin and root structures, as well as cells of the pulp–dentin complex. The methods of acquiring stem cells include stem-cell transplantation, cell homing, and induced bleeding. Stem-cell transplantation can yield ectopic dental pulp-like tissues, with the advantages of easily controlling the number of cells transplanted and selecting the optimal subpopulation of stem/progenitor cells. Meanwhile, cell homing is defined as the migration of endogenous host stem cells to the root canal of the offending teeth using signaling molecules. The process is also characterized by the subsequent proliferation and differentiation of the endogenous host stem cells into pulp–dentin-like tissues. Inducing pulp bleeding into the root canals of immature permanent teeth is an important step in regenerative endodontics. Scaffold refers to the structural support for the cells that synthesize tissues. This component promotes cell attachment and provides a specific environment conducive to pulp or dentin regeneration. Pulp regeneration cannot take place without revascularization or angiogenesis. Procedures such as infection control, pretreatment of root canals, and coronal sealing, provide a favorable environment for pulp regeneration, including pulp revascularization. The application and development of tissue engineering technology in endodontics bring new hope for dental pulp regeneration, despite the occurrence of numerous problems.