Development of dental implant with support of periodontal ligament

为了建立一种新型的牙周韧带(PDL)支持的种植体系统，我们研究了(1)不同体外条件下PDL细胞生物学特性的改变，(2)PDL细胞与羟基磷灰石(HA)种植体结合的合适载体，(3)PDL细胞结合HA种植体周围组织的组织学结构。研究表明：(1)PDL细胞在体外表现出其表型特征，生长分化受成纤维细胞生长因子、PDGF、EGF和机械应力的影响。(2)对于PDL细胞与HA种植体的结合和移植，(3)植入PDL细胞结合的HA种植体6个月后，种植体与骨之间已形成类PDL结缔组织，但未见真正的牙骨质沉积，未见胶原纤维植入。虽然目前尚不能观察到PDL细胞结合种植体周围真实的PDL支持，但这一结果为进一步改进PDL细胞与种植体结合的载体和结合方法提供了有用的信息。

To develop a new dental implant system with the support of periodontal ligament (PDL), we studied(1) modification of biological characteristics of PDL cells in different condition in vitro,(2) proper vehicles of PDL cells for conjugation to a hydroxyapatite (HA) implant, and(3) histological structure of peri-implant tissue around PDL cell conjugated HA implants.The studies showed(1) PDL cells showed their phenotypic characteristics in vitro and the growth and differentiation were modified with growth factors including FGF, PDGF and EGF and mechanical stress.(2) For PDL cell conjugation and transplantation with HA implants, membranous collagen was the most suitable vehicle.(3) At 6 months after the implantation of PDL cell conjugated HA implants, PDL-like connective tissue was formed between the implant and bone, but no true cementum deposition with inserting collagen fibers was observed.Although, in the present studies, we could not observe true PDL support around implants by PDL cell conjugation, the results give useful information for the further improvement of the vehicle and conjugation methods for PDL cell transplantation with implants.