Promoting the Bone Tissue Response to Titanium Dental Implant through Formation of Three-Dimensional Surface Structure of Imitation of Extracellular Matrix (Ecm) Characters(2/3)

Sand-blasting/acid-etching (SLA) process is a gold-standard for titanium (Ti) dental implant surface treatment. However, the Ti surface after SLA treatment is still bioinert. Thus, it is a future trend to develop dental implant surface being able to initiatively induce the surrounding bone tissue growth. The purpose of this three-year project is to promote the bone tissue response to titanium dental implant surface through the formation of three-dimensional (3D) surface structure of imitation of extracellular matrix (ECM) characters. We will create a hydrophilic ECM-like 3D fibrous structure on Ti surface through sand-blasting/acid-etching/alkaline-etching surface treatments. Followed by immobilizing type I collagen, the most abundant protein in ECM, on the hydrophilic ECM-like 3D fibrous surface to promote bone tissue repair and angiogenesis as well as to alleviate inflammation. In the first year, sand-blasting will firstly be performed on Ti surface, followed by acid-etching in different mixed acids. Sequentially, alkali-etching will be additionally performed on the sand-blasted/acid-etched Ti surfaces at room temperature and 60°C, respectively. We expect to produce a hydrophilic ECM-like 3D fibrous surface on Ti surface. Various surface characteristics and in vitro initial biological responses, including cytotoxicity, proteins adsorption, and bioactivity, will be analyzed. In the second year, according to the results obtained in the first year, the optimal surface treatment condition, i.e., condition for simultaneously obtaining both the good initial biological responses and the hydrophilic ECM-like 3D fibrous structure, will be used for modifying the test specimens, followed by the type I collagen immobilization. Two different concentrations of the natural cross-linker, procyanidin, will be selected to immobilize the collagen onto the Ti surfaces treated with the selected condition optimally obtained in the first year. After collagen immobilization, various surface characteristics, cytotoxicity, and (hBMSCs) responses, will be analyzed. In the third year, according to the results of the second year, the best condition to immobilize collagen (with and without cross-linker procyanidin) will be selected as the surface treatment for the test Ti specimens. Then, various responses of cells, including hBMSCs, human umbilical vein epidermal cells (HUVEC), and monocyte/macrophage, will be analyzed in detail. This project is expected to promote the bone tissue response to Ti dental implant surface through the formation of 3D hydrophilic surface structure of imitation of ECM characters. The result is expected to help develop a new generation of Ti dental implant surface treatment that is globally competitive in the market.