Papers by Author: Yi Kai Chen

Abstract: Biomaterials with good biocompatibility and anti-bacterial property were becoming attractive to researchers, so we used the chemical method to produce anti-bacterial vacuum plasma sprayed titanium coatings and studied In vitro bioactivity, cytotoxicity and blood compatibility of the anti-bacterial coatings in this paper. In order to evaluate the bioactivity of the treated titanium coatings, the coatings were immersed in simulated body fluid (SBF). The treated titanium coatings showed good bioactivity in this experiment. Two different methods were used to assess the cytocompatibility of the treated titanium coatings. One was extract test; the other was direct contact test. The results indicated that cells spread and adhered well on the coatings. The blood compatibility of the coatings was evaluated by haemolysis ratios. The hemolysis ratios of the coatings were below 2%, indicating of nonhemolysis for the coatings.

Abstract: Failure of dental implant is often caused by specific pathogenic bacteria. In this paper, antibacterial HA coating was prepared by vacuum plasma spraying with silver loaded zirconium phosphate containing HA as feedstock. The antibacterial activity against Aa，Fn and Pg was evaluated using a film covering method. MTT colorimetric assay was used to measure cytotoxic effect of the antibacterial HA coatings. Results show that the HA coatings displayed significant antibacterial activity against Aa，Fn, Pg and no cytotoxicity to L929 murine cell lines when the content of silver-loaded zirconium phosphate antimicrobial is between 5wt% to 10wt%. The sensitivity of the bacteria to the antibacterial HA coating is in sequence of Pg >Fn >Aa.

Abstract: In this paper, antibacterial silver-containing hydroxyapatite coating was prepared by vacuum plasma spraying method and osteoblasts were seeded onto the surface of the coating to evaluate its cytocompatibility. The results indicated that the cells proliferated well on the samples, and the proliferation rate on the silver-containing hydroxyapatite coating was a little bit higher than that on the silver-free hydroxyapatite coating. The contact angle of water drop on the coating was measured, and it was found that the contact angles of the silver-containing hydroxyapatite coatings were smaller than the hydroxyapatite coating. The improvement of hydrophilicity for the silver-containing hydroxyapatite coating could be beneficial to the cells proliferation on its surface. It can be concluded that the addition of silver in the hydroxyapatite coating endowed the coating with antibacterial property while maintaining its excellent cytocompatibility.

Abstract: Vacuum plasma sprayed (VPS) Ti coatings were deposited and their surface modification processes were performed by NaOH solution treatment and alkali-heat-calcification respectively. The simulated body fluid test indicated that apatite was formed on the surfaces of Ti coatings. A net-like structure was observed on the surfaces of Ti coatings treated by alkali-heat-calcification, whose bioactivity is much better than that treated by NaOH aqueous solution simply.