Study On The Cyto-biocompatibility Of Two Neotype Implant Titanium Alloys And The Alloy With Surface Treatments

Pure titanium and titanium alloy possess great mechanical properties, making them suitable for load-bearing applications and implant. Titanium and its alloys are already widely used in orthopedics and dentistry because of their good biocompatibility. However, high stiffness of the meatals often leads to stress-shielding from residual bone, which may result in detrimental resorption bone remodeling, and consequently to a poor fixation of the implant. Recent developments in metallic implant designs therefore focus on adapting the mechanical properties of metals to those of biological systems. Our group has recently developed two new-type titanium alloys and surface modifications of the titanium alloy which purpose with satisfied good biomechanics performance and biocompatibility.[1], supported by the 863 Project (2002AA306070). Two types of new medical titanium alloys- Ti-5Zr-5Mo-15Nb (TLE) and Ti-5Zr-3Sn-5Mo- 15Nb (TLM) were developed, and surface modification to TLE using microarc oxidation (M), in which surface titanium oxide layer was developed; plasma liquid phase nitridation technique (N), in which surface layer attrition-resistant titanium nitride existed; sandblasting (P) and sandblasted and acid-etched (SLA). The neotype titanium and different surface modifications on cell responses are not known. Biocompatibility evaluation must be carried out for Neotype biomaterial before clinical application.The purpose of this study was to evaluate a series of osteoblasts reacting behavior to neotype titanium alloy and the alloy with surface modifications. The cell behavior was evaluated including osteoblast morphology, proliferation, differentiation, and expression of ALP. The osteoblasts were obtain from 6 neonate rats calvarial bone and coculture with the neotype titanium alloy and surface modifications in vitro. The main conclusions are following:1. The neotype titanium alloys are with well cyto biocompatibility due to an effect that enhancing osteoblasts proliferation and the cell flatten and elongated as well as standard tissue plastic plate.2. The titanium alloy with the microarc oxidation coating, the plasma liquid phase nitridation coating, and coarse processing show a better cell biocompatibility, which included cell attachment, proliferation, morphologic and ALP expression. Moreover, owing to pore structure on the surface of the microarc oxidation coating and the coarse surface, their treated surfaces are in favour of cell biologic behavior.