Organo-chemical modification of titanium alloy and zirconia surfaces to achieve tight gingival adhesion (GingiSeal)

钛合金和氧化锆表面的有机化学改性以实现紧密的牙龈粘附（GingiSeal）

• 批准号: 418670251
• 负责人: Professor Dr.-Ing. Horst Fischer
• 金额: --
• 依托单位: Klinik für Zahnärztliche Prothetik und Biomaterialien, Zentrum für Implantologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/418670251?language=en
• 关键词: Organo; chemical; modification; titanium; alloy

Oral rehabilitation using dental implants provides several options for treating patients with tooth loss, thereby offering them better quality of life. In addition to the integration of the implant into the alveolar bone, the attachment of the surrounding soft tissue to the material surface of the implant's supraconstruction (abutment) plays an essential role. However, the peri-implant mucosa exhibits significant differences compared to that of a natural tooth. The natural ”seal” at the interface between mucosa and tooth, which is ensured by the so-called junctional epithelium, is missing in an implant-supported restoration. Thus, bacteria can easier penetrate into the interface and can subsequently provoke pathological processes at the interface between implant and alveolar bone. In the first phase of the research project GingiSeal, the abutment materials zirconia (Y-TZP) and the established titanium alloy (Ti6Al4V) were modified by self-assembled monolayers (SAM) and further functionalized with proteins of the extracellular matrix (ECM) with the help of a suitable cross linker. In-vitro experiments with human gingival fibroblasts have shown significantly enhanced cell adhesion, cell proliferation, cell spreading, and integrin expression on the organo-chemically modified surfaces compared to untreated surfaces. In addition to the mimicry of oral conditions in-vitro, which are tasks still to be completed within the first phase of the project, important further questions have arisen. In the second phase of the project, the exact adhesion mechanisms between the functionalized abutment surfaces and gingival epithelial cells is of importance. Furthermore, mass spectrometry will be used to determine how the crosslinker interacts with the proteins of the ECM. Furthermore, the bacterial DNA content on the differently modified surfaces will be determined via qPCR. In addition, a three-dimensional in vitro model of a gingival mucosa will be fabricated using bioprinting technology. A biofilm consisting of various bacteria strains is then applied to the interface between the modified/unmodified abutment material and the bioprinted mucosa substitute. The 3D model will be used to determine whether increased adhesion of the printed soft tissue to the modified abutment materials is impermeable to bacteria. For this purpose, live-dead staining will be performed, cytokine release from the printed gingival mucosa will be investigated by ELISA, and biofilm-induced cytotoxicity will be analyzed using a lactate dehydrogenase (LDH) assay. If the project progresses positively, the findings from the experiments with the bioprinted in vitro 3D model will form the foundation for a clinical pilot study envisaged after the two years.

使用种植体的口腔康复为治疗牙齿缺失的患者提供了几种选择，从而为他们提供了更好的生活质量。除了种植体与牙槽骨的结合外，周围软组织与种植体上部结构(基牙)材料表面的附着也起着至关重要的作用。然而，种植体周围的粘膜与天然牙相比表现出显著的差异。在种植体支持的修复中，由所谓的结合上皮所确保的粘膜和牙齿之间的自然“密封”是缺失的。因此，细菌可以更容易地渗透到界面，并随后在种植体和牙槽骨之间的界面处引发病理过程。在研究项目GingiSeal的第一阶段，利用自组装单分子膜(SAM)对基牙材料氧化锆(Y-TZP)和已建立的钛合金(Ti6Al4V)进行修饰，并在合适的交联剂的帮助下，进一步使用细胞外基质(ECM)的蛋白质进行功能化。体外实验表明，与未经处理的表面相比，有机化学修饰表面的细胞黏附、细胞增殖、细胞铺展和整合素表达显著增强。除了在体外模拟口腔条件外，这是该项目第一阶段仍需完成的任务，还出现了重要的进一步问题。在该项目的第二阶段，功能化基牙表面和牙龈上皮细胞之间的确切黏附机制是重要的。此外，将使用质谱学来确定交联剂如何与ECM的蛋白质相互作用。此外，不同改性表面上的细菌DNA含量将通过定量聚合酶链式反应进行测定。此外，还将使用生物打印技术制作牙龈粘膜的三维体外模型。然后，将由各种细菌菌株组成的生物膜应用于改性/未改性基牙材料与生物打印的粘膜替代物之间的界面。3D模型将被用来确定打印的软组织与改进的基牙材料之间的粘附性是否不会被细菌渗透。为此，将进行活体染色，将通过ELISA检测打印的牙龈粘膜中细胞因子的释放，并将使用乳酸脱氢酶(LDH)分析生物膜诱导的细胞毒性。如果该项目取得积极进展，使用生物打印的体外3D模型进行实验的结果将为两年后设想的临床先导研究奠定基础。