Haiyong Ao, Chucheng Lin, Binen Nie, Shengbing Yang, Youtao Xie, Yizao Wan and Xuebin Zheng
Type I collagen and hyaluronic acid are both the main components of bone extracellular matrix, and play important roles in regulating a cell's behavior. In this study, the synergistic effects of type I collagen (Col) and hyaluronic acid (HA) on the biological properties of Col/HA-multilayer-modified titanium coatings were investigated. In vitro, the results of human mesenchymal stem cells culture indicated that Col/HA-multilayers-modified titanium coatings (TC-AA(C/H)6) could better improve a cell's adhesion, proliferation, and differentiation, compared with collagen-modified titanium coatings (TC-AAC) and hyaluronic acid-modified titanium coatings (TC-AAH). In vivo, the micro-CT images indicated that bone trabecula around TC-AA(C/H)6 were significantly more than with TC-AAC and TC-AAH. The fluorescence micrograph showed more active new bone formation around implants in TC-AA(C/H)6 group than in the TC-AAC and TC-AAH groups in the first month. Measurement of the bone-implant contact on the histological sections indicated there was significantly good osteointegration around TC-AA(C/H)6 implants than with the other two modified titanium coatings. All of these results demonstrated that there exists favorable synergistic effects of type I collagen and hyaluronic acid.