诱导性多能干细胞(iPSCs)在牙再生中的应用

干细胞能够自我更新并分化成各类组织细胞,在再生医学中具有很大的应用潜力。随着组织工程的快速发展,以胚胎干细胞和组织干细胞为基础的牙再生技术有待成为替代缺失牙的一种重要方法,然而免疫排斥和伦理的争议等问题为干细胞的临床应用带来很大的困难。由自体细胞产生的诱导性多能干细胞的发现将为牙齿再生带来革命性变化。本文就诱导性多能干细胞的研究背景及其在再生医学和牙再生领域的应用进展作一综述。     

炎症牙源性组织中的干细胞在牙周骨组织再生中的研究进展及应用前景

通过组织工程实现牙周骨组织再生是近年的研究热点。通常, 牙周组织工程的种子细胞来源于健康的牙源性组织, 但由于获得来源和拔牙适应证的限制, 健康牙源性干细胞的数量无法满足临床需求。炎症牙源性组织中的干细胞主要提取自炎症牙髓、根尖周及牙周组织, 具有较健康牙源性组织中的干细胞来源丰富、保留干细胞的部分基本特征等优点, 因而其有望应用于牙周骨组织再生领域。本文通过对炎症牙源性组织中的干细胞在牙周骨组织再生方面的应用现状及前景进行综述, 探讨该类细胞作为种子细胞的可行性, 以期为炎症牙源性组织中的干细胞研究及应用提供参考。     

成体干细胞及其在口腔颌面外科应用的研究进展

在干细胞深入研究和组织工程技术不断进步的基础上,将干细胞与组织工程结合应用于颌面部组织缺损的修复已成为国内外颌面外科领域研究的热点,而再生牙也初见端倪。本文重点综述成体干细胞及其在骨组织工程和牙再生领域应用研究的最新进展。     

牙源性干细胞的研究进展

牙源性干细胞(dental stem cells)具有优越的干细胞特性,可以从医疗废弃物(如正畸需要拔除的牙、智齿等)中获得,日益成为组织工程和再生医学研究的干细胞来源,这些干细胞的开发研究将为组织工程和再生医学的研究拓展更为广阔的空间,具有重要的转化研究价值。本文将对几种常见的牙源性干细胞的研究背景、研究现状等进行综述,并对未来应用前景进行展望。     

成体干细胞及其在口腔颌面外科应用的研究进展

在干细胞深入研究和组织工程技术不断进步的基础上。将干细胞与组织工程结合应用于颌面部组奴缺损的修复已成为固内外颌面外科领域研究的热点，而再生牙也初见端倪。本文重点综述成体干细胞及其在骨组织工程和牙再生领域应用研究的最新进展。     

牙再生的研究进展

牙再生是牙缺失修复的发展方向之一。研究者们应用组织工程和干细胞技术,多将种子细胞与支架材料结合,以定向诱导、分化种子细胞,使用体内及体外实验验证,进行全牙再生或部分牙再生的研究。本文对牙再生研究中应用的种子细胞和支架材料进行综述。     

牙髓干细胞的研究

牙髓干细胞是存在于牙髓组织中的一种成体干细胞，具有高度增殖、自我更新的能力和多向分化的潜能。牙髓干细胞的研究对牙组织工程和牙齿的再生将产生重要的意义。本文就牙髓干细胞的研究现状作一综述，并对其应用前景以及目前存在的问题进行讨论。     

牙髓干细胞生物学性能影响因素的研究进展

牙髓干细胞是最早体外成功分离培养的牙源性干细胞，具有较强的增殖能力及多向分化能力，是组织工程牙再生、骨再生研究中极具潜能的种子细胞。牙髓干细胞的生物学性能容易受到外界环境的影响，进而影响其在组织工程中的应用，因此选择一个适合牙髓干细胞培养的微环境是非常重要的。本文基于现有文献，从细胞因子、条件培养液、支架材料、物理因素等对牙髓干细胞生物学性能的影响展开综述。     

再生牙髓病学--牙髓再生的新方向

再生牙髓病学主要采用引导组织再生原理,通过组织工程学技术促进根管内牙髓再生,是牙髓再生治疗的新方向和新选择。在再生牙髓病学中,牙源性干细胞、生物支架以及生长因子是3个关键因素,逐渐成为学者们研究的热点。     

牙源性干细胞及牙髓再生的研究进展

牙髓组织中含有细胞、血管、神经和纤维等,是一个复杂的3D结构系统。随着干细胞生物学和组织工程学的相互结合和促进,牙髓再生逐渐成为可能。牙体组织中分离出的多种干细胞,如牙髓干细胞、脱落乳牙牙髓干细胞、根尖牙乳头干细胞、牙囊干细胞等,都具有再生牙髓的潜能。文章就牙源性干细胞及以牙源性干细胞为基础的牙髓再生的研究进展做一综述。     

Stem cell‐based tooth and periodontal regeneration

Currently regeneration of tooth and periodontal damage still remains great challenge. Stem cell‐based tissue engineering raised novel therapeutic strategies for tooth and periodontal repair. Stem cells for tooth and periodontal regeneration include dental pulp stem cells (DPSCs), periodontal ligament stem cells (PDLSCs), stem cells from the dental apical papilla (SCAPs), and stem cells from human exfoliated deciduous teeth (SHEDs), dental follicle stem cells (DFSCs), dental epithelial stem cells (DESCs), bone marrow mesenchymal stem cells (BMMSCs), adipose‐derived stem cells (ADSCs), embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). To date, substantial advances have been made in stem cell‐based tooth and periodontal regeneration, including dentin–pulp, whole tooth, bioroot and periodontal regeneration. Translational investigations have been performed such as dental stem cell banking and clinical trials. In this review, we present strategies for stem cell‐based tissue engineering for tooth and periodontal repair, and the translational studies.     

