The periodontal ligament (PDL) is an essential fibrous tissue for tooth retention in the alveolar bone socket. PDL tissue further functions to cushion occlusal force, maintain alveolar bone height, allow orthodontic tooth movement, and connect tooth roots with bone. Severe periodontitis, deep caries, and trauma cause irreversible damage to this tissue, eventually leading to tooth loss through the destruction of tooth retention. Many patients suffer from these diseases worldwide, and its prevalence increases with age. To address this issue, regenerative medicine for damaged PDL tissue as well as the surrounding tissues has been extensively investigated regarding the potential and effectiveness of stem cells, scaffolds, and cytokines as well as their combined applications. In particular, PDL stem cells (PDLSCs) have been well studied. In this review, I discuss comprehensive studies on PDLSCs performed in vivo and contemporary reports focusing on the acquisition of large numbers of PDLSCs for therapeutic applications because of the very small number of PDLSCs available in vivo.

中文翻译：

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人牙周膜干细胞的大量采集。

牙周膜（PDL）是将牙齿保留在牙槽骨槽中的重要纤维组织。PDL组织还具有缓解咬合力，保持牙槽骨高度，允许正畸牙齿运动以及将牙根与骨骼连接的功能。严重的牙周炎，深龋和外伤会导致对该组织的不可逆转的损害，最终通过破坏牙齿固位而导致牙齿脱落。全球范围内，许多患者患有这些疾病，其患病率随着年龄的增长而增加。为了解决这个问题，针对干细胞，支架和细胞因子及其组合应用的潜力和有效性，已经广泛研究了受损PDL组织以及周围组织的再生药物。特别是，已经对PDL干细胞（PDLSC）进行了深入研究。在这篇评论中在体内和当代的报告中，由于体内可用的PDLSC数量很少，因此侧重于大量用于治疗应用的PDLSC的获取。