Development of successful intentional replantation

意向性再植是一种保守治疗方法，主要应用于根尖周炎、牙根折裂等顽固性疾病的治疗。目前，除了在拔牙过程中尽量减少对牙周膜组织的损伤外，尚无促进再植后牙周愈合的药物报道。在此背景下，我们的目的是澄清血管紧张素II（AngII），血管紧张素原的代谢产物，对牙周再植后愈合的影响。为此，我们决定建立大鼠牙周再植实验模型，研究AngII对牙周愈合的影响，并检测AngII肽对未分化人牙周膜细胞的影响。结果，AngII处理增加了大鼠模型PDL组织中的血管生成，并且进一步减少了异位骨形成。我们发现AngII肽处理的PDL细胞增加了肌腱/韧带相关分子和血小板反应蛋白2（THBS 2）的基因表达，THBS 2是牙囊的标志物之一。这些结果表明AngII治疗在意向性再植、减少关节强直和促进牙周愈合方面的有效性。

Intentional replantation is one of conservative dental treatments, that is applied for refractory periapical periodontitis and fractured tooth root subjected to oxtraoral adhesive treatment. No medicines to promote the periodontal healing after replantation have been reported except to minimize the damage to periodontal ligament (PDL) tissue during extraction. In this context, we aimed to clarify the effects of Angiotensin II (AngII), a metabolite of Angiotensinogen, on the periodontal healing after replantation. For this purpose we decided to develop the replantationexperimental model rats, and investigated the effects of AngII on periodontal healing and in addition examined the AngII peptides affected undifferentiated human PDL cells. In consequence, the AngII treatment increased angiogenesis in PDL tissue in rat model, and furthermore reduced the ectopic bone formation in it. We found that an AngII peptide-treated PDL cells increased the gene expression of tendon/ligament-related molecules and Thrombospondin 2 (THBS2), one of the markers of the dental follicle. These results suggested the efficacy of AngII treatment in intentional replantation,reducing ankylosis and promoting periodontal healing.