牙齿再生——梦想与现实

牙齿及牙列缺失在临床上很常见，目前的修复方法均为非生物性的，尚不能满足人们的要求。实现真牙再生一直是一个梦想。牙齿再生分为全牙再生和部分牙齿再生，前者目前尚存在相当大的困难，但后者已有可喜进展，已在小鼠及大型动物小型猪上成功再生出生物牙根，有望成为全牙再生成功前良好的过渡。研究表明骨髓中部分细胞在一定条件下可以直接分化为成釉上皮样细胞及成牙本质细胞，有望成为牙齿再生的间充质来源的种子细胞。     

Regenerative endodontics as a tissue engineering approach: Past,current and future

With the reported startling statistics of high incidence of tooth decay and tooth loss, the current interest is focused on the development of alternate dental tissue replacement therapies. This has led to the application of dental tissue engineering as a clinically relevant method for the regeneration of dental tissues and generation of bioengineered whole tooth. Although, tissue engineering approach requires the three main key elements of stem cells, scaffold and morphogens, a conductive environment (fourth element) is equally important for successful engineering of any tissue and/or organ. The applications of this science has evolved continuously in dentistry, beginning from the application of Ca(OH)₂ in vital pulp therapy to the development of a fully functional bioengineered tooth (mice). Thus, with advances in basic research, recent reports and studies have shown successful application of tissue engineering in the field of dentistry. However, certain practical obstacles are yet to be overcome before dental tissue regeneration can be applied as evidence‐based approach in clinics. The article highlights on the past achievements, current developments and future prospects of tissue engineering and regenerative therapy in the field of endodontics and bioengineered teeth (bioteeth).     

组织工程化牙齿研究展望

本文通过综述牙齿发育学家、牙髓生物学家的态度，对组织工程化牙齿研究的前景进行了展望；并且对组织工程化牙齿研究现状以及发育学和干细胞生物学与组织工程化牙齿研究之间的联系进行了回顾。     

Mesenchymal stem cells in the dental tissues: perspectives for tissue regeneration

In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that range from Alzheimer's disease to cardiac ischemia and regenerative medicine, like bone or tooth loss. Based on their ability to rescue and/or repair injured tissue and partially restore organ function, multiple types of stem/progenitor cells have been speculated. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental tissues are considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that these stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. In dentistry, stem cell biology and tissue engineering are of great interest since may provide an innovative for generation of clinical material and/or tissue regeneration. Mesenchymal stem cells were demonstrated in dental tissues, including dental pulp, periodontal ligament, dental papilla, and dental follicle. These stem cells can be isolated and grown under defined tissue culture conditions, and are potential cells for use in tissue engineering, including, dental tissue, nerves and bone regeneration. More recently, another source of stem cell has been successfully generated from human somatic cells into a pluripotent stage, the induced pluripotent stem cells (iPS cells), allowing creation of patient- and disease-specific stem cells. Collectively, the multipotency, high proliferation rates, and accessibility make the dental stem cell an attractive source of mesenchymal stem cells for tissue regeneration. This review describes new findings in the field of dental stem cell research and on their potential use in the tissue regeneration.     

牙周膜干细胞的研究进展

牙周病是一种由菌斑微生物引起的慢性感染性疾病,可引起牙周支持组织的破坏和丧失,最终导致牙齿松动脱落。牙周病治疗的最终目标是修复和重建受损的牙周支持组织。从牙周膜中分离获取的间充质干细胞具有成体干细胞的特性及多重分化潜能,可以分化为骨组织和牙周支持组织等多种类型的组织,这对牙周组织修复再生和牙周组织工程具有重大意义,因而备受关注。本文就牙周膜干细胞、牙周膜干细胞的生物学特性、牙周膜干细胞的影响因素及其调控机制等研究进展作一综述。     

Pulp tissue from primary teeth: new source of stem cells

SHED (stem cells from human exfoliated deciduous teeth) represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin.     

Dental follicle stem cells and tissue engineering

Adult stem cells are multipotent and can be induced experimentally to differentiate into various cell lineages. Such cells are therefore a key part of achieving the promise of tissue regeneration. The most studied stem cells are those of the hematopoietic and mesenchymal lineages. Recently, mesenchymal stem cells were demonstrated in dental tissues, including dental pulp, periodontal ligament, and dental follicle. The dental follicle is a loose connective tissue that surrounds the developing tooth. Dental follicle stem cells could therefore be a cell source for mesenchymal stem cells. Indeed, dental follicle is present in impacted teeth, which are commonly extracted and disposed of as medical waste in dental practice. Dental follicle stem cells can be isolated and grown under defined tissue culture conditions, and recent characterization of these stem cells has increased their potential for use in tissue engineering applications, including periodontal and bone regeneration. This review describes current knowledge and recent developments in dental follicle stem cells and their application.