Papers by Author: Xiu Dong Yang

Abstract: As a natural biomaterial, collagen especially pepsin-solubilized collagen (type I) has been used widely in biomedical fields due to its excellent biocompatibility. In this preliminary study, we investigate the effect of some inorganic ions which are frequently utilized in the preparation of collagen on the morphology and crystallinity of fibrils. The scanning electron microscope and x-ray diffraction were applied to analyze the morphology and the crystallization of the reconstituted collagen fibrils, respectively. Although further studies are needed, these initial results indicate that by controlling the self-assembly conditions of collagen molecules, we may achieve the desired properties of fibrillar collagen products.

Abstract: Biomimetic coating on roughed titanium plates were prepared in this work by a cathode deposition method in calcium phosphate solution electrolyte. The coatings of plate-like apatite crystals were deposited on the titanium plates under a constant potential of 2.0V for 60 min at 37. The coating crystals were identified to be carbonate-containing apatite (bone-like apatite) by X-ray diffraction and scanning electronic microscopy. The cell proliferation and adhesion of L929 cells on the titanium metal plates with biomimetic coating and the titanium plates with roughed-only were tested. The results showed that biomimetic coating on titanium surface can enhance the materials bioactivity. The study indicated that cathode method is potential to prepare biomimetic coating on titanium implants with excellent bioactivity.

Abstract: Porous alpha- tricalcium phosphate (α-TCP) was implanted in rabbit and dog models to investigate its induction of calcium phosphate (Ca-P) formation. The morphology and structure of the formed Ca-Ps were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The results showed an animal-dependent behavior of in vivo Ca-P formation. There were flake-like octacalcium phosphate (OCP) precipitates in the rabbit but rod-like hydroxyapatite (HA) precipitates in the dog model. In addition, high-resolution TEM (HRTEM) image revealed that there was OCP structure in certain portions of the rod-like HA precipitates in the dog model. And the orientation relation of OCP/HA was deduced as OCP (010)//HA (0 10) and OCP (001)//HA (00 1) . This implied that the in vivo HA was formed via OCP precursor phase.

Abstract: Bonelike apatite coating on metal implants is an effective method to enhance bioactive properties of the metal surface. In the present study, the effectiveness of cathode deposition (CD) coating methods was investigated. And biomimetic deposition (BD) was also investigated as the parallel. The revised simulated body fluid (R-SBF) was chosen as an electrolyte and simulated body fluid. Both deposition methods could produce bonelike apatite coating on rough surfaces of the titanium. The uniformity of the CD coatings were better than the BD coatings’. And CD method was less sensitive to the condition of the titanium plate surfaces and much faster in the coating deposition. The spectra of FTIR showed that the characteristic peaks of CO3 2- apeared on the surface of ceramics, combined with spectra of XRD and SEM, it was concluded that a sertain thickness of bonelike apatite coating could be formed on the acided treatment (AT) titanium plate surfaces by CD method.

Abstract: The new-style injectable root canal filling material was prepared by hydroxyl apatite (HA), calcium hydroxide (Ca (OH) 2), iodoform (CHI3) and silicon oil. The material was injected into the isolate teeth to observe the sealing effect through marinating the isolate teeth in SBF and 1% methylblue solution. The practical effect of this material through clinical trials ten patients including fourteen teeth was also evaluated. After six months follow-up, patients have no any uncomfortable. This root canal filling material has good injectability, good biocompatibility, and is very convenient to manipulate. The relevant results suggest that it has good prospect of clinical application.