Materials Transactions, Vol.50 No.05 (2009) pp.1190-1195
© 2009 The Japan Institute of Metals
Formation and Osteoconductivity of Hydroxyapatite/Collagen Composite Films Using a Thermal Substrate Method in Aqueous Solutions
1Department of Materials Science & Engineering, Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
2EcoTopia Science Institute, Nagoya University, Nagoya 464-8603, Japan
3Hamri Co., Ltd., Tokyo 110-0005, Japan
We have studied the formation and carried out an in vivo evaluation of hydroxyapatite (HAp)/collagen and HAp/denatured collagen (gelatin) composite coatings on titanium substrates using a thermal substrate method. The coatings were formed on commercial pure titanium rods (diameter = 2 mm, length = 5 mm) and plates (thickness = 0.3 mm) using a thermal substrate method in aqueous solutions that contained 0.3 mM Ca(H2PO4)2, 0.7 mM CaCl2, and a concentration of acid-soluble collagen (Type I) of ∼432 mg dm-3. The coating experiments were conducted at 40–140°C and pH=8 for periods of 15 or 30 min. The coating temperature and collagen content in the solution influenced the surface morphology and collagen (or gelatin) content in the films. A coated rod was implanted in a 10-week-old male rat's tibia with a non-coated titanium rod being used as a control. The constructs were retrieved after a period of 14 d postimplantation and examined for new bone formation and for tissue response in the cancellous and cortical bone parts, respectively. HAp/gelatin composite films coated at > 60°C showed a slight improvement in osteoconductivity in the cortical bone. In contrast, there was no improvement in the cancellous bone, compared with HAp, which had no gelatin. However, the HAp/collagen composites showed a high osteoconductivity in the cortical bone region, and this increased with increasing collagen content in the films. There was the same tendency in the cancellous bone part. However, too higher a collagen content (40 mass%) in the films gave rise to an obvious negative osteoconductive effect.
(Received 2008/12/11; Accepted 2009/2/26; Published 2009/4/15)
Keywords: hydroxyapatite, collagen, gelatin, hydro-coating, surface morphology, thermal substrate method, in vivo
Table of Contents
- L. L. Hench and J. Wilson: An Introduction to Bioceramics, (World Scientific, Singapore, 1993).
- H. Aoki: Marvelous Biomaterial, Apatite, (Ishiyaku Publishers, Inc., 1999) p.19 (in Japanese).
- M. C. Chang, T. Ikoma, M. Kikuchi and J. Tanaka: J. Mater. Sci. Lett. 20 (2001) 1199–1201.
- R. Z. Wang, F. Z. Cui, H. B. Lu, H. B. Wen, C. L. Ma and H. D. Li: J. Mater. Sci. Lett. 14 (1995) 490–492.
- M. C. Chang, C. Ko and W. Douglas: Biomater. 24 (2003) 2853–2862.
- T. Ishii, M. Koishi and T. Tsunoda: Nure-gijutsu handbook, (Techno-system, Tokyo, 2001), Chap.16 (in Japanese).
- T. Okada and Y. Ikada: J. Biomater. Sci. Polymer Edn. 7 (1995) 171–180.
- K. Kuroda, R. Ichino, M. Okido and O. Takai: J. Biomed. Mater. Res. 59 (2002) 390–397.
- K. Kuroda, S. Nakamoto, R. Ichino, M. Okido and R. M. Pilliar: Mater. Trans. 46 (2005) 1633–1635.
- K. Kuroda, R. Ichino, M. Okido and O. Takai: J. Biomed. Mater. Res. 61 (2002) 354–359.
- K. Kuroda, Y. Miyashita, R. Ichino, M. Okido and O. Takai: Mater. Trans. 43 (2002) 3015–3019.
- K. Kuroda, S. Nakamoto, Y. Miyashita, R. Ichino and M. Okido: Mater. Trans. 47 (2006) 1391–1394.
- K. Kuroda, S. Nakamoto, Y. Miyashita, R. Ichino and M. Okido: J. Jpn. Inst. Metals 71 (2007) 342–345.
- K. Kuroda, M. Moriyama, R. Ichino, M. Okido and A. Seki: Mater. Trans. 49 (2008) 1434–1440.
- M. S. Tung and T. J. O'Farrell: Coll. Surf. A 110 (1996) 191–198.
- Y. Fang, D. K. Agarwal, D. M. Roy, R. Roy and P. W. Brown: J. Mater. Res. 7 (1992) 2294–2298.
- K. Koyama and Y. Hashimoto: J. Jpn. Inst. of Metals 51 (1987) 678–685.
- T. Matsumoto, K. Tamine, R. Kagawa, Y. Hamada, M. Okazaki and J. Takahashi: J. Ceram. Soc. Jpn. 114 (2006) 760–762.
© 2009 The Japan Institute of Metals
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