Basic studies for the development of a new dental implant system with the support of periodontal ligament

为建立具有牙周膜支持的新型种植体系统奠定基础，我们建立了牙周膜细胞培养体系，并对其在不同培养条件下的形态和功能特性进行了研究。我们还在体外观察了PDL细胞对具有代表性的牙种植材料羟基磷灰石（HA）的行为。这些研究表明，培养的PDL细胞具有成骨水泥细胞/成骨细胞谱系细胞的细胞表型，这些细胞可以在HA上沉积骨质/骨样矿化组织。这些发现可以为HA- pdl细胞复合物植入骨的进一步研究提供科学依据，其中HA- pdl细胞复合物的骨强直程度低于单独植入的HA。虽然我们无法在本研究中使用的实验模型中证明PDL在HA上具有功能结构，但这一发现似乎值得支持将培养的PDL细胞应用于种植体表面可以实现种植体周围PDL支持的假设，也为开辟牙科种植学的新前景提供了基础。建议进一步研究PDL细胞的增殖和分化机制，改进培养的PDL细胞在种植材料上的应用方法。

To establish the fundamental background for the development of a new dental implant system with the support of periodontal ligament (PDL), we established culture systems for PDL cells and characterized their morphological and functional properties in different culture conditions. We also observed behaviors of PDL cells on hydroxy appatite (HA), that is one of the representative dental implant material, in vitro. Those studies showed that cultured PDL cells contain a cellular phenotype of the cementoblast/osteoblast lineage cells, and these cells could deposit cementum/bone-like mineralized tissue on HA.These findings could give scientific base for a further study on the implantation of a HA-PDL cells complex into the bone, where the HA-PDL cells complex showed less degree of ankylosis of bone than HA implanted alone. Although we could not demonstrated PDL with functional architectures on HA in the experimental models used in the present studies, the findings seemed to be worthy to support the hypothesis that the PDL-support around a dental implant can be realized by applying cultured PDL cells on a surface of implant, and also gave the fundamentals to open a new prospectivc in dental implantology. It was strongly suggested that further studies on the mechanism of proliferation and differentiation of PDL cells and the improvement of the method for application of cultured PDL cells on implant materials.