实现牙周组织形态与功能重建是牙再生的关键科学问题

Features and function reconstruction of periodontal tissue: a key point for tooth regeneration in vivo

组织工程与干细胞技术的发展为成功实现牙再生带来了希望,但牙周组织疾病却阻碍了再生牙体内应用的脚步。目前临床对牙周病的治疗并不能从根本上解决牙周功能重建的问题,主要原因可能在于对维持牙周稳态的重要干细胞-牙周膜间充质干细胞的认识不清。牙周膜间充质干细胞与骨髓间充质干细胞具有十分相似的特性,但更容易被炎症因子破坏正常的再生功能。慢性炎症是诱发牙周病最主要因素,如何应对炎症因子的破坏作用,是牙周膜间充质干细胞再生应用面临的难题。利用组织工程技术,牙周膜间充质干细胞聚合体可以成功在慢性炎症条件下实现牙周组织形态和功能的重建。另外考虑骨髓间充质干细胞对炎症因子的耐受性,在一定的条件刺激下,动员体内的骨髓间充质干细胞亦能实现牙周组织的修复重建。无论是上述外源性的,还是内源性的牙周重建再生方法的发展,对牙再生都具有十分重要的临床研究价值和科学研究意义。

It is possible to regenerate a tooth with new paradigm based on tissue engineering and regenerative medicine. However,a regenerative tooth can not survive in vivo or be applied in clinic,since periodontal diseases widely decrease the potential of regenerative teeth. Up to date,the treatment for periodontal diseases in clinic could not recover the regeneration capacity of periodontium successfully,probably because the function ofthe key cells-periodontal ligament stem cells（ PDLSCs） are not fully understood. The PDLSCs are similar as bone marrow-derived mesenchymal stem cells（ BMMSCs）,but more easily attracted by inflammation. Therefore,how to protect the cells against the inflammatory cytokines become a key problem for periodontal regeneration. On one hand,tissue engineering and cell aggregate system can realize the periodontium regeneration under inflammatory microenvironment successfully. On the other hand,BMMSCs canbe recruited into defect part of periodontium and take part in the regeneration process. Therefore,both endogenous and exogenous therapies for periodontium are important for not only clinical treatment but also scientific research